CN112048710A - LED epitaxial growth method for reducing blue shift quantity of LED light-emitting wavelength - Google Patents

Abstract

Translated fromChinese

本申请公开了一种减少LED发光波长蓝移量的LED外延生长方法，依次包括：处理衬底、生长低温GaN缓冲层、生长不掺杂GaN层、生长掺杂Si的N型GaN层、生长多量子阱发光层、生长AlGaN电子阻挡层、生长掺杂Mg的P型GaN层，降温冷却，其中生长多量子阱发光层依次包括生长InGaN阱层、掺Si预处理、生长In渐变减少In_XGa_1‑X层、生长In渐变增加In_yN_1‑y层、生长In恒定In_zAl_1‑z层、Mg扩散处理、生长GaN垒层和InGaN：Mg/Si保护层的步骤。本发明方法解决现有LED外延生长中存在的LED发光波长蓝移量较大的问题，同时提高LED的发光效率，降低工作电压，增强抗静电能力。

The present application discloses an LED epitaxial growth method for reducing the blue shift of the LED emission wavelength, which sequentially includes: processing a substrate, growing a low-temperature GaN buffer layer, growing an undoped GaN layer, growing a Si-doped N-type GaN layer, growing Multi-quantum well light-emitting layer, growing AlGaN electron blocking layer, growing Mg-doped P-type GaN layer, cooling and cooling, wherein growing the multi-quantum well light-emitting layer sequentially includes growing an InGaN well layer, doping Si pretreatment, growing In gradually reducing In_X Steps of Ga_1-X layer, growing In graded In_y Ni_1-y layer, growing In constant In_z Al_1-z layer, Mg diffusion treatment, growing GaN barrier layer and InGaN:Mg/Si protective layer. The method of the invention solves the problem of large blue-shift of the LED light-emitting wavelength existing in the existing LED epitaxial growth, and at the same time improves the light-emitting efficiency of the LED, reduces the working voltage and enhances the antistatic ability.

Description

Translated fromChinese

一种减少LED发光波长蓝移量的LED外延生长方法A LED epitaxial growth method for reducing the blue shift of LED emission wavelength

技术领域technical field

本发明属于LED技术领域，具体涉及一种减少LED发光波长蓝移量的外延生长方法。The invention belongs to the technical field of LEDs, and in particular relates to an epitaxial growth method for reducing the blue-shift of LED emission wavelengths.

背景技术Background technique

发光二极管(Light-Emitting Diode，LED)是一种将电能转化为光能的半导体电子器件。LED作为一种高效、环保、绿色新型固态照明光源，已经被广泛应用于交通信号灯、汽车灯、室内外照明、显示屏和小间距显示屏。Light-Emitting Diode (LED) is a semiconductor electronic device that converts electrical energy into light energy. As an efficient, environmentally friendly and green new solid-state lighting source, LED has been widely used in traffic lights, car lights, indoor and outdoor lighting, display screens and small-pitch displays.

小间距显示屏采用像素级的点控技术，实现对显示屏像素单位的亮度、色彩的还原性和统一性的状态管控。小间距显示屏要求在注入不同大小电流改变发光强度的过程中，发光波长的变化幅度较小。The small-pitch display adopts pixel-level point control technology to realize the state control of the brightness, color restoration and uniformity of the display pixel unit. The small-pitch display requires a small change in the luminous wavelength during the process of injecting currents of different sizes to change the luminous intensity.

目前传统的LED外延InGaN/GaN多量子阱发光层生长方法中，InGaN和GaN的晶格结构为纤锌矿结构，这种结构缺少变换对称性，在材料内部容易产生自发极化，同时InGaN阱层和GaN垒层的晶格常数不匹配产生的应力导致出现压电极化现象。自发极化和压电极化的共同作用致使量子阱内部存在很大的电场，导致量子阱的能带倾斜。随着注入电流的增大，量子阱的自由载流子增加，量子阱中基态升高，从而使LED的发光波长向短波方向移动，即发生蓝移。当小间距显示屏中注入不同大小电流改变发光强度时，LED发光波长的蓝移量会出现较大差别，无法满足小间距显示屏的应用需要。In the current traditional LED epitaxial InGaN/GaN multi-quantum well light-emitting layer growth method, the lattice structure of InGaN and GaN is a wurtzite structure. This structure lacks transformation symmetry and is prone to spontaneous polarization inside the material. At the same time, the InGaN well Piezoelectric polarization occurs due to stress caused by the mismatch of lattice constants between the layers and the GaN barrier layer. The combined action of spontaneous polarization and piezoelectric polarization results in a large electric field inside the quantum well, which leads to the inclination of the energy band of the quantum well. With the increase of the injection current, the free carriers of the quantum well increase, and the ground state in the quantum well increases, so that the light-emitting wavelength of the LED moves to the short-wave direction, that is, a blue-shift occurs. When different sizes of currents are injected into the small-pitch display to change the luminous intensity, the blue-shift of the LED light-emitting wavelength will vary greatly, which cannot meet the application needs of the small-pitch display.

因此，提供一种减少LED发光波长蓝移量的外延生长方法，解决现有LED外延生长中存在的LED发光波长蓝移量较大的问题，以满足小间距显示屏的应用需要，是本技术领域亟待解决的技术问题。Therefore, to provide an epitaxial growth method that reduces the blue shift of the LED light-emitting wavelength, solves the problem of the large blue-shift of the LED light-emitting wavelength in the existing LED epitaxial growth, and meets the application needs of small-pitch display screens. technical problems to be solved in the field.

发明内容SUMMARY OF THE INVENTION

本发明通过采用新的多量子阱发光层生长方法来解决现有LED外延生长中存在的LED发光波长蓝移量较大的问题，同时提高LED的发光效率，降低工作电压，增强抗静电能力。The present invention solves the problem of large blue-shift of the LED light-emitting wavelength existing in the existing LED epitaxial growth by adopting a new multi-quantum well light-emitting layer growth method, and at the same time improves the light-emitting efficiency of the LED, reduces the working voltage, and enhances the antistatic ability.

本发明的减少LED发光波长蓝移量的外延生长方法，依次包括：处理衬底、生长低温GaN缓冲层、生长不掺杂GaN层、生长掺杂Si的N型GaN层、生长多量子阱发光层、生长AlGaN电子阻挡层、生长掺杂Mg的P型GaN层，降温冷却；所述生长多量子阱发光层依次包括：生长InGaN阱层、掺Si预处理、生长In渐变减少In_XGa_1-X层、生长In渐变增加In_yN_1-y层、生长In恒定In_zAl_1-z层、Mg扩散处理、生长GaN垒层和InGaN：Mg/Si保护层，具体为：The epitaxial growth method for reducing the blue-shift of the LED light-emitting wavelength of the present invention sequentially includes: processing the substrate, growing a low-temperature GaN buffer layer, growing an undoped GaN layer, growing a Si-doped N-type GaN layer, growing multiple quantum wells for light emission layer, growing an AlGaN electron blocking layer, growing a Mg-doped P-type GaN layer, cooling down and cooling; the growing multiple quantum well light-emitting layer sequentially includes: growing an InGaN well layer, doping Si pretreatment, growing In gradient reduction In_X Ga_{1 -X} layer, growth of In graded increase InyN1_-ylayer , growth of In constant InzAl1_-zlayer , Mg diffusion treatment, growth of GaN barrier layer and InGaN:Mg/Si protective layer, specifically:

A、控制反应腔压力280-350mbar，控制反应腔温度800-850℃，通入流量为50000-70000sccm的NH₃、20-40sccm的TMGa、10000-15000sccm的TMIn，生长厚度为3nm的InGaN阱层；A. Control the pressure of the reaction chamber to 280-350 mbar, control the temperature of the reaction chamber to 800-850 ℃, pass in NH₃ with a flow rate of 50,000-70,000 sccm, TMGa with a flow rate of 20-40 sccm, and TMIn with a thickness of 10,000-15,000 sccm, and grow an InGaN well layer with a thickness of 3 nm. ;

