A kind of welding method and welding system of silicon wafer and glassTechnical field
The invention belongs to laser micro/nano manufacture fields, and in particular to a kind of nanosecond laser is used for plating metal film layerThe welding method and welding system of silicon wafer and glass.
Background technique
The requirement for answering microelectronic component to develop, in order to solve the problems, such as the contact resistance of superlattice semiconductor microcooler,The technology that metal contact membranes are prepared on silicon chip surface has been greatly developed.Monocrystalline silicon has a very wide range of applications, and is electricityIndispensable basic material in the modern science and technology such as sub- computer, automatic control system not only penetrates into people's lifeEach corner, and be space shuttle, spaceship, the essential raw material of artificial satellite, and be widely used inIn solar battery, the beginning for green energy resource revolution of marching toward is realized.Stabilization of the glass due to its good transparency and materialProperty has a wide range of applications in the fields such as production of Electronic Packaging, biochip, precision instrument.
Therefore more stringent requirements are proposed for the bonding techniques of glass and silicon.Existing ultrafast laser for glass andThe welding technique of silicon wafer, the cost is relatively high for machinery equipment, and production efficiency is lower, promotes with being unfavorable for industrialization, especially notApplication field that is of less demanding suitable for processing precise degree, pursuing industrialization economic benefit.
Summary of the invention
In consideration of it, this method can not only it is necessary to provide the welding method of a kind of silicon wafer and glass regarding to the issue aboveReduce processing cost, realize industrialized requirement, and due to plate into metal-plated film layer there are the performances such as fabulous electric conductivity,The technology of laser welding can be applied more broadly in microelectronic component manufacture field, greatly widen answering for this technologyUse range.
The present invention is achieved by the following technical solutions:
A kind of welding method of silicon wafer and glass, comprising the following steps:
S100: plating at least one layer of metal film on silicon wafer, forms metal-plated film layer；
S300: by silicon chip film-coated face and glass gluing；
S400: nanosecond laser welding.
Further, silicon wafer thickness range is 0.5mm~4.1mm in the step S100.
Further, metal-plated thicknesses of layers is 10~1000nm in the step S100.
Further, metal coating can be in the step S100 are as follows: copper film, titanium film, nickel film, aluminium film even alloy filmDeng.
Further, in the step S100, when metal-plated film layer by least double layer of metal film is formed by stacking when, it is describedMetal film can be the metal film of same metal, be also possible to the metal film of different metal.
Further, the method also includes S200: before silicon chip film-coated face and glass gluing, by the anhydrous second of glassAlcohol or acetone soln are cleaned by ultrasonic 2~5 minutes.
Further, thickness of glass range described in the step S300 is 0.1mm~3.1mm.
Further, in the step S300 by the silicon wafer of glass and plated film carry out optical contact processing (using water suction,The mode of extruding excludes the air between two samples, and two interfaces are bonded close by intermolecular Van der Waals force) makeGlass and silicon wafer fitting are close.
Further, the power of the transmitter of nanosecond laser is 10W~20W in the step S400.
Further, the wavelength of laser beam is 355nm~1064nm in the step S400.
Further, the pulse duration range of laser is 50ns~100ns in the step S400.
Further, the direct range of the focal beam spot of laser is 10um~20um in the step S400.
Further, the welding manner of the step S400 is the mode of line processing.
Further, 1~10000mm/s of process velocity of the step S400.
In some embodiments, the silicon wafer in the method can also be substituted for polysilicon, GaAs, phosphorus phosphide, antimonyIt plugs with molten metal, the conventional semiconductor materials such as silicon carbide, cadmium sulfide and gallium arsenic silicon, and including oxide glass and nonoxide glassNoncrystal amorphous semiconductor material substitution.
A kind of silicon and glass solder system, including laser, optic delivery systems, galvanometer scanning system, workbench, toWeld sample；Laser is located at the side of optic delivery systems, and galvanometer scanning system is located at the lower section of optic delivery systems, workMake the lower section that platform is located at galvanometer scanning system, sample to be welded is as the lower section on workbench and positioned at galvanometer scanning system.
Further, the laser is infrared nanosecond laser.
The invention has the advantages that:
The thickness of silicon wafer (or other can substitute the material of silicon wafer) of the present invention, metal-plated film layer and glass is in the present inventionIn disclosed range, it can guarantee that three's thickness, quality match, the service life is longer.
