Supporting substrate for preparing semiconductor light-emitting device and semiconductor light-emitting device using supporting substrates

Abstract

The present invention is related to a supporting substrate for preparing a semiconductor light-emitting device employing a multi-layered light-emitting structure thin-film and a method for preparing a semiconductor light-emitting device employing the supporting substrate for preparing a semiconductor light-emitting device. The supporting substrate for preparing a semiconductor light-emitting device is formed by successively laminating a sacrificial layer, a heat-sink layer and a bonding layer on a selected supporting substrate. A method for preparing a semiconductor light-emitting device employing the supporting substrate for preparing a semiconductor light-emitting device includes: preparing a first wafer in which a semiconductor multi-layered light-emitting structure is laminated/grown on an upper part of an initial substrate; preparing a second wafer which is a supporting substrate for preparing a semiconductor light-emitting device; bonding the second wafer on an upper part of the first wafer; separating the initial substrate of the first wafer from a result of the bonding; performing passivation after forming a first ohmic contact electrode on an upper part of the first wafer from which the initial substrate is separated; and preparing a single-chip by severing a result of the passivation.

1 . A supporting substrate for preparing a semiconductor light-emitting device, comprising:
 a selected supporting substrate formed of an electrically insulating material;   a sacrificial layer formed by being laminated on an upper part of the selected supporting substrate;   a heat-sink layer formed of a metal, an alloy or a solid solution having a high thermal and electrical conductivity and formed on an upper part of the sacrificial layer; and   a bonding layer formed by being laminated on an upper part of the heat-sink layer,   wherein the supporting substrate is used for a supporting substrate of a vertical-structured semiconductor light-emitting device.   
     
     
         2 . The supporting substrate for preparing a semiconductor light-emitting device of  claim 1 , wherein the electrically insulating material of the selected supporting substrate has a difference of thermal expansion coefficient of 2 ppm or less from an initial substrate. 
     
     
         3 . The supporting substrate for preparing a semiconductor light-emitting device of  claim 1 , wherein the electrically insulating material of the selected supporting substrate is a single crystal, polycrystal or amorphous substance selected from the group consisting of sapphire (Al 2 O 3 ), aluminum nitride (AlN), MgO, AlSiC, BN, BeO, TiO 2 , SiO 2  and glass. 
     
     
         4 . The supporting substrate for preparing a semiconductor light-emitting device of  claim 1 , wherein the sacrificial layer is:
 (i) a single crystal, polycrystal or amorphous substance bonded with nitrogen or oxygen, the substance being at least one selected from the group consisting of GaN, InGaN, ZnO, InN, In 2 O 3 , ITO, SnO 2 , Si 3 N 4 , SiO 2 , BeMgO and MgZnO;   (ii) at least one material selected from the group consisting of metals, alloys, solid solutions, oxides, nitrides and thermophile organic materials that can be chemically etched, if the sacrificial layer is composed of materials removable by chemical etching;   (iii) at least one material selected from the group consisting of heat-resistant adhesive, silicone adhesive and polyvinyl butyral resin, if the sacrificial layer is composed of a heat-resistant adhesive material;   (iv) a silicate or a silicic acid material, if the sacrificial layer is an SOG (Spin on Glass) thin film;   (v) at least one selected from the group consisting of silicate, siloxane, methyl silsequioxane (MSQ), hydrogen silsequioxane (HSQ), MQS+HSQ, perhydrosilazane (TCPS) and polysilazane, if the sacrificial layer is an SOD (Spin On Dielectrics); or   (vi) at least one selected from the group consisting of AZ series, SU-8 series, TLOR series, TDMR series, and GXR series if the sacrificial layer is composed of photoresist.   
     
     
         5 . The supporting substrate for preparing a semiconductor light-emitting device of  claim 1 , wherein the thickness of the heat-sink layer is 0.1 μm to 500 μm. 
     
     
         6 . The supporting substrate for preparing a semiconductor light-emitting device of  claim 1 , wherein the metal, alloy or solid solution forming the heat-sink layer comprises at least one selected from the group consisting of Cu, Ni, Ag, Mo, Al, Au, Nb, W, Ti, Cr, Ta, Al, Pd, Pt and Si. 
     