B、保持反应腔的温度和压力不变，通入NH₃、SiH₄、TMIn，关闭TMGa，做5-10秒掺Si预处理；B. Keep the temperature and pressure of the reaction chamber unchanged, pass in NH₃ , SiH₄ , TMIn, turn off TMGa, and do Si doping pretreatment for 5-10 seconds;

C、控制反应腔的温度和压力不变，关闭SiH₄，通入TMGa和TMIn，生长3-7nm的In_XGa_1-X层，其中X的范围为0.1-0.15，生长过程中控制In的掺杂浓度由1E21 atom/cm³均匀渐变减少至1E20 atom/cm³；C. Control the temperature and pressure of the reaction chamber to remain unchanged, turn off SiH₄ , pass in TMGa and TMIn, and grow a 3-7nm In_X Ga_1-X layer, where X ranges from 0.1 to 0.15. During the growth process, control the amount of In The doping concentration is uniformly reduced from 1E21 atom/cm³ to 1E20 atom/cm³ ;

D、反应腔的压力保持不变，将反应腔温度升高至900-950℃，关闭TMGa，通入NH₃和TMIn，生长10-15nm的In_yN_1-y层，其中y的范围为0.2-0.25，生长过程中控制In的掺杂浓度由1E20 atom/cm³均匀渐变增加至1E21 atom/cm³；D. The pressure of the reaction chamber remains unchanged, the temperature of the reaction chamber is increased to 900-950 ° C, the TMGa is turned off, NH₃ and TMIn are passed in, and a 10-15 nm In_y N_1-y layer is grown, where the range of y is 0.2-0.25, during the growth process, the doping concentration of In is controlled to increase uniformly and gradually from 1E20 atom/cm³ to 1E21 atom/cm³ ;

E、升温至1000～1050℃，反应腔压力维持在200-300mbar，关闭TMIn，通入NH₃和TMAl，生长5-10nm的In_zAl_1-z层，其中Z的范围为0.2-0.3，生长过程中控制In的掺杂浓度恒定为2E20 atom/cm³；E. The temperature is raised to 1000-1050 °C, the pressure of the reaction chamber is maintained at 200-300 mbar, TMIn is turned off, NH₃ and TMAl are passed in, and a 5-10 nm In_z Al_1-z layer is grown, wherein the range of Z is 0.2-0.3, During the growth process, the doping concentration of In is controlled to be constant 2E20 atom/cm³ ;

F、控制反应腔的温度和压力不变，停止通入TMAl，保持NH₃气的通入，并通入Cp₂Mg进行Mg扩散处理，处理过程中控制Mg的掺杂浓度由2E21 atom/cm³均匀的变化到3E22atom/cm³，Mg扩散处理时间为15-20s；F. Control the temperature and pressure of the reaction chamber to remain unchanged, stop the introduction of TMAl, keep the introduction of NH₃ gas, and introduce Cp₂ Mg for Mg diffusion treatment. During the treatment process, control the doping concentration of Mg from 2E21 atom/cm³ uniform change to 3E22atom/cm³ , the Mg diffusion treatment time is 15-20s;

G、保持反应腔压力不变，降低反应腔温度至700-750℃，通入流量为30000-40000sccm的NH₃、20-60sccm的TMGa及100-130L/min的N₂，生长10nm的GaN垒层；G. Keep the pressure of the reaction chamber unchanged, reduce the temperature of the reaction chamber to 700-750 ℃, pass in NH₃ with a flow rate of 30000-40000 sccm, TMGa with a flow rate of 20-60 sccm and N₂ with a flow rate of 100-130 L/min, and grow a 10 nm GaN barrier Floor;

H、保持反应腔压力不变，升高反应腔温度至780-820℃，通入流量为36000-40000sccm的NH₃、80-100sccm的TMGa、4000-5000sccm的TMIn以及Cp₂Mg和SiH₄，生长厚度为2.5-3.5nm的InGaN：Mg/Si保护层，其中，Mg和Si的掺杂比例为1:1.5；H. Keep the pressure of the reaction chamber unchanged, raise the temperature of the reaction chamber to 780-820 ℃, and feed NH₃ with a flow rate of 36000-40000 sccm, TMGa with a flow rate of 80-100 sccm, TMIn with a flow rate of 4000-5000 sccm, Cp₂ Mg and SiH₄ , growing an InGaN:Mg/Si protective layer with a thickness of 2.5-3.5nm, wherein the doping ratio of Mg and Si is 1:1.5;

重复上述步骤A-H，周期性依次进行生长InGaN阱层、掺Si预处理、生长In渐变减少In_XGa_1-X层、生长In渐变增加In_yN_1-y层、生长In恒定In_zAl_1-z层、Mg扩散处理、生长GaN垒层和InGaN：Mg/Si保护层，周期数为3-10个。Repeat the above steps AH, and periodically perform the growth of the InGaN well layer, the pretreatment of Si doping, the growth of the In gradually reduced In_X Ga_1-X layer, the growth of the In gradual increase of the In_y N_1-y layer, and the growth of the In constant In_z Al₁ -_z layer, Mg diffusion treatment, growth of GaN barrier layer and InGaN:Mg/Si protective layer, the number of cycles is 3-10.

优选地，所述处理衬底的具体过程为：Preferably, the specific process of processing the substrate is:

在1000-1100℃的温度下，通入100-130L/min的H₂，保持反应腔压力100-300mbar，处理蓝宝石衬底5-10min。At a temperature of 1000-1100° C., 100-130 L/min of H₂ was introduced, and the pressure of the reaction chamber was maintained at 100-300 mbar, and the sapphire substrate was treated for 5-10 minutes.

优选地，所述生长低温GaN缓冲层的具体过程为：Preferably, the specific process of growing the low temperature GaN buffer layer is:

降温至500-600℃，保持反应腔压力300-600mbar，通入流量为10000-20000sccm的NH₃、50-100sccm的TMGa及100-130L/min的H₂，在蓝宝石衬底上生长厚度为20-40nm的低温GaN缓冲层；Cool down to 500-600 ℃, keep the pressure of the reaction chamber at 300-600 mbar, pass in NH₃ with a flow rate of 10000-20000 sccm, TMGa with a flow rate of 50-100 sccm and H₂ with a thickness of 100-130 L/min, and grow on a sapphire substrate with a thickness of 20 -40nm low temperature GaN buffer layer;

升高温度到1000-1100℃，保持反应腔压力300-600mbar，通入流量为30000-40000sccm的NH₃、100-130L/min的H₂，保温300-500s，将低温GaN缓冲层腐蚀成不规则岛形。Raise the temperature to 1000-1100°C, keep the pressure of the reaction chamber at 300-600mbar, pass in NH₃ with a flow rate of 30,000-40,000sccm, and H₂ with a flow rate of 100-130L/min, keep the temperature for 300-500s, and etch the low-temperature GaN buffer layer into a stable state. Regular island shape.

优选地，所述生长不掺杂GaN层的具体过程为：Preferably, the specific process of growing the undoped GaN layer is:

升高温度到1000-1200℃，保持反应腔压力300-600mbar，通入流量为30000-40000sccm的NH₃、200-400sccm的TMGa及100-130L/min的H₂，持续生长2-4μm的不掺杂GaN层。Raise the temperature to 1000-1200 ℃, keep the pressure of the reaction chamber at 300-600 mbar, pass in NH₃ with a flow rate of 30,000-40,000 sccm, TMGa with a flow rate of 200-400 sccm and H₂ with a flow rate of 100-130 L/min, and continue to grow 2-4 μm of non-ferrous material. Doped GaN layer.

优选地，所述生长掺杂Si的N型GaN层的具体过程为：Preferably, the specific process of growing the Si-doped N-type GaN layer is:

保持反应腔压力300-600mbar，保持温度1000-1200℃，通入流量为30000-60000sccm的NH₃、200-400sccm的TMGa、100-130L/min的H₂及20-50sccm的SiH₄，持续生长3-4μm掺杂Si的N型GaN，其中，Si掺杂浓度5E18-1E19atoms/cm³。Keep the pressure of the reaction chamber at 300-600mbar, keep the temperature at 1000-1200°C, and feed NH₃ with a flow rate of 30,000-60,000 sccm, TMGa with a flow rate of 200-400 sccm, H₂ with a flow rate of 100-130 L/min and SiH₄ with a flow rate of 20-50 sccm, and continue to grow 3-4 μm Si-doped N-type GaN, wherein the Si doping concentration is 5E18-1E19 atoms/cm³ .

