A light emitting diode chip and a method of manufacturing the same

Abstract

The application provides a light emitting diode and a manufacturing method thereof. An insertion layer is arranged between a metal reflection layer and a dielectric film layer. The adhesion between the material of the insertion layer and the material of the dielectric film layer is greater than the adhesion between the material of the metal reflection layer and the material of the dielectric film layer. The adhesion between the metal reflection layer and the dielectric film layer is improved through the insertion layer. The separation between the metal reflection layer and the dielectric film layer is improved. The reliability of the light emitting diode is improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor device technology, and more specifically, to a light-emitting diode and a method for manufacturing the same. Background Technology

[0002] With the development of LED technology, LEDs are now widely used in electronics, optics, and other fields, and have made significant strides in lighting, displays, and digital applications. Furthermore, as the applications of LEDs expand, market demands for their performance are increasing. Therefore, the reliability of current LEDs needs further improvement. Summary of the Invention

[0003] In view of this, the present invention provides a light-emitting diode and a method for manufacturing the same, which effectively solves the technical problems existing in the prior art and improves the reliability of the light-emitting diode.

[0004] To achieve the above objectives, the technical solution provided by the present invention is as follows:

[0005] A light-emitting diode chip, comprising:

[0006] Back electrode;

[0007] A conductive substrate located on one side of the back electrode;

[0008] A metal bonding layer located on the side of the conductive substrate opposite to the back electrode;

[0009] An ODR reflector layer is located on the side of the metal bonding layer opposite to the back electrode. The ODR reflector layer includes a metal reflective layer, an insertion layer located on the side of the metal reflective layer opposite to the back electrode, and a dielectric film layer located on the side of the insertion layer opposite to the back electrode. The ODR reflector layer includes a plurality of through holes that transmit through the stack of the dielectric film layer and the insertion layer, and the adhesion between the material of the insertion layer and the material of the dielectric film layer is greater than the adhesion between the material of the metal reflective layer and the material of the dielectric film layer.

[0010] Contact electrodes filling the through-hole;

[0011] An epitaxial layer located on the side of the ODR mirror layer opposite to the back electrode, the epitaxial layer including a P-type window layer facing the back electrode side, the P-type window layer being in contact with the contact electrode;

[0012] And a positive electrode located on the side of the epitaxial layer opposite to the back electrode.

[0013] Optionally, the contact electrode includes an ohmic contact layer and a diffusion barrier layer located on the side of the ohmic contact layer opposite to the back electrode.

[0014] Optionally, the ohmic contact layer is an AuZn layer;

[0015] The diffusion barrier layer is an ITO layer or a Ni layer.

[0016] Optionally, the insert layer is an Al2O3 layer.

[0017] Optionally, the exposed surface of the epitaxial layer on the side opposite to the back electrode is a roughened surface.

[0018] Optionally, the epitaxial layer includes the P-type window layer;

[0019] A P-type confinement layer located on the side of the P-type window layer opposite to the back electrode;

[0020] An active layer located on the side of the P-type confinement layer opposite to the back electrode;

[0021] An N-type confinement layer located on the side of the active layer opposite to the back electrode;

[0022] An N-type current spreading layer located on the side of the N-type confinement layer opposite to the back electrode;

[0023] An N-type roughening layer located on the side of the N-type current extension layer opposite to the back electrode;

[0024] and an N-type ohmic contact layer located on the side of the N-type roughened layer away from the back electrode, wherein the positive electrode is located on the side of the N-type ohmic contact layer away from the back electrode.

[0025] Optionally, in the direction from the back electrode to the positive electrode, the N-type roughening layer includes a first sub-layer to the Mth sub-layer stacked sequentially, and the Al composition of the i-th sub-layer is less than the Al composition of the (i+1)-th sub-layer, where M is an integer greater than or equal to 2, and i is an integer greater than or equal to 1 and less than M.

[0026] Alternatively, in the direction from the back electrode to the positive electrode, the N-type roughening layer includes alternating gradient sublayers and constant sublayers, wherein in any two adjacent gradient sublayers, the Al composition in the gradient sublayer closer to the back electrode is less than the Al composition in the gradient sublayer farther from the back electrode, and the Al composition in all the constant sublayers is the same.

[0027] Alternatively, in the direction from the back electrode to the positive electrode, the N-type roughening layer includes sequentially stacked first sublayers to Kth sublayers, and the Al composition of the Kth sublayer is greater than the Al composition of the other sublayers, where K is an integer greater than or equal to 2.

[0028] Accordingly, the present invention also provides a method for manufacturing a light-emitting diode chip, comprising:

[0029] A buffer layer, an etching stop layer, and an epitaxial layer are sequentially grown on a temporary substrate, wherein the epitaxial layer has a P-type window layer on the side facing away from the temporary substrate.

