The transfer method of micro- light emitting diode matrixTechnical field
The present invention relates to field of display technology more particularly to a kind of transfer methods of micro- light emitting diode matrix.
Background technique
Micro- light emitting diode (Micro LED) is a kind of device that size arrives between several hundred microns at several microns, due to itIt is much smaller compared with the size of common LED, so that single LED is possibly realized as pixel (Pixel) for showing,Micro light-emitting diode display is that one kind realizes that image is shown using highdensity Micro LED array as display pixel arrayDisplay, it is the same with large-sized outdoor LED display screen, each pixel can addressing, be operated alone and light, can regard asPixel distance is reduced to micron order from grade by the scaled down version of outdoor LED display screen, Micro light-emitting diode display and organicLight emitting diode (Organic Light-Emitting Diode, OLED) display equally belongs to self-emitting display, butMicro light-emitting diode display also has stability of material more preferable, longer life expectancy, askiatic branding etc. excellent compared to OLED displayPoint, it is considered to be the maximum contention opponent of OLED display.
Due to Lattice Matching, Micro LED component first must pass through molecule on the supplying substrate of sapphire classThe method of beam epitaxy grows out, then by laser lift-off (Laser lift-off, LLO) technology that micro- light emitting diode is nakedChip (bare chip) is separated from supplying substrate, then passes through micro- transfer (Micro Transfer Print, NTP) skillArt is transferred into previously prepared circuit pattern of completing and receives on substrate, forms Micro LED array, and then be made intoMicro LED display panel.Wherein, the basic principle of micro- transfer is substantially are as follows: using having patterned transfer head (TransferHead), such as the dimethyl silicone polymer with bulge-structure (Polydimethylsiloxane, PDMS) class transfer head, lead toCross have sticking PDMS transport layer (Transfer layer) by Micro LED bare chip from supplying substrate absorptionCome, then aligns PDMS transfer head with substrate is received, then by the adsorbed Micro LED bare of PDMS transfer headChip, which is attached to, to be received on the preset position of substrate, then Micro can be completed from receiving to remove on substrate in PDMS transfer headThe transfer of LED bare chip forms Micro LED array.
Currently, it is aobvious all once to deliver related Micro LED from Hibernian X-celeprint, texas,U.S university etc.Show the research achievement of device.Apple Inc. causes industry and opens after formal purchase in 2014 has the LuxVue of Micro LED technologyBeginning focuses on the technical advantage of Micro LED, and the high-tech that Micro LED Transfer Printing is grasped as one is publicDepartment, LuxVue and micrometastasis technology difference used in X-Celeprint are larger.X-Celeprint mainly utilizes the films such as PDMSThe adsorption capacity of layer structure carries out transfer action, and LuxVue is adsorbed by being powered in the protrusion of transfer head using electrostatic forceThe devices such as Micro LED.
Wherein, for micro- transfer modes of PDMS class transfer head, since the bulge-structure in PDMS film layer is often through lightThe technological means such as quarter are made, it is characterized in that would become hard to change after the completion of preparation, so that the protrusion row in a kind of PDMS transfer headColumn pattern (Pattern) often corresponds to a kind of micro element (Micro Device) and is receiving the arrangement mode on substrate.So whenWhen being shifted using PDMS class transfer head to Micro LED, since the adhesion strength of PDMS film layer is throughout all approximate, so that oneAfter the patterning of secondary transfer is determined to, other patternings can not be adapted to.
Summary of the invention
The purpose of the present invention is to provide a kind of transfer methods of micro- light emitting diode matrix, and the same PDMS can be used to passThe micro- light emitting diode matrix for sending head to transfer different arrangement modes on receiving substrate.
To achieve the above object, the present invention provides a kind of transfer methods of micro- light emitting diode matrix, including walk as followsIt is rapid:
Step 1 provides transfer head and carrier substrate, and the carrier substrate is equipped with several micro- light emitting diodes, utilizes instituteIt states transfer head and picks up micro- light emitting diode on the carrier substrate；
Step 2, offer receive substrate, in the receiving protrusion for receiving to form several array arrangements on substrate；
Step 3 aligns the transfer head for being loaded with micro- light emitting diode and the substrate that receives, will be micro- in transfer headLight emitting diode is placed in corresponding receiving protrusion, so that corresponding several array arrangement modes for receiving protrusion, are completedThe transfer of micro- light emitting diode matrix.
The material of receiving protrusion formed in the step 2 is silicon nitride or silica.
The height of receiving protrusion formed in the step 2 is 0.01 μm -100 μm.
In the step 2, receive to form several receiving protrusions on substrate described using photoetching process.
The step 2 further includes in the receiving protrusion and receiving to form conducting wire on substrate by photoetching process.
The material of the conducting wire is tin indium oxide.
The step 2 further includes that low melting point pad is arranged on the conducting wire.
Micro- light emitting diode has metal electrode, and the step 3 further includes, described micro- light emitting diode to be placed inAfter receiving protrusion above, heated, so that the low melting point pad on conducting wire melts, thus by the gold of micro- light emitting diodeBelong to electrode to be connected with the conducting wire in the receiving protrusion, and micro- light emitting diode is fixed in the receiving protrusion.
The substrate that receives provided in the step 2 is tft array substrate.