优选地，所述生长AlGaN电子阻挡层的具体过程为：Preferably, the specific process of growing the AlGaN electron blocking layer is:

在温度为900-950℃，反应腔压力为200-400mbar，通入50000-70000sccm的NH₃、30-60sccm的TMGa、100-130L/min的H₂、100-130sccm的TMAl、1000-1300sccm的Cp₂Mg的条件下，生长所述AlGaN电子阻挡层，所述AlGaN层的厚度为40-60nm，其中，Mg掺杂的浓度为1E19-1E20atoms/cm³。At the temperature of 900-950℃, the pressure of the reaction chamber is 200-400mbar, 50000-70000sccm of NH₃ , 30-60 sccm of TMGa, 100-130 L/min of H₂ , 100-130 sccm of TMAl, 1000-1300 sccm of H2 The AlGaN electron blocking layer is grown under the condition of Cp₂ Mg, the thickness of the AlGaN layer is 40-60 nm, and the concentration of Mg doping is 1E19-1E20 atoms/cm³ .

优选地，所述生长掺Mg的P型GaN层的具体过程为：Preferably, the specific process of growing the Mg-doped P-type GaN layer is:

保持反应腔压力400-900mbar、温度950-1000℃，通入流量为50000-70000sccm的NH₃、20-100sccm的TMGa、100-130L/min的H₂及1000-3000sccm的Cp₂Mg，持续生长50-200nm的掺Mg的P型GaN层，其中，Mg掺杂浓度1E19-1E20atoms/cm³。Keep the pressure of the reaction chamber at 400-900 mbar, the temperature at 950-1000 °C, and the flow rate of 50000-70000 sccm of NH₃ , 20-100 sccm of TMGa, 100-130 L/min of H₂ and 1000-3000 sccm of Cp₂ Mg, continuous growth 50-200 nm Mg-doped P-type GaN layer, wherein the Mg doping concentration is 1E19-1E20 atoms/cm³ .

优选地，所述降温冷却的具体过程为：Preferably, the specific process of cooling down is:

降温至650-680℃，保温20-30min，关闭加热系统、关闭给气系统，随炉冷却。Cool down to 650-680℃, keep the temperature for 20-30min, turn off the heating system, turn off the gas supply system, and cool with the furnace.

相比于传统的生长方法，本发明中的减少LED发光波长蓝移量的外延生长方法达到了如下效果：Compared with the traditional growth method, the epitaxial growth method for reducing the blue shift of the LED emission wavelength in the present invention achieves the following effects:

1、本发明的多量子阱发光层生长方法中通过在InGaN阱层和GaN垒层插入In渐变减少In_XGa_1-X层、In渐变增加In_yN_1-y层以及In恒定In_zAl_1-z层，插入层的晶格常数可以与InGaN阱层形成良好的匹配，可以有效缓解InGaN阱层和GaN垒层之间的晶格失配，减少由于晶格失配而产生的压力，避免在压力作用下出现压电极化，减少内部电场，减少量子阱中的能带倾斜，从而减少LED发光波长的蓝移量。另外，生长In掺杂量恒定In_zAl_1-z层，使得多量子阱中空穴和电子的分布中心轴重叠，提高电子向空穴跃迁的效率，从而提高了LED芯片的发光效率。1. In the growth method of the multi-quantum well light-emitting layer of the present invention, the In gradation reduction In_X Ga_1-X layer, the In gradation increase In_y N_1-y layer and the In constant In_z Al layer are inserted into the InGaN well layer and the GaN barrier layer._1-z layer, the lattice constant of the insertion layer can form a good match with the InGaN well layer, which can effectively alleviate the lattice mismatch between the InGaN well layer and the GaN barrier layer, and reduce the stress caused by the lattice mismatch, Avoid piezoelectric polarization under pressure, reduce the internal electric field, and reduce the energy band tilt in the quantum well, thereby reducing the blue-shift of the LED light-emitting wavelength. In addition, growing an In_z Al_1-z layer with a constant In doping amount makes the distribution center axes of holes and electrons in the multiple quantum well overlap, improving the efficiency of electron-to-hole transition, thereby improving the luminous efficiency of the LED chip.

2、本发明的多量子阱发光层生长方法中通过在生长GaN垒层之前进行Mg扩散处理，通过扩散的方式Mg更好地取代Ga位，减少了填充类型的Mg原子，使得并入的Mg原子大部分处在Ga位，提高了处于Ga位Mg原子的比例，使得电离能低的Mg原子比例增加，Mg的电离率相应增加，另一方面通过扩散的方式，取代Ga位的Mg比例增加，该类Mg原子键位饱和Mg和H键结合的几率减少，Mg的电离率相应的提高，从而提高空穴浓度，提升LED的发光效率。2. In the multi-quantum well light-emitting layer growth method of the present invention, the Mg diffusion treatment is performed before the growth of the GaN barrier layer, and the Ga site is better replaced by Mg through diffusion, which reduces the filling type of Mg atoms, so that the incorporated Mg Most of the atoms are in Ga sites, which increases the proportion of Mg atoms in Ga sites, so that the proportion of Mg atoms with low ionization energy increases, and the ionization rate of Mg increases accordingly. On the other hand, through diffusion, the proportion of Mg that replaces Ga sites increases. , the probability of such Mg atomic bonds saturating Mg and H bonds is reduced, and the ionization rate of Mg is correspondingly increased, thereby increasing the hole concentration and improving the luminous efficiency of the LED.

3、在生长垒层之后再生长一层InGaN：Mg/Si保护层，并严格控制Mg和Si的掺杂比例，可以很好地保护发光量子阱，阻碍电荷径向移动，使电荷向四周扩散，即加强电流横向扩展能力，从而提高LED发光效率，并且正向驱动电压更低，波长蓝移量更小。3. A layer of InGaN:Mg/Si protective layer is grown after the growth barrier layer, and the doping ratio of Mg and Si is strictly controlled, which can well protect the light-emitting quantum well, hinder the radial movement of charges, and make the charges diffuse around. , that is, to enhance the lateral expansion capability of the current, thereby improving the luminous efficiency of the LED, and the forward driving voltage is lower, and the wavelength blue shift is smaller.

4、本发明的多量子阱发光层生长方法中通过在量子阱层中引入掺Si预处理的步骤，一方面可以降低驱动电压，并可以增加电子浓度，提高电子的注入，使得器件的总体光效提到提升。另一方面可以改善量子阱的结晶质量降低位错密度，为LED器件发光有源区提供更多的空穴-电子对，提高复合几率，提升亮度，从而改善LED器件的光电性能。4. In the multi-quantum well light-emitting layer growth method of the present invention, by introducing the step of Si-doped pretreatment in the quantum well layer, on the one hand, the driving voltage can be reduced, the electron concentration can be increased, and the injection of electrons can be improved, so that the overall light of the device can be improved. Efficiency refers to improvement. On the other hand, it can improve the crystal quality of the quantum well and reduce the dislocation density, provide more hole-electron pairs for the light-emitting active region of the LED device, increase the recombination probability, and improve the brightness, thereby improving the optoelectronic performance of the LED device.

附图说明Description of drawings

此处所说明的附图用来提供对本发明的进一步理解，构成本发明的一部分，本发明的示意性实施例及其说明用于解释本发明，并不构成对本发明的不当限定。在附图中：The accompanying drawings described herein are used to provide further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the attached image:

图1为本发明方法制备的LED外延的结构示意图；1 is a schematic structural diagram of the LED epitaxy prepared by the method of the present invention;

图2为现有传统方法制备的LED外延的结构示意图；2 is a schematic structural diagram of an LED epitaxy prepared by an existing traditional method;

其中，1、蓝宝石衬底，2、低温GaN缓冲层，3、不掺杂GaN层，4、N型GaN层，5、多量子阱发光层，6、AlGaN电子阻挡层，7、P型GaN层，51、InGaN阱层，52、In渐变减少In_XGa_1-X层，53、In渐变增加In_yN_1-y层，54、In恒定In_zAl_1-z层，55、GaN垒层，56、InGaN：Mg/Si保护层。Among them, 1. Sapphire substrate, 2. Low temperature GaN buffer layer, 3. Undoped GaN layer, 4. N-type GaN layer, 5. Multiple quantum well light-emitting layer, 6. AlGaN electron blocking layer, 7. P-type GaN layer layer, 51, InGaN well layer, 52, In graded decrease InXGa1_-Xlayer , 53, In graded increase InyN1_-ylayer , 54, In constant InzAl1_-zlayer , 55, GaN barrier layer, 56, InGaN: Mg/Si protective layer.