After the surface of silicon wafer (or other can substitute the material of silicon wafer) plates metal film plating layer, with nanosecond laser realityThe welding of existing glass and silicon wafer (or other can substitute the material of silicon wafer) can not only reduce processing cost, realize industrializationIt is required that and due to plate into metal-plated film layer there are the performances such as fabulous electric conductivity, the technology of laser welding can more extensivelyGround is applied to microelectronic component manufacture field, has greatly widened the application range of this technology.
Detailed description of the invention
Fig. 1 is the silicon of the metal-coated membrane of the embodiment of the present invention and the structural schematic diagram of glass solder system；
Fig. 2 is the sample structure schematic diagram to be processed of the embodiment of the present invention；
Fig. 3 is the silicon of the metal-coated membrane of the embodiment of the present invention and the flow chart of glass solder system.
Appended drawing reference: 10- laser, 20- optic delivery systems, 30- galvanometer scanning system, 40- workbench, 50- are to be weldedConnect sample；51- glass, 52- silicon wafer (or other can substitute the material of silicon wafer), 53- metal-plated film layer, 54- laser action areaDomain.
Specific embodiment
Technical solution problem to be solved, the technical solution of use and what is reached have in order to better illustrate the present inventionBeneficial effect, is further described now in conjunction with specific embodiment.It is worth noting that technical solution of the present invention including but not limited toFollowing implementation.
Particular technique or condition are not specified in the embodiment of the present invention, according to the literature in the art described technologyOr it condition or is carried out according to product description.Reagents or instruments used without specified manufacturer, being can be by commercially availableEtc. approach obtain conventional products.
The welding method of embodiment 1 silicon wafer of the invention and glass
The following steps are included:
S100: the metal-plated film layer 53 of 10~1000nm thickness is plated on the silicon wafer 52 of 0.5mm~4.1mm thickness；
S200: the dehydrated alcohol of glass 51 or acetone soln are cleaned by ultrasonic 2~5 minutes；
S300: the coated surface of the glass 51 of S200 and silicon wafer 52 is subjected to optical contact processing, is bonded the two；
S400: it is welded in silicon and glass solder system with the material that nanosecond laser is bonded step (2).
In some embodiments, the metal-plated film layer 53 can be copper film, titanium film, nickel film, aluminium film etc..
In some embodiments, the metal-plated film layer 53 in the step S100 is formed by stacking by least one layer of metal film；When metal-plated film layer 53 by least double layer of metal film is formed by stacking when, at least two layers of the metal film can be identical goldBelong to film, is also possible to different metal films.
In some embodiments, the power of the transmitter (i.e. laser 10) of nanosecond laser is 10W in the step S400Any value between~20W.
In some embodiments, the wavelength of laser beam any value between 355nm-~1064nm in the step S400.
In some embodiments, the pulse duration range of laser any value between 50ns~100ns in the step S400.
In some embodiments, in the step S400 the direct range of the focal beam spot of laser between 10um~20umAny value.
In some embodiments, the welding manner of the step S400 is the mode of line processing.
In some embodiments, any value between 1~10000mm/s of process velocity of the step S400.
In some embodiments, the silicon wafer 52 in the method can also be substituted for polysilicon, GaAs, phosphorus phosphide, antimonyThe conventional semiconductor materials such as change plugs with molten metal, silicon carbide, cadmium sulfide and gallium arsenic silicon, and including oxide glass and nonoxide glassNoncrystal amorphous semiconductor material substitution.
It wherein, refering to fig. 1, is silicon described in step S400 (or other can substitute the material of silicon wafer) and glass solderThe structural schematic diagram of system.The silicon (or other can substitute the material of silicon wafer) and glass solder system packet of the embodiment of the present inventionInclude laser 10, optic delivery systems 20, galvanometer scanning system 30, workbench 40, sample to be welded 50；Laser 10 is located atThe side of optic delivery systems 20, galvanometer scanning system 30 are located at the lower section of optic delivery systems 20, and workbench 40 is located at galvanometerThe lower section of scanning system 30, sample 50 to be welded is as the lower section on workbench 40 and positioned at galvanometer scanning system 30.