The transfer head is PDMS transfer head, including PDMS film layer, and the PDMS film layer has the convex of several array arrangementsStructure is played, micro- light emitting diode is picked up by the bulge-structure of the PDMS film layer in the step 1.
Beneficial effects of the present invention: the present invention provides a kind of transfer methods of micro- light emitting diode matrix, are receiving baseSeveral receiving protrusions are set on plate, and micro- light emitting diode, which is placed in, to be received to receive in protrusion accordingly on substrate, therefore, for sameOne transfer head is receiving the arrangement mode on substrate by changing several receiving protrusions, just may be implemented in and receive to turn on substratePrint micro- light emitting diode matrix of different arrangement modes.
Detailed description of the invention
For further understanding of the features and technical contents of the present invention, it please refers to below in connection with of the invention detailedIllustrate and attached drawing, however, the drawings only provide reference and explanation, is not intended to limit the present invention.
In attached drawing,
Fig. 1 is the flow diagram of the transfer method of micro- light emitting diode matrix of the invention；
Fig. 2-3 is the schematic diagram of the step 1 of the transfer method of micro- light emitting diode matrix of the invention；
Fig. 4-6 is the schematic diagram of the step 3 of the transfer method of micro- light emitting diode matrix of the invention.
Specific embodiment
Further to illustrate technological means and its effect adopted by the present invention, below in conjunction with preferred implementation of the inventionExample and its attached drawing are described in detail.
Referring to Fig. 1, the present invention provides a kind of transfer method of micro- light emitting diode matrix, include the following steps:
Step 1, as Figure 2-3, provides transfer head 50 and carrier substrate 10, the carrier substrate 10 is equipped with severalMicro- light emitting diode 40 picks up micro- light emitting diode 40 on the carrier substrate 10 using the transfer head 50.
Specifically, the transfer head 50 can be PDMS transfer head, including PDMS film layer, and the PDMS film layer has severalThe bulge-structure 51 of array arrangement, in the step 1 using the bulge-structure 51 of the PDMS film layer by adsorption capacity to describedMicro- light emitting diode 40 is picked up.In addition to this, the transfer head 50 can also be other kinds of transfer head, for example pass throughElectrostatic force is come the transfer head that is picked up.
Specifically, on the carrier substrate 10, micro- light emitting diode 40 has close to the side of carrier substrate 10Metal electrode 41.
Step 2, offer receive substrate 20, in the receiving protrusion 21 for receiving to form several array arrangements on substrate 20.
Specifically, several receiving protrusions 21 are constituted on receiving substrate 20 receives array of protrusions, wherein described severalReceive protrusion 21 and receiving specific arrangement mode on substrate 20 described, according to the micro- of transfer required on receiving substrate 20Depending on the arrangement mode of light emitting diode matrix.
Specifically, the material of receiving protrusion 21 formed in the step 2 is silicon nitride or silica etc..
Specifically, the height of receiving protrusion 21 formed in the step 2 is 0.01 μm -100 μm, so that subsequentMicro- light emitting diode 40 in transfer head 50 is transferred to when receiving substrate 20, the receiving protrusion 21 only received on substrate 20 canIt is contacted with micro- light emitting diode 40, and other parts cannot be contacted with micro- light emitting diode 40, so that 40 quilt of micro- light emitting diodeIt is accordingly placed in receiving protrusion 21.
Specifically, in the step 2, receive to form several receiving protrusions on substrate 20 described using photoetching process21, the photoetching process specifically include light blockage coating, exposure, development and etching and etc..
Specifically, the step 2 further includes conducting wire 22 being formed in the receiving protrusion 21 by photoetching process, in instituteState setting low melting point pad on conducting wire 22.
Specifically, the conducting wire 22 is conductive material, and the material of the conducting wire 22 is preferably tin indium oxide(ITO)。
Step 3, as Figure 4-Figure 6, the transfer head 50 for being loaded with micro- light emitting diode 40 and the substrate 20 that receives are carried outMicro- light emitting diode 40 in transfer head 50 is placed in corresponding receivings protrusion 21 by contraposition, several is connect so that correspondence is describedBy the array arrangement mode of protrusion 21, the transfer of micro- light emitting diode matrix is completed.
Specifically, the step 3 further includes, after micro- light emitting diode 40 being placed in the receiving protrusion 21, intoRow heat treatment, so that the low melting point pad on conducting wire 22 melts, thus by the metal electrode 41 of micro- light emitting diode 40 and instituteIt states the conducting wire 22 received in protrusion 21 to be connected, and micro- light emitting diode 40 is fixed in the receiving protrusion 21.
Specifically, the substrate 20 that receives provided in the step 2 is tft array substrate, thus completing micro- light-emitting diodesAfter the transfer of pipe array, it can be further used for making micro- light emitting diode indicator.
In conclusion being arranged on receiving substrate the present invention provides a kind of transfer method of micro- light emitting diode matrixSeveral receiving protrusions, micro- light emitting diode, which is placed in, to be received to receive in protrusion accordingly on substrate, therefore, for the same transmissionHead is receiving the arrangement mode on substrate by changing several receiving protrusions, just may be implemented in and receive to transfer different rows on substrateMicro- light emitting diode matrix of column mode.
The above for those of ordinary skill in the art can according to the technique and scheme of the present invention and technologyOther various corresponding changes and modifications are made in design, and all these change and modification all should belong to the claims in the present inventionProtection scope.