具体实施方式Detailed ways

如在说明书及权利要求当中使用了某些词汇来指称特定组件。本领域技术人员应可理解，硬件制造商可能会用不同名词来称呼同一个组件。本说明书及权利要求并不以名称的差异来作为区分组件的方式，而是以组件在功能上的差异来作为区分的准则。如在通篇说明书及权利要求当中所提及的“包含”为一开放式用语，故应解释成“包含但不限定于”。“大致”是指在可接收的误差范围内，本领域技术人员能够在一定误差范围内解决所述技术问题，基本达到所述技术效果。说明书后续描述为实施本申请的较佳实施方式，然所述描述乃以说明本申请的一般原则为目的，并非用以限定本申请的范围。本申请的保护范围当视所附权利要求所界定者为准。As used in the specification and claims, certain terms are used to refer to particular components. It should be understood by those skilled in the art that hardware manufacturers may refer to the same component by different nouns. The description and claims do not use the difference in name as a way to distinguish components, but use the difference in function of the components as a criterion for distinguishing. As mentioned in the entire specification and claims, "comprising" is an open-ended term, so it should be interpreted as "including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range, and basically achieve the technical effect. Subsequent descriptions in the specification are preferred embodiments for implementing the present application, however, the descriptions are for the purpose of illustrating the general principles of the present application and are not intended to limit the scope of the present application. The scope of protection of this application should be determined by the appended claims.

另外，本说明书并没有将权利要求书公开的构件和方法步骤限定于实施方式的构件和方法步骤。特别是，在实施方式中记载的结构部件的尺寸、材质、形状、其结构顺序和邻接顺序以及制造方法等只要没有具体的限定，就仅作为说明例，而不是将本发明的范围限定于此。附图中所示的结构部件的大小和位置关系是为了清楚地进行说明而放大示出。In addition, the present specification does not limit the components and method steps disclosed in the claims to the components and method steps of the embodiments. In particular, the dimensions, materials, shapes, structural order, adjoining order, and manufacturing methods of the components described in the embodiments are merely illustrative examples, and do not limit the scope of the present invention, unless they are specifically limited. . The size and positional relationship of the structural components shown in the drawings are exaggerated for clarity of explanation.

以下结合附图对本申请作进一步详细说明，但不作为对本申请的限定。The present application will be described in further detail below with reference to the accompanying drawings, but it is not intended to limit the present application.

实施例1Example 1

本实施例采用本发明提供的减少LED发光波长蓝移量的LED外延生长方法，采用MOCVD来生长GaN基LED外延片，采用高纯H₂或高纯N₂或高纯H₂和高纯N₂的混合气体作为载气，高纯NH₃作为N源，金属有机源三甲基镓(TMGa)作为镓源，三甲基铟(TMIn)作为铟源，N型掺杂剂为硅烷(SiH₄)，三甲基铝(TMAl)作为铝源，P型掺杂剂为二茂镁(CP₂Mg)，反应压力在70mbar到900mbar之间。具体生长方式如下(外延结构请参考图1)：This embodiment adopts the LED epitaxial growth method provided by the present invention to reduce the blue shift of the LED emission wavelength, adopts MOCVD to grow a GaN-based LED epitaxial wafer, and adopts high-purity H₂ or high-purity N₂ or high-purity H₂ and high-purity N₂ as the carrier gas, high_- purity NH as the N source, metal organic source trimethylgallium (TMGa) as the gallium source, trimethylindium (TMIn) as the indium source, and N-type dopant as silane (SiH₄ ), trimethylaluminum (TMAl) is used as the aluminum source, the P-type dopant is dicocene (CP₂ Mg), and the reaction pressure is between 70 mbar and 900 mbar. The specific growth method is as follows (for the epitaxial structure, please refer to Figure 1):

一种减少LED发光波长蓝移量的LED外延生长方法，依次包括：处理蓝宝石衬底1、生长低温GaN缓冲层2、生长不掺杂GaN层3、生长掺杂Si的N型GaN层4、生长多量子阱发光层5、生长AlGaN电子阻挡层6、生长掺杂Mg的P型GaN层7，降温冷却；其中，An LED epitaxial growth method for reducing the blue-shift of the LED light-emitting wavelength, which sequentially includes: processing asapphire substrate 1, growing a low-temperatureGaN buffer layer 2, growing anundoped GaN layer 3, growing a Si-doped N-type GaN layer 4, The multi-quantum well light-emittinglayer 5 is grown, the AlGaNelectron blocking layer 6 is grown, the Mg-doped P-type GaN layer 7 is grown, and the temperature is lowered and cooled; wherein,

步骤1：处理蓝宝石衬底1。Step 1: Processing thesapphire substrate 1 .

具体地，所述步骤1，进一步为：Specifically, thestep 1 is further:

在温度为1000-1100℃，反应腔压力为100-300mbar，通入100-130L/min的H₂的条件下，处理蓝宝石衬底5-10分钟。The sapphire substrate is treated for 5-10 minutes under the conditions that the temperature is 1000-1100° C., the pressure of the reaction chamber is 100-300 mbar, and 100-130 L/min of H₂ is introduced.

步骤2：生长低温GaN缓冲层2，并在所述低温GaN缓冲层2形成不规则小岛。Step 2: growing a low temperatureGaN buffer layer 2, and forming irregular islands in the low temperatureGaN buffer layer 2.

具体地，所述步骤2，进一步为：Specifically, thestep 2 is further:

在温度为500-600℃，反应腔压力为300-600mbar，通入10000-20000sccm的NH₃、50-100sccm的TMGa、100-130L/min的H₂的条件下，在所述蓝宝石衬底上生长所述低温GaN缓冲层2，所述低温GaN缓冲层2的厚度为20-40nm；On the sapphire substrate, the temperature is 500-600 ℃, the pressure of the reaction chamber is 300-600 mbar, NH₃ of 10,000-20,000 sccm, TMGa of 50-100 sccm, and H₂ of 100-130 L/min are fed into the sapphire substrate. growing the low temperatureGaN buffer layer 2, the thickness of the low temperatureGaN buffer layer 2 is 20-40nm;

在温度为1000-1100℃、反应腔压力为300-600mbar，通入30000-40000sccm的NH₃、100-130L/min的H₂的条件下，在所述低温GaN缓冲层2上形成所述不规则小岛。Under the conditions that the temperature is 1000-1100° C., the pressure of the reaction chamber is 300-600 mbar, the NH₃ of 30,000-40,000 sccm and the H₂ of 100-130 L/min are fed into the low-temperatureGaN buffer layer 2 to form the non-ferrous metal. Isle of rules.

步骤3：生长不掺杂GaN层3。Step 3: Growth ofundoped GaN layer 3 .

具体地，所述步骤3，进一步为：Specifically, thestep 3 is further:

在温度为1000-1200℃，反应腔压力为300-600mbar，通入30000-40000sccm的NH₃、200-400sccm的TMGa、100-130L/min的H₂的条件下，生长所述不掺杂GaN层3；所述不掺杂GaN层3的厚度为2-4μm。The undoped GaN is grown under the conditions that the temperature is 1000-1200 ℃, the pressure of the reaction chamber is 300-600 mbar, NH₃ of 30,000-40,000 sccm, TMGa of 200-400 sccm, and H₂ of 100-130 L/min are passed through.Layer 3; the thickness of theundoped GaN layer 3 is 2-4 μm.

步骤4：生长Si掺杂的N型GaN层4。Step 4: Growth of Si-doped N-type GaN layer 4 .