[0030] An ODR mirror layer is formed on the side of the P-type window layer away from the temporary substrate. The ODR mirror layer includes a metal reflective layer, an insertion layer located on the side of the metal reflective layer facing the epitaxial layer, and a dielectric film layer located on the side of the insertion layer facing the epitaxial layer. The ODR mirror layer includes a plurality of through-holes that transmit through the stack of the dielectric film layer and the insertion layer. The through-holes are filled with contact electrodes. The adhesion between the material of the insertion layer and the material of the dielectric film layer is greater than the adhesion between the material of the metal reflective layer and the material of the dielectric film layer.

[0031] A first sub-metal bonding layer is formed on the side of the ODR reflector layer away from the temporary substrate, and a second sub-metal bonding layer is formed on the side of the conductive substrate. The first sub-metal bonding layer and the second sub-metal bonding layer are then bonded together to form a metal bonding layer.

[0032] Remove the temporary substrate, buffer layer, and etch stop layer;

[0033] A positive electrode is formed on the side of the epitaxial layer away from the conductive substrate, and a back electrode is formed on the side of the conductive substrate away from the epitaxial layer.

[0034] Optionally, the contact electrode includes an ohmic contact layer and a diffusion barrier layer located on the side of the ohmic contact layer opposite to the back electrode.

[0035] Optionally, the exposed surface of the epitaxial layer on the side opposite to the back electrode is a roughened surface.

[0036] Compared with the prior art, the technical solution provided by the present invention has at least the following advantages:

[0037] This invention provides a light-emitting diode and a method for fabricating the same, comprising: a back electrode; a conductive substrate located on one side of the back electrode; a metal bonding layer located on the conductive substrate away from the back electrode; an ODR (Optical Displacement Reflector) mirror layer located on the metal bonding layer away from the back electrode, the ODR mirror layer comprising a metal reflective layer, an insertion layer located on the metal reflective layer away from the back electrode, and a dielectric film layer located on the insertion layer away from the back electrode, wherein the ODR mirror layer comprises a plurality of through-holes that transmit through the stack of the dielectric film layer and the insertion layer, and the adhesion between the material of the insertion layer and the material of the dielectric film layer is greater than the adhesion between the material of the metal reflective layer and the material of the dielectric film layer; a contact electrode filled in the through-holes; an epitaxial layer located on the ODR mirror layer away from the back electrode, the epitaxial layer comprising a P-type window layer facing the back electrode, the P-type window layer being in contact with the contact electrode; and a positive electrode located on the epitaxial layer away from the back electrode.

[0038] As can be seen from the above, the technical solution provided by the present invention includes an insertion layer between the metal reflective layer and the dielectric film layer, and the adhesion between the material of the insertion layer and the material of the dielectric film layer is greater than the adhesion between the material of the metal reflective layer and the material of the dielectric film layer. In this way, the adhesion between the metal reflective layer and the dielectric film layer can be improved by the insertion layer, the separation between the metal reflective layer and the dielectric film layer can be improved, and the reliability of the light-emitting diode can be improved. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0040] Figure 1 A structural diagram of a light-emitting diode chip provided in an embodiment of the present invention;

[0041] Figure 2 This is a structural diagram of another light-emitting diode chip provided in an embodiment of the present invention;

[0042] Figure 3 This is a structural diagram of another light-emitting diode chip provided in an embodiment of the present invention;

[0043] Figure 4 This is a structural diagram of another light-emitting diode chip provided in an embodiment of the present invention;

[0044] Figure 5A flowchart illustrating a method for fabricating a light-emitting diode chip according to an embodiment of the present invention. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] As described in the background section, with the development of LED technology, existing LEDs are widely used in electronics, optics, and other fields, and have made significant progress in lighting, displays, and digital applications. Furthermore, as the applications of LEDs gradually expand, the market demands higher and higher performance from LEDs. Therefore, the reliability of current LEDs needs to be improved.

[0047] Based on this, embodiments of the present invention provide a light-emitting diode and a method for manufacturing the same, effectively solving the technical problems existing in the prior art and improving the reliability of the light-emitting diode.

[0048] To achieve the above objectives, the technical solutions provided by the embodiments of the present invention are as follows, in detail... Figures 1 to 5 The technical solutions provided in the embodiments of the present invention will be described in detail.

[0049] refer to Figure 1 The diagram shown is a structural schematic of a light-emitting diode (LED) chip provided in an embodiment of the present invention. The LED chip includes:

[0050] Back electrode 100.

[0051] A conductive substrate 200 located on one side of the back electrode 100.

[0052] A metal bonding layer 300 located on the side of the conductive substrate 200 opposite to the back electrode 100.

[0053] An ODR reflector layer is located on the side of the metal bonding layer 300 facing away from the back electrode 100. The ODR reflector layer includes a metal reflective layer 410, an insertion layer 420 located on the side of the metal reflective layer 410 facing away from the back electrode 100, and a dielectric film layer 430 located on the side of the insertion layer 420 facing away from the back electrode 100. The ODR reflector layer includes a plurality of through holes that allow the dielectric film layer 430 and the insertion layer 420 to pass through the stack. The adhesion between the material of the insertion layer 420 and the material of the dielectric film layer 430 is greater than the adhesion between the material of the metal reflective layer 410 and the material of the dielectric film layer 430.