     
         7 . The supporting substrate for preparing a semiconductor light-emitting device of  claim 1 , wherein the bonding layer is a soldering or brazing alloy material comprising at least one selected from the group consisting of Ga, Bi, In, Sn, Pb, Au, Al, Ag, Cu, Ni, Pd, Si and Ge. 
     
     
         8 . The supporting substrate for preparing a semiconductor light-emitting device of  claim 1 , wherein the sacrificial layer, the heat-sink layer and the bonding layer laminated/formed on the upper part of the selected supporting substrate are formed by physical vapor deposition, chemical vapor deposition or electrochemical deposition,
 the sacrificial layer is formed by one method selected from the group consisting of E-beam evaporator, thermal evaporator, MOCVD (Metal Organic Chemical Vapor Deposition), sputtering and PLD (Pulsed Laser Deposition), and   the heat-sink layer is formed by electro plating or electroless plating.   
     
     
         9 . The supporting substrate for preparing a semiconductor light-emitting device of  claim 1 , wherein at least one of the sacrificial layer, the heat-sink layer and the bonding layer of the supporting substrate for preparing a semiconductor light-emitting device is selectively patterned in the form of a predetermined shape, or
 all of the sacrificial layer, the heat-sink layer and the bonding layer of the supporting substrate for preparing a semiconductor light-emitting device are patterned in the form of a predetermined shape, and the selected supporting substrate is etched to a predetermined depth.   
     
     
         10 . The supporting substrate for preparing a semiconductor light-emitting device of  claim 1 , wherein the sacrificial layer is dissolved in a wet etching solution. 
     
     
         11 . A method for preparing a semiconductor light-emitting device, the method comprising:
 (a) preparing a first wafer in which semiconductor multi-layered light-emitting structure is laminated/grown on an upper part of an initial substrate;   (b) preparing a second wafer which is a supporting substrate for preparing a semiconductor light-emitting device;   (c) bonding the second wafer on an upper part of the first wafer;   (d) separating the initial substrate of the first wafer from a result of the bonding;   (e) performing passivation after forming a first ohmic contact electrode on the upper part of the first wafer from which the initial substrate is separated; and   (f) fabricating a single-chip by severing a result of the passivation, wherein the supporting substrate for preparing a semiconductor light-emitting device of the second wafer is formed by successively laminating the sacrificial layer, the heat-sink layer and the bonding layer on the selected supporting substrate.   
     
     
         12 . The method for preparing a semiconductor light-emitting device of  claim 11 , wherein the semiconductor multi-layered light-emitting structure in the step (a) comprises an n-type semiconductor cladding layer, a light-emitting active layer and a p-type semiconductor cladding layer. 
     
     
         13 . The method for preparing a semiconductor light-emitting device of  claim 11 , wherein each layer of the semiconductor multi-layered light-emitting structure in the step (a) is composed of a single crystal of In x (Ga y Al 1-y )N(1=x=0, 1=y=0, x+y>0). 
     
     
         14 . The method for preparing a semiconductor light-emitting device of  claim 11 , wherein the wafer bonding of the step (c) is performed by a thermo compression bonding method at the temperature of 100° C. to 600° C. and the pressure of 1 Mpa to 200 Mpa. 
     
     
         15 . The method for preparing a semiconductor light-emitting device of  claim 11 , wherein the separating of the initial substrate of the first wafer from the bonded result in the step (d) is performed by a method selected from the group consisting of a laser lift-off method irradiating a laser beam to a surface of the initial substrate, a chemo-mechanical polishing method, and a wet etching method using a wet etching solution. 
     
     
         16 . The method for preparing a semiconductor light-emitting device of  claim 11 , wherein the preparing of the semiconductor light-emitting device in a single-chip in the step (f) comprises:
 (f1) attaching a temporary supporting substrate formed of organic or inorganic bonding materials in the opposite direction of the supporting substrate for preparing a semiconductor light-emitting device;   (f2) separating and removing the selected supporting substrate by thermochemical dissociation of the sacrificial layer with an electromagnetic light including a laser beam having an appropriate absorption wavelength range according to a material used for the sacrificial layer; and   (f3) severing a result of the above steps in a vertical direction without any bonding process of the supporting substrate if the thickness of the heat-sink layer is greater than a predetermined value, and forming an additional bonding layer composed of an electrically conductive metal, solid solution or alloy and bonding a third supporting substrate to the heat-sink layer using the additional bonding layer and then severing a result of the forming and bonding in a vertical direction if the thickness of the heat-sink layer is smaller than a predetermined value.   
     