具体地，所述步骤4，进一步为：Specifically, thestep 4 is further:

保持反应腔压力300-600mbar，保持温度1000-1200℃，通入流量为30000-60000sccm的NH₃、200-400sccm的TMGa、100-130L/min的H₂及20-50sccm的SiH₄，持续生长3-4μm掺杂Si的N型GaN层4，其中，Si掺杂浓度5E18-1E19atoms/cm³。Keep the pressure of the reaction chamber at 300-600mbar, keep the temperature at 1000-1200°C, and feed NH₃ with a flow rate of 30,000-60,000 sccm, TMGa with a flow rate of 200-400 sccm, H₂ with a flow rate of 100-130 L/min and SiH₄ with a flow rate of 20-50 sccm, and continue to grow 3-4 μm Si-doped N-type GaN layer 4, wherein the Si doping concentration is 5E18-1E19 atoms/cm³ .

步骤5：生长多量子阱发光层5。Step 5: growing the multiple quantum well light-emittinglayer 5 .

所述生长多量子阱发光层5，进一步为：The growth of the multiple quantum well light-emittinglayer 5 is further:

A、控制反应腔压力280-350mbar，控制反应腔温度800-850℃，通入流量为50000-70000sccm的NH₃、20-40sccm的TMGa、10000-15000sccm的TMIn，生长厚度为3nm的InGaN阱层51；A. Control the pressure of the reaction chamber to 280-350 mbar, control the temperature of the reaction chamber to 800-850 ℃, pass in NH₃ with a flow rate of 50,000-70,000 sccm, TMGa with a flow rate of 20-40 sccm, and TMIn with a thickness of 10,000-15,000 sccm, and grow an InGaN well layer with a thickness of 3 nm. 51;

B、保持反应腔的温度和压力不变，通入NH₃、SiH₄、TMIn，关闭TMGa，做5-10秒掺Si预处理；B. Keep the temperature and pressure of the reaction chamber unchanged, pass in NH₃ , SiH₄ , TMIn, turn off TMGa, and do Si doping pretreatment for 5-10 seconds;

C、控制反应腔的温度和压力不变，关闭SiH₄，通入TMGa和TMIn，生长3-7nm的In_XGa_1-X层52，其中X的范围为0.1-0.15，生长过程中控制In的掺杂浓度由1E21 atom/cm³均匀渐变减少至1E20 atom/cm³；C. Control the temperature and pressure of the reaction chamber to remain unchanged, turn off SiH₄ , pass in TMGa and TMIn, and grow a 3-7nm In_X Ga_1-X layer 52, where X is in the range of 0.1-0.15, and control In during the growth process The doping concentration is uniformly reduced from 1E21 atom/cm³ to 1E20 atom/cm³ ;

D、反应腔的压力保持不变，将反应腔温度升高至900-950℃，关闭TMGa，通入NH₃和TMIn，生长10-15nm的In_yN_1-y层53，其中y的范围为0.2-0.25，生长过程中控制In的掺杂浓度由1E20 atom/cm³均匀渐变增加至1E21 atom/cm³；D. The pressure of the reaction chamber remains unchanged, the temperature of the reaction chamber is increased to 900-950 ° C, the TMGa is turned off, NH₃ and TMIn are passed in, and a 10-15 nm In_y N_1-y layer 53 is grown, where the range of y is 0.2-0.25, and the doping concentration of In during the growth process is controlled to increase uniformly and gradually from 1E20 atom/cm³ to 1E21 atom/cm³ ;

E、升温至1000～1050℃，反应腔压力维持在200～300mbar，关闭TMIn，通入NH₃和TMAl，生长5-10nm的In_zAl_1-z层54，其中Z的范围为0.2-0.3，生长过程中控制In的掺杂浓度恒定为2E20 atom/cm³；E. The temperature is raised to 1000-1050°C, the pressure of the reaction chamber is maintained at 200-300 mbar, TMIn is turned off, NH₃ and TMAl are passed in, and a 5-10 nm In_z Al_1-z layer 54 is grown, wherein the range of Z is 0.2-0.3 , during the growth process, the doping concentration of In is controlled to be constant 2E20 atom/cm³ ;

F、控制反应腔的温度和压力不变，停止通入TMAl，保持NH₃气的通入，并通入Cp₂Mg进行Mg扩散处理，处理过程中控制Mg的掺杂浓度由2E21 atom/cm³均匀的变化到3E22atom/cm³，Mg扩散处理时间为15-20s；F. Control the temperature and pressure of the reaction chamber to remain unchanged, stop the introduction of TMAl, keep the introduction of NH₃ gas, and introduce Cp₂ Mg for Mg diffusion treatment. During the treatment process, control the doping concentration of Mg from 2E21 atom/cm³ uniform change to 3E22atom/cm³ , the Mg diffusion treatment time is 15-20s;

G、保持反应腔压力不变，降低反应腔温度至700-750℃，通入流量为30000-40000sccm的NH₃、20-60sccm的TMGa及100-130L/min的N₂，生长10nm的GaN垒层55；G. Keep the pressure of the reaction chamber unchanged, reduce the temperature of the reaction chamber to 700-750 ℃, pass in NH₃ with a flow rate of 30000-40000 sccm, TMGa with a flow rate of 20-60 sccm and N₂ with a flow rate of 100-130 L/min, and grow a 10 nmGaN barrier layer 55;

H、保持反应腔压力不变，升高反应腔温度至780-820℃，通入流量为36000-40000sccm的NH₃、80-100sccm的TMGa、4000-5000sccm的TMIn以及Cp₂Mg和SiH₄，生长厚度为2.5-3.5nm的InGaN：Mg/Si保护层56，其中，Mg和Si的掺杂比例为1:1.5；H. Keep the pressure of the reaction chamber unchanged, raise the temperature of the reaction chamber to 780-820 ℃, and feed NH₃ with a flow rate of 36000-40000 sccm, TMGa with a flow rate of 80-100 sccm, TMIn with a flow rate of 4000-5000 sccm, Cp₂ Mg and SiH₄ , growing an InGaN:Mg/Siprotective layer 56 with a thickness of 2.5-3.5nm, wherein the doping ratio of Mg and Si is 1:1.5;

重复上述步骤A-H，周期性依次进行生长InGaN阱层51、掺Si预处理、生长In渐变减少In_XGa_1-X层52、生长In渐变增加In_yN_1-y层53、生长In恒定In_zAl_1-z层54、Mg扩散处理、生长GaN垒层55和InGaN：Mg/Si保护层56，周期数为3-10个。Repeating the above steps AH, periodically and sequentially growing the InGaN welllayer 51, doping Si pretreatment, growing the In gradually decreasing In_X Ga_1-X layer 52, growing the In gradually increasing the In_y N_1-y layer 53, and growing the In constant In_z Al_1-z layer 54, Mg diffusion treatment, growth ofGaN barrier layer 55 and InGaN:Mg/Siprotective layer 56, the number of cycles is 3-10.

步骤6：生长AlGaN电子阻挡层6；Step 6: growing the AlGaNelectron blocking layer 6;

具体地，所述步骤6，进一步为：Specifically, thestep 6 is further:

在温度为900-950℃，反应腔压力为200-400mbar，通入50000-70000sccm的NH₃、30-60sccm的TMGa、100-130L/min的H₂、100-130sccm的TMAl、1000-1300sccm的Cp₂Mg的条件下，生长所述AlGaN电子阻挡层6，所述AlGaN层6的厚度为40-60nm，其中，Mg掺杂的浓度为1E19-1E20atoms/cm³。At the temperature of 900-950℃, the pressure of the reaction chamber is 200-400mbar, 50000-70000sccm of NH₃ , 30-60 sccm of TMGa, 100-130 L/min of H₂ , 100-130 sccm of TMAl, 1000-1300 sccm of H2 The AlGaNelectron blocking layer 6 is grown under the condition of Cp₂ Mg, the thickness of theAlGaN layer 6 is 40-60 nm, and the concentration of Mg doping is 1E19-1E20 atoms/cm³ .

步骤7：生长Mg掺杂的P型GaN层7。Step 7: Growth of Mg-doped P-type GaN layer 7 .