The silicon (or other can substitute the material of silicon wafer) of the metal-coated membrane of the embodiment of the present invention and glass solder systemFundamentals of Welding are as follows: laser beam is emitted by laser 10, the laser beam of transmitting is incident to galvanometer after optic delivery systems 20Scanning system 30 is focused processing to laser beam by galvanometer scanning system 30, makes laser beam inside welded workpiece 50Hot spot is formed, and welded workpiece 50 is welded using focal beam spot；Galvanometer scanning system 30 is for different-thicknessWelded workpiece 50 can set corresponding technological parameter and be cut, and technological parameter includes laser power, cutting speed and focusPosition etc.；In laser beam welding, the glass 51 (referring to fig. 2) of the laser beam focus of high-energy density to welded workpiece 50At the interface metal-plated film layer 53 (referring to fig. 2) of silicon wafer 52 (referring to fig. 2) (or other can substitute the material of silicon wafer),Metal material melts after absorbing laser energy, and glass 51 and silicon wafer 52 (or other substitute the material of silicon wafer) are bondedTogether, reach welding effect.
The metal-plated film layer 53 is whole weldings or part with the connection type of semiconductor material layer 52 and glassy layer 51Welding.When the metal-plated film layer 53 is part welding with the connection type of semiconductor material layer 52 and glassy layer 51, laserThe zone of action 54 is metallic film melts join domain；When the metal-plated film layer 53 and semiconductor material layer 52 and glassy layer 51Connection type when being whole weldings, metal connecting layer 53 is metallic film melts join domain.It referring to fig. 2, is metal coatingA kind of embodiment when the connection type of layer 53 and semiconductor material layer 52 and glassy layer 51 is part welding.Some otherIn embodiment, the laser action region 54 can also be circle, polygon or other any desired shapes of arbitrary dimensionDeng.
In embodiments of the present invention, laser 10 is optical fiber infrared laser, and the power of laser 10 is 10W~20W,The wavelength of the emitted laser beam of laser 10 is 1064nm, and pulse duration range is 50ns~100ns, the direct range of focal beam spotIt is to be welded by being realized in a non contact fashion using the lesser pulse width of laser beam and shorter wavelength for 10um~20umThe welding of workpiece 50, since its wavelength is short, hot spot is small, and heat-affected zone is small, obtains the welding processing of high-precision and high qualityEffect.
In embodiments of the present invention, the welded workpiece 50 is glass 51 and the silicon wafer being coated with after metal-plated film layer 53Sample after 52 (or other can substitute the material of silicon wafer) fitting, wherein 51 thickness range of glass is 0.1mm~3.1mm, silicon(or other can substitute the material of the silicon wafer) thickness range of piece 52 is 0.5mm~4.1mm, the metal-plated being plated at 51 burnishing surfaces53 thickness range of film layer is 10nm~1000nm.
It is welded using low-power output laser, laser acts in metal-plated film layer 53 as heating source to be madeGlass 51 and silicon wafer 53 (or other can substitute the material of silicon wafer) bonding are obtained, in addition to the Energy distribution of laser and the shadow of densityOutside ringing, material equally has a huge impact the absorption threshold value of laser to welding effect, therefore comprehensively considers various factors,It chooses laser output power of the invention to process sample, successfully realizes that (or other can be replaced for glass 51 and silicon wafer 52For the material of silicon wafer) bonding.
Metal film is plated on silicon wafer 52 (or other can substitute the material of silicon wafer) by the way of plated film, works as laserWhile acting on metal-plated film layer 53 two materials be welded successfully, enable have film plating layer 53 silicon wafer 52 (or otherSubstitute the material of silicon wafer) realize electricity, magnetic, optical property requirement.(or other can be replaced for glass 51 and silicon wafer 52 after laser actionFor the material of silicon wafer) region that is welded successfully, through glass can be clearly observed silicon wafer 52 after laser action (or itsHe can substitute the material of silicon wafer) on metal-plated film layer 53 in whole or in part dissipate (depending on being whole weldings or partWelding mode), nanosecond laser as heat source make metal-plated film layer 53 completely or partially melting after successfully by glass 51 and siliconPiece 52 (or other can substitute the material of silicon wafer) closely bonds together.