     
         17 . The method for preparing a semiconductor light-emitting device of  claim 16 , wherein the thickness of the heat-sink layer of the supporting substrate for preparing a semiconductor light-emitting device is 80 μm to 500 μm. 
     
     
         18 . The method for preparing a semiconductor light-emitting device of  claim 16 , wherein the third supporting substrate is formed of: a single crystal or polycrystal wafer comprising at least one component selected from the group consisting of Si, Ge, SiGe, ZnO, GaN, AlGaN and GaAs having thermal and electrical conductivity; or a metal, alloy or solid solution foil comprising at least one selected from the group consisting of Mo, Cu, Ni, Nb, Ta, Ti, Au, Ag, Cr, NiCr, CuW, CuMo and NiW. 
     
     
         19 . The method for preparing a semiconductor light-emitting device of  claim 11 , wherein a material for forming the first ohmic contact electrode in the step (e) is composed of a material comprising at least one selected from the group consisting of Al, Ti, Cr, Ta, Ag, Al, Rh, Pt, Au, Cu, Ni, Pd, In, La, Sn, Si, Ge, Zn, Mg, NiCr, PdCr, CrPt, NiTi, TiN, CrN, SiC, SiCN, InN, AlGaN, InGaN, rare earth metals and alloys, metallic silicides, semiconducting silicides, CNTNs (carbonnanotube networks), transparent conducting oxides (TCO) and transparent conducting nitrides (TCN). 
     
     
         20 . The method for preparing a semiconductor light-emitting device of  claim 11 , wherein the first wafer in the step (a) is prepared by forming an optical reflective layer, an electrical insulating layer, a diffusion barrier layer, a heat-sink layer, or a bonding layer on the upper part of the semiconductor multi-layered light-emitting structure laminated and grown on the upper part of the substrate. 
     
     
         21 . The method for preparing a semiconductor light-emitting device of  claim 20 , wherein the electrical insulating layer, the diffusion barrier layer, the heat-sink layer, or the bonding layer on the upper part of the semiconductor multi-layered light-emitting structure is formed by physical vapor deposition, chemical vapor deposition, electro plating or electroless plating. 
     
     
         22 . The method for preparing a semiconductor light-emitting device of  claim 11 , wherein the sacrificial layer laminated on the selected supporting substrate of the second wafer is composed of a material soluble in a wet etching solution, and the sacrificial layer of the supporting substrate for preparing a semiconductor light-emitting device in the step (f) is wet-etched by dissolving the sacrificial layer into a wet etching solution to separate and remove the selected supporting substrate and then a single chip is obtained by severing a result of the separating and removing. 
     
     
         23 . The method for preparing a semiconductor light-emitting device of  claim 11 , wherein the first ohmic contact electrode in the step (e) is formed on an upper surface of a buffering layer or an n-type semiconductor cladding layer. 
     
     
         24 . The method for preparing a semiconductor light-emitting device of  claim 11 , wherein the supporting substrate for preparing a semiconductor light-emitting device of the second wafer is the supporting substrate for preparing a semiconductor light-emitting device according to  claim 1 . 
     
     
         25 . The method for preparing a semiconductor light-emitting device of  claim 12 , wherein each layer of the semiconductor multi-layered light-emitting structure in the step (a) is composed of a single crystal of In x (Ga y Al 1-y )N(1=x=0, 1=y=0, x+y>0). 
     
     
         26 . The method for preparing a semiconductor light-emitting device of  claim 12 , wherein the separating of the initial substrate of the first wafer from the bonded result in the step (d) is performed by a method selected from the group consisting of a laser lift-off method irradiating a laser beam to a surface of the initial substrate, a chemo-mechanical polishing method, and a wet etching method using a wet etching solution.