具体地，所述步骤7，进一步为：Specifically, thestep 7 is further:

在温度为950-1000℃，反应腔压力为400-900mbar，通入50000-70000sccm的NH₃、20-100sccm的TMGa、100-130L/min的H₂、1000-3000sccm的Cp₂Mg的条件下，生长厚度为50-200nm的Mg掺杂P型GaN层7，Mg掺杂浓度1E19-1E20atoms/cm³。Under the conditions that the temperature is 950-1000 ℃, the pressure of the reaction chamber is 400-900 mbar, 50000-70000 sccm of NH₃ , 20-100 sccm of TMGa, 100-130 L/min of H₂ , 1000-3000 sccm of Cp₂ Mg are introduced , a Mg-doped P-type GaN layer 7 with a thickness of 50-200 nm is grown, and the Mg-doped concentration is 1E19-1E20 atoms/cm³ .

步骤8：在温度为650-680℃的条件下保温20-30min，接着关闭加热系统、关闭给气系统，随炉冷却。Step 8: Keep the temperature at 650-680°C for 20-30min, then turn off the heating system, turn off the gas supply system, and cool with the furnace.

实施例2Example 2

以下提供对比实施例，即现有传统LED外延的生长方法。The following provides comparative examples, ie, existing conventional LED epitaxy growth methods.

步骤1：在温度为1000-1100℃，反应腔压力为100-300mbar，通入100-130L/min的H₂的条件下，处理蓝宝石衬底5-10分钟。Step 1: Treat the sapphire substrate for 5-10 minutes under the conditions that the temperature is 1000-1100° C., the pressure of the reaction chamber is 100-300 mbar, and 100-130 L/min of H₂ is introduced.

步骤2：生长低温GaN缓冲层2，并在所述低温GaN缓冲层2形成不规则小岛。Step 2: growing a low temperatureGaN buffer layer 2, and forming irregular islands in the low temperatureGaN buffer layer 2.

具体地，所述步骤2，进一步为：Specifically, thestep 2 is further:

在温度为500-600℃，反应腔压力为300-600mbar，通入10000-20000sccm的NH₃、50-100sccm的TMGa、100-130L/min的H₂的条件下，在所述蓝宝石衬底上生长所述低温GaN缓冲层2，所述低温GaN缓冲层2的厚度为20-40nm；On the sapphire substrate, the temperature is 500-600 ℃, the pressure of the reaction chamber is 300-600 mbar, NH₃ of 10,000-20,000 sccm, TMGa of 50-100 sccm, and H₂ of 100-130 L/min are fed into the sapphire substrate. growing the low temperatureGaN buffer layer 2, the thickness of the low temperatureGaN buffer layer 2 is 20-40nm;

在温度为1000-1100℃、反应腔压力为300-600mbar，通入30000-40000sccm的NH₃、100L/min-130L/min的H₂的条件下，在所述低温GaN缓冲层2上形成所述不规则小岛。Under the conditions of a temperature of 1000-1100° C., a reaction chamber pressure of 300-600 mbar, NH₃ of 30,000-40,000 sccm, and H₂ of 100L/min-130L/min, the low-temperatureGaN buffer layer 2 is formed on the low-temperatureGaN buffer layer 2 . Describe the irregular island.

步骤3：生长不掺杂GaN层3。Step 3: Growth ofundoped GaN layer 3 .

具体地，所述步骤3，进一步为：Specifically, thestep 3 is further:

在温度为1000-1200℃，反应腔压力为300-600mbar，通入30000-40000sccm的NH₃、200-400sccm的TMGa、100-130L/min的H₂的条件下，生长所述不掺杂GaN层3；所述不掺杂GaN层3的厚度为2-4μm。The undoped GaN is grown under the conditions that the temperature is 1000-1200 ℃, the pressure of the reaction chamber is 300-600 mbar, NH₃ of 30,000-40,000 sccm, TMGa of 200-400 sccm, and H₂ of 100-130 L/min are passed through.Layer 3; the thickness of theundoped GaN layer 3 is 2-4 μm.

步骤4：生长Si掺杂的N型GaN层4。Step 4: Growth of Si-doped N-type GaN layer 4 .

具体地，所述步骤4，进一步为：Specifically, thestep 4 is further:

在温度为1000-1200℃，反应腔压力为300-600mbar，通入30000-60000sccm的NH₃、200-400sccm的TMGa、100-130L/min的H₂、20-50sccm的SiH₄的条件下，生长Si掺杂的N型GaN层4，所述N型GaN层4的厚度为3-4μm，Si掺杂的浓度为5E18-1E19atoms/cm³。Under the conditions that the temperature is 1000-1200 ℃, the pressure of the reaction chamber is 300-600 mbar, and NH₃ of 30,000-60,000 sccm, TMGa of 200-400 sccm, H₂ of 100-130 L/min, and SiH₄ of 20-50 sccm are introduced, A Si-doped N-type GaN layer 4 is grown, the thickness of the N-type GaN layer 4 is 3-4 μm, and the concentration of Si doping is 5E18-1E19 atoms/cm³ .

步骤5：生长InGaN/GaN多量子阱发光层5。Step 5: growing the InGaN/GaN multiple quantum well light-emittinglayer 5 .

具体地，所述生长多量子阱发光层，进一步为：Specifically, the growth of the multiple quantum well light-emitting layer is further:

保持反应腔压力300-400mbar、保持温度720℃，通入流量为50000-70000sccm的NH₃、20-40sccm的TMGa、10000-15000sccm的TMIn，生长掺杂In的厚度为3nm的InGaN阱层51；Keep the pressure of the reaction chamber at 300-400 mbar and the temperature at 720 °C, and feed NH₃ with a flow rate of 50,000-70,000 sccm, TMGa with a flow rate of 20-40 sccm, and TMIn with a thickness of 10,000-15,000 sccm, and grow anInGaN well layer 51 doped with In with a thickness of 3 nm;

升高温度至800℃，保持反应腔压力300-400mbar，通入流量为50000-70000sccm的NH₃、20-100sccm的TMGa及100-130L/min的N₂，生长10nm的GaN垒层55；Raise the temperature to 800°C, keep the pressure of the reaction chamber at 300-400mbar, feed NH₃ with a flow rate of 50,000-70,000 sccm, TMGa with a flow rate of 20-100 sccm and N₂ with a flow rate of 100-130 L/min, and grow a 10 nmGaN barrier layer 55;

重复交替生长InGaN阱层51和GaN垒层55，得到InGaN/GaN多量子阱发光层，其中，InGaN阱层51和GaN垒层55的交替生长周期数为7-13个。The InGaN welllayer 51 and theGaN barrier layer 55 are alternately grown repeatedly to obtain an InGaN/GaN multiple quantum well light-emitting layer, wherein the number of alternate growth cycles of the InGaN welllayer 51 and theGaN barrier layer 55 is 7-13.

步骤6：生长AlGaN电子阻挡层6。Step 6: Growth of AlGaNelectron blocking layer 6 .

具体地，所述步骤6，进一步为：Specifically, thestep 6 is further:

在温度为900-950℃，反应腔压力为200-400mbar，通入50000-70000sccm的NH₃、30-60sccm的TMGa、100-130L/min的H₂、100-130sccm的TMAl、1000-1300sccm的Cp₂Mg的条件下，生长所述AlGaN电子阻挡层6，所述AlGaN层6的厚度为40-60nm，其中，Mg掺杂的浓度为1E19-1E20atoms/cm³。At the temperature of 900-950℃, the pressure of the reaction chamber is 200-400mbar, 50000-70000sccm of NH₃ , 30-60 sccm of TMGa, 100-130 L/min of H₂ , 100-130 sccm of TMAl, 1000-1300 sccm of H2 The AlGaNelectron blocking layer 6 is grown under the condition of Cp₂ Mg, the thickness of theAlGaN layer 6 is 40-60 nm, and the concentration of Mg doping is 1E19-1E20 atoms/cm³ .

步骤7：生长Mg掺杂的P型GaN层7。Step 7: Growth of Mg-doped P-type GaN layer 7 .