Embodiment 2 welding method welding silicon wafer of the invention and glass
Referring to Fig. 3, be the metal-coated membrane of the embodiment of the present invention silicon 53 (or other can substitute the material of silicon wafer) andThe flow chart of 51 welding method of glass.The following steps are included:
Step S100: it is formed using coating machine in the polished surface of silicon wafer 52 (or other can substitute the material of silicon wafer)The control range of the metal-plated film layer 53 of 50nm thickness, 53 thickness of metal-plated film layer is isolated in 10nm~1000nm, and in timeProcessing, prevents metal-plated film layer 53 to be contaminated and scratch.
Step S200: ultrasonic cleaning is carried out to glass 51, glass 51 is put into dehydrated alcohol or acetone soln and is cleaned2~5 minutes, in order to guarantee that laser enables energy to transmit well between two bonding pads as heating source, it is necessary to make to be bondedPiece can be closely contacted together, its surface of glass 51 after being cleaned with dehydrated alcohol or acetone soln can increase, in comparingStrong hydrophily.
Step S300: by glass 51 and the silicon wafer 52 (or other can substitute the material of silicon wafer) for adding metal-plated film layer 53It fits together at room temperature, optics is carried out to two samples during the bonding process if institute's metal-coated membrane is relatively firmContact treatment, so that two samples are snugly even closer.Hydrogen bond and van der Waals interaction of the sample by interface, without outerPlus-pressure can be in close contact at room temperature together, generated biggish remnants after being bonded to avoid external pressure is applied and answeredPower.Metal-plated film layer 53 is at the interface of glass 51 and silicon wafer 53 (or other can substitute the material of silicon wafer).
Step S400: in silicon 52 (or other can substitute the material of silicon wafer) and 51 welding system of glass, using line plusThe mode of work welds sample, and the controlled range of process velocity is 1~10000mm/s, and adding using the face that is wired toWork mode acts on sample, i.e., arbitrarily controls graphics processing by controlling software, using between suitable filling mode and fillingAway from (using line filling mode, can choose the modes such as S type, linear type, helical ring geometric pattern, be also possible to the folded of several waysAdd；Fill spacing general control in 0.001~0.1mm), so that galvanometer according to design parameter the continuous cabling in the range of work,Complete the welding of entire machining area.
It is flexibly easily operated using laser processing mode, it is low in cost using nanosecond laser, it is easy to industrial applicationsPopularization；On semiconductor material after plating metal film layer, the mode of laser processing is reused, utilizes being heated for metallic diaphragmMelt effect, realizes the successful bonding of semiconductor material and transparent material.This technology is while realizing material binds, laserNeatly processing method can also be according to requiring to process different shape and thickness on metallic diaphragm, relative to traditional for beamChip manufacturing process can design the route on metallic diaphragm, and two kinds of techniques of bonding of material are combined into one, and simplify processingProcess greatly improves production efficiency, while can also mitigate environmental pollution, meets the requirement of energy-saving and environment friendly.
When the welding of the method for the present invention part, by control laser action region 54 shape, obtain meet the requirements it is unmeltedThe shape for the metal-plated film layer 53 melted designs required circuit diagram etc. using 53 region of metal-plated film layer not melted.LaserThe zone of action 54 plays the role of bonding glass 51 and silicon wafer 52, by this method control machined parameters make 53 regions not byDamage.
The welding manner that glass and silicon wafer at most use at present is anodic bonding (300-450 DEG C), overall processing temperature compared withHeight, residual stress is higher, cracked easily on bonding face or even rupture.Office may be implemented in the laser welding that the present invention controlsPortion's high temperature process avoids generating destruction to non-processing region, and in 1mm, glass front is several for the positive ablation influence area of silicon waferIt does not influence, stability, reliability, fatigue durability are all more outstanding.(bonding is strong in 10-20MPa for the tensile strength of anodic bondingDegree is 6.2-9.8MPa), the tensile strength 20-40MPa of laser welding.
The embodiments described above only express several embodiments of the present invention, and the description thereof is more specific and detailed, but simultaneouslyLimitations on the scope of the patent of the present invention therefore cannot be interpreted as.It should be pointed out that for those of ordinary skill in the artFor, without departing from the inventive concept of the premise, various modifications and improvements can be made, these belong to of the inventionProtection scope.Therefore, the scope of protection of the patent of the invention shall be subject to the appended claims.