具体地，所述步骤7，进一步为：Specifically, thestep 7 is further:

在温度为950-1000℃，反应腔压力为400-900mbar，通入50000-70000sccm的NH₃、20-100sccm的TMGa、100-130L/min的H₂、1000-3000sccm的Cp₂Mg的条件下，生长厚度为50-200nm的Mg掺杂P型GaN层7，Mg掺杂浓度1E19-1E20atoms/cm³。Under the conditions that the temperature is 950-1000 ℃, the pressure of the reaction chamber is 400-900 mbar, 50000-70000 sccm of NH₃ , 20-100 sccm of TMGa, 100-130 L/min of H₂ , 1000-3000 sccm of Cp₂ Mg are introduced , a Mg-doped P-type GaN layer 7 with a thickness of 50-200 nm is grown, and the Mg-doped concentration is 1E19-1E20 atoms/cm³ .

步骤8：在温度为650-680℃的条件下保温20-30min，接着关闭加热系统、关闭给气系统，随炉冷却。Step 8: Keep the temperature at 650-680°C for 20-30min, then turn off the heating system, turn off the gas supply system, and cool with the furnace.

根据上述实施例1和实施例2分别制得样品1和样品2，样品1和样品2在相同的前工艺条件下镀ITO层约150nm，相同的条件下镀Cr/Pt/Au电极约1500nm，相同的条件下镀保护层SiO₂约100nm，然后在相同的条件下将样品研磨切割成635μm*635μm(25mil*25mil)的芯片颗粒，之后将样品1和样品2在相同位置各自挑选100颗晶粒，在相同的封装工艺下，封装成白光LED。采用积分球在驱动电流350mA条件下测试样品1和样品2的光电性能。Samples 1 and 2 were prepared according to the above-mentioned Examples 1 and 2, respectively.Samples 1 and 2 were plated with an ITO layer of about 150 nm under the same pre-process conditions, and plated with a Cr/Pt/Au electrode of about 1500 nm under the same conditions. Under the same conditions, the protective layer of SiO₂ is about 100nm, and then the samples are ground and cut into 635μm*635μm (25mil*25mil) chip particles under the same conditions, and then 100 crystals are selected forsample 1 andsample 2 in the same position. The chips are packaged into white LEDs under the same packaging process. The photoelectric properties ofsample 1 andsample 2 were tested by integrating sphere under the condition of driving current of 350mA.

表1样品1和样品2的电性参数比较结果Table 1 Comparison results of electrical parameters ofsample 1 andsample 2

将积分球获得的数据进行分析对比，从表1中可以看出，本发明提供的LED外延生长方法制备的LED(样品1)波长蓝移量更小，并且发光效率得到明显提升，工作更低，抗静电能力更强，这是因为本专利技术方案在量子阱层中引入了掺Si预处理、生长In渐变减少In_XGa_1-X层、生长In渐变增加In_yN_1-y层、生长In恒定In_zAl_1-z层、Mg扩散处理和InGaN：Mg/Si保护层的工艺步骤。The data obtained by the integrating sphere are analyzed and compared. It can be seen from Table 1 that the LED (sample 1) prepared by the LED epitaxial growth method provided by the present invention has a smaller wavelength blue shift, and the luminous efficiency is significantly improved, and the work is lower. , the antistatic ability is stronger, this is because the patented technical solution introduces Si-doped pretreatment in the quantum well layer, the growth of In gradually reduces the In_X Ga_1-X layer, the growth of In gradually increases the In_y N_1-y layer, Process steps for growing In-constant In_z Al_1-z layer, Mg diffusion treatment and InGaN:Mg/Si protective layer.

本发明中的减少LED发光波长蓝移量的LED外延生长方法，跟传统的生长方法相比，达到了如下效果：Compared with the traditional growth method, the LED epitaxial growth method for reducing the blue shift of the LED emission wavelength in the present invention achieves the following effects:

1、本发明的多量子阱发光层生长方法中通过在InGaN阱层和GaN垒层插入In渐变减少In_XGa_1-X层、In渐变增加In_yN_1-y层以及In恒定In_zAl_1-z层，插入层的晶格常数可以与InGaN阱层形成良好的匹配，可以有效缓解InGaN阱层和GaN垒层之间的晶格失配，减少由于晶格失配而产生的压力，避免在压力作用下出现压电极化，减少内部电场，减少量子阱中的能带倾斜，从而减少LED发光波长的蓝移量。另外，生长In掺杂量恒定In_zAl_1-z层，使得多量子阱中空穴和电子的分布中心轴重叠，提高电子向空穴跃迁的效率，从而提高了LED芯片的发光效率。1. In the growth method of the multi-quantum well light-emitting layer of the present invention, the In gradation reduction In_X Ga_1-X layer, the In gradation increase In_y N_1-y layer and the In constant In_z Al layer are inserted into the InGaN well layer and the GaN barrier layer._1-z layer, the lattice constant of the insertion layer can form a good match with the InGaN well layer, which can effectively alleviate the lattice mismatch between the InGaN well layer and the GaN barrier layer, and reduce the stress caused by the lattice mismatch, Avoid piezoelectric polarization under pressure, reduce the internal electric field, and reduce the energy band tilt in the quantum well, thereby reducing the blue-shift of the LED light-emitting wavelength. In addition, growing an In_z Al_1-z layer with a constant In doping amount makes the distribution center axes of holes and electrons in the multiple quantum well overlap, improving the efficiency of electron-to-hole transition, thereby improving the luminous efficiency of the LED chip.

2、本发明的多量子阱发光层生长方法中通过在生长GaN垒层之前进行Mg扩散处理，通过扩散的方式Mg更好地取代Ga位，减少了填充类型的Mg原子，使得并入的Mg原子大部分处在Ga位，提高了处于Ga位Mg原子的比例，使得电离能低的Mg原子比例增加，Mg的电离率相应增加，另一方面通过扩散的方式，取代Ga位的Mg比例增加，该类Mg原子键位饱和Mg和H键结合的几率减少，Mg的电离率相应的提高，从而提高空穴浓度，提升LED的发光效率。2. In the multi-quantum well light-emitting layer growth method of the present invention, the Mg diffusion treatment is performed before the growth of the GaN barrier layer, and the Ga site is better replaced by Mg through diffusion, which reduces the filling type of Mg atoms, so that the incorporated Mg Most of the atoms are in Ga sites, which increases the proportion of Mg atoms in Ga sites, so that the proportion of Mg atoms with low ionization energy increases, and the ionization rate of Mg increases accordingly. On the other hand, through diffusion, the proportion of Mg that replaces Ga sites increases. , the probability of such Mg atomic bonds saturating Mg and H bonds is reduced, and the ionization rate of Mg is correspondingly increased, thereby increasing the hole concentration and improving the luminous efficiency of the LED.

3、在生长垒层之后再生长一层InGaN：Mg/Si保护层，并严格控制Mg和Si的掺杂比例，可以很好地保护发光量子阱，阻碍电荷径向移动，使电荷向四周扩散，即加强电流横向扩展能力，从而提高LED发光效率，并且正向驱动电压更低，波长蓝移量更小。3. A layer of InGaN:Mg/Si protective layer is grown after the growth barrier layer, and the doping ratio of Mg and Si is strictly controlled, which can well protect the light-emitting quantum well, hinder the radial movement of charges, and make the charges diffuse around. , that is, to enhance the lateral expansion capability of the current, thereby improving the luminous efficiency of the LED, and the forward driving voltage is lower, and the wavelength blue shift is smaller.

4、本发明的多量子阱发光层生长方法中通过在量子阱层中引入掺Si预处理的步骤，一方面可以降低驱动电压，并可以增加电子浓度，提高电子的注入，使得器件的总体光效提到提升。另一方面可以改善量子阱的结晶质量降低位错密度，为LED器件发光有源区提供更多的空穴-电子对，提高复合几率，提升亮度，从而改善LED器件的光电性能。4. In the multi-quantum well light-emitting layer growth method of the present invention, by introducing the step of Si-doped pretreatment in the quantum well layer, on the one hand, the driving voltage can be reduced, the electron concentration can be increased, and the injection of electrons can be improved, so that the overall light of the device can be improved. Efficiency refers to improvement. On the other hand, it can improve the crystal quality of the quantum well and reduce the dislocation density, provide more hole-electron pairs for the light-emitting active region of the LED device, increase the recombination probability, and improve the brightness, thereby improving the optoelectronic performance of the LED device.

由于方法部分已经对本申请实施例进行了详细描述，这里对实施例中涉及的结构与方法对应部分的展开描述省略，不再赘述。对于结构中具体内容的描述可参考方法实施例的内容，这里不再具体限定。Since the embodiments of the present application have been described in detail in the method part, the expanded description of the corresponding parts of the structures and methods involved in the embodiments is omitted here, and will not be repeated here. For the description of the specific content in the structure, reference may be made to the content of the method embodiment, which is not specifically limited here.

上述说明示出并描述了本申请的若干优选实施例，但如前所述，应当理解本申请并非局限于本文所披露的形式，不应看作是对其他实施例的排除，而可用于各种其他组合、修改和环境，并能够在本文所述申请构想范围内，通过上述教导或相关领域的技术或知识进行改动。而本领域人员所进行的改动和变化不脱离本申请的精神和范围，则都应在本申请所附权利要求的保护范围内。The above description shows and describes several preferred embodiments of the present application, but as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various various other combinations, modifications and environments, and can be modified within the scope of the concept of the application described herein, using the above teachings or skill or knowledge in the relevant field. However, modifications and changes made by those skilled in the art do not depart from the spirit and scope of the present application, and should all fall within the protection scope of the appended claims of the present application.

Claims (8)

1. An epitaxial growth method for reducing blue shift of LED light-emitting wavelength is characterized by sequentially comprising the following steps: processing a substrate, growing a low-temperature GaN buffer layer, growing an undoped GaN layer, growing an N-type GaN layer doped with Si, growing a multi-quantum well light-emitting layer, growing an AlGaN electron barrier layer, growing a P-type GaN layer doped with Mg, and cooling; the growth multiple quantum well luminescent layer sequentially comprises: growing InGaN well layer, doping Si for pretreatment, growing In for gradually reducing In_XGa_1-XLayer, growing In and gradually increasing In_yN_1-yLayer, growth of In constant In_zAl_1-zLayer, Mg diffusion treatment, growth of GaN barrier layer and InGaN: the Mg/Si protective layer specifically comprises:

A. the pressure of the reaction chamber is controlled to be 280-350mbar, the temperature of the reaction chamber is controlled to be 800-850 ℃, and NH with the flow rate of 50000-70000sccm is introduced₃20-40sccm of TMGa and 10000-15000sccm of TMIn, and growing an InGaN well layer with the thickness of 3 nm;

B. keeping the temperature and the pressure of the reaction chamber unchanged, and introducing NH₃、SiH₄TMIn, and TMGa is closed, and Si-doped pretreatment is carried out for 5-10 seconds;

C. controlling the temperature and the pressure of the reaction chamber to be constant, and closing SiH₄Introducing TMGa and TMIn to grow In 3-7nm_XGa_1-XLayer, wherein X ranges from 0.1 to 0.15, growth processWherein the doping concentration of In is controlled from 1E21atom/cm³Uniformly and gradually reducing to 1E20atom/cm³；

D. Keeping the pressure of the reaction chamber unchanged, raising the temperature of the reaction chamber to 900-₃And TMIn, In of 10-15nm is grown_yN_1-yA layer, wherein y ranges from 0.2 to 0.25, and the doping concentration of In is controlled from 1E20atom/cm during the growth process³The uniform gradual increase is 1E21atom/cm³；

E. Heating to 1000-1050 ℃, keeping the pressure of the reaction cavity at 200-300mbar, closing TMIn, and introducing NH₃And TMAl, growth of 5-10nm In_zAl_1-zA layer, wherein Z is In the range of 0.2-0.3, and the doping concentration of In is controlled to be constant at 2E20atom/cm during the growth process³；

F. Controlling the temperature and the pressure of the reaction cavity to be unchanged, stopping introducing the TMAl and keeping NH₃Introducing gas and introducing Cp₂Mg is subjected to Mg diffusion treatment, and the doping concentration of Mg is controlled to be 2E21atom/cm in the treatment process³Uniform change to 3E22atom/cm³The Mg diffusion treatment time is 15-20 s;

G. keeping the pressure of the reaction chamber unchanged, reducing the temperature of the reaction chamber to 700-₃20-60sccm of TMGa and 100-130L/min of N₂Growing a 10nm GaN barrier layer;

H. keeping the pressure of the reaction cavity unchanged, raising the temperature of the reaction cavity to 780-40000 sccm ℃, and introducing NH with the flow of 36000-40000sccm₃80-100sccm of TMGa, 4000-₂Mg and SiH₄Growing InGaN with a thickness of 2.5-3.5 nm: the Mg/Si protective layer, wherein the doping ratio of Mg to Si is 1: 1.5;

repeating the steps A-H, periodically and sequentially growing an InGaN well layer, doping Si, growing In and gradually reducing In_XGa_1-XLayer, growing In and gradually increasing In_yN_1-yLayer, growth of In constant In_zAl_1-zLayer, Mg diffusion treatment, growth of GaN barrier layer and InGaN: the number of cycles of the Mg/Si protective layer is 3-10.

2. The epitaxial growth method for reducing the blue shift of LED emission wavelength as claimed in claim 1, wherein 100-130L/min H is introduced at a temperature of 1000-1100 ℃₂And processing the sapphire substrate for 5-10min by keeping the pressure of the reaction chamber at 100-.

3. The epitaxial growth method for reducing the blue shift of the LED emission wavelength according to claim 2, wherein the specific process for growing the low-temperature GaN buffer layer is as follows:

cooling to 500-₃TMGa of 50-100sccm and H of 100-₂Growing a low-temperature GaN buffer layer with the thickness of 20-40nm on the sapphire substrate;

raising the temperature to 1000-₃100-130L/min H₂And preserving the heat for 300-500s to etch the low-temperature GaN buffer layer into an irregular island shape.

4. The epitaxial growth method for reducing the blue shift amount of the LED emission wavelength according to claim 1, wherein the specific process for growing the undoped GaN layer is as follows:

raising the temperature to 1000-₃200-400sccm TMGa and 100-130L/min H₂And continuously growing 2-4 mu m undoped GaN layer.

5. The epitaxial growth method for reducing the blue shift amount of the LED emission wavelength according to claim 1, wherein the specific process for growing the Si-doped N-type GaN layer is as follows:

the pressure of the reaction chamber is kept at 300-₃200-400sccm TMGa, 100-130L/min H₂And 20-50sccm SiH₄Continuously growing Si-doped N-type GaN of 3-4 μm, wherein the doping concentration of Si is 5E18-1E19atoms/cm³。

6. The epitaxial growth method for reducing the blue shift amount of the LED emission wavelength according to claim 1, wherein the specific process for growing the AlGaN electron blocking layer is as follows:

introducing NH of 50000-70000sccm at the temperature of 900-950 ℃ and the pressure of the reaction chamber of 200-400mbar₃TMGa 30-60sccm, H100-130L/min₂100 TMAl with 130sccm, 1000 Cp with 1300sccm₂Growing the AlGaN electron barrier layer under the condition of Mg, wherein the thickness of the AlGaN layer is 40-60nm, and the Mg doping concentration is 1E19-1E20atoms/cm³。

7. The epitaxial growth method for reducing the blue shift amount of the LED emission wavelength according to claim 1, wherein the specific process for growing the Mg-doped P-type GaN layer is as follows:

keeping the pressure of the reaction cavity at 400-₃20-100sccm of TMGa, 100-₂And 1000-Cp of 3000sccm₂Mg, continuously growing a P-type GaN layer doped with Mg with the concentration of 50-200nm, wherein the doping concentration of Mg is 1E19-1E20atoms/cm³。

8. The epitaxial growth method for reducing the blue shift amount of the LED luminescence wavelength according to claim 1, wherein the specific cooling process comprises:

cooling to 650 plus 680 ℃, preserving the temperature for 20-30min, closing the heating system and the gas supply system, and cooling along with the furnace.

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