[0054] Contact electrode 440 filling the through hole.

[0055] An epitaxial layer 500 is located on the side of the ODR mirror layer opposite to the back electrode 100. The epitaxial layer includes a P-type window layer 510 facing the back electrode 100. The P-type window layer 510 is in contact with the contact electrode 440.

[0056] and a positive electrode 600 located on the side of the epitaxial layer 500 away from the back electrode 100, wherein the area occupied by the positive electrode 600 is smaller than the area of ​​the surface of the epitaxial layer 500 on the side away from the back electrode 100.

[0057] In one embodiment of the present invention, the metal reflective layer provided by the present invention can be an Ag reflective layer. The dielectric film layer can be a SiO2 film layer or a MgF2 film layer. Furthermore, the insertion layer provided by the present invention can be an Al2O3 layer.

[0058] As can be seen from the above, the technical solution provided by the embodiments of the present invention includes an insertion layer between the metal reflective layer and the dielectric film layer, and the adhesion between the material of the insertion layer and the material of the dielectric film layer is greater than the adhesion between the material of the metal reflective layer and the material of the dielectric film layer. In this way, the adhesion between the metal reflective layer and the dielectric film layer can be improved by the insertion layer, the separation between the metal reflective layer and the dielectric film layer can be improved, and the reliability of the light-emitting diode can be improved.

[0059] In one embodiment of the present invention, the contact electrode of the light-emitting diode chip provided by the present invention can be composed of an ohmic contact layer and a diffusion barrier layer. The diffusion barrier layer can prevent metal atoms of the ohmic contact layer from diffusing into the epitaxial layer, thereby avoiding problems that affect the performance of the light-emitting diode chip. Figure 2 The diagram shown is a structural schematic of another light-emitting diode (LED) chip provided in an embodiment of the present invention, wherein the LED chip includes:

[0060] Back electrode 100.

[0061] A conductive substrate 200 located on one side of the back electrode 100.

[0062] A metal bonding layer 300 located on the side of the conductive substrate 200 opposite to the back electrode 100.

[0063] An ODR reflector layer is located on the side of the metal bonding layer 300 facing away from the back electrode 100. The ODR reflector layer includes a metal reflective layer 410, an insertion layer 420 located on the side of the metal reflective layer 410 facing away from the back electrode 100, and a dielectric film layer 430 located on the side of the insertion layer 420 facing away from the back electrode 100. The ODR reflector layer includes a plurality of through holes that allow the dielectric film layer 430 and the insertion layer 420 to pass through the stack. The adhesion between the material of the insertion layer 420 and the material of the dielectric film layer 430 is greater than the adhesion between the material of the metal reflective layer 410 and the material of the dielectric film layer 430.

[0064] A contact electrode 440 is filled within the through-hole. The contact electrode 440 includes an ohmic contact layer 441 and a diffusion barrier layer 442 located on the side of the ohmic contact layer 441 opposite to the back electrode 100.

[0065] An epitaxial layer 500 is located on the side of the ODR mirror layer opposite to the back electrode 100. The epitaxial layer includes a P-type window layer 510 facing the back electrode 100. The P-type window layer 510 is in contact with the contact electrode 440.

[0066] and a positive electrode 600 located on the side of the epitaxial layer 500 away from the back electrode 100, wherein the area occupied by the positive electrode 600 is smaller than the area of ​​the surface of the epitaxial layer 500 on the side away from the back electrode 100.

[0067] In one embodiment of the present invention, the ohmic contact layer provided by the present invention is an AuZn layer; and the diffusion barrier layer is an ITO layer or a Ni layer. Furthermore, the diffusion barrier layer can prevent Zn atoms from diffusing into the epitaxial layer.

[0068] Understandably, in the technical solution provided by the embodiments of the present invention, after forming a via in the stack of dielectric film layer and insertion layer, a low-temperature ultrathin ITO layer or Ni layer can be first deposited as a diffusion barrier layer to contact the P-type window layer, and then an AuZn layer can be deposited as a P-type ohmic contact layer to fill the via, so that it can be connected to the ohmic contact layer when the metal reflective layer is subsequently fabricated, thereby realizing the ohmic contact between the metal reflective layer and the P-type window layer.

[0069] In one embodiment of the present invention, in order to improve the light emission brightness of the light-emitting diode chip, the exposed surface of the epitaxial layer on the side away from the back electrode provided in this embodiment of the present invention is roughened. For example... Figure 3 The diagram shown is a structural schematic of another light-emitting diode (LED) chip provided in an embodiment of the present invention, wherein the LED chip includes:

[0070] Back electrode 100.

[0071] A conductive substrate 200 located on one side of the back electrode 100.

[0072] A metal bonding layer 300 located on the side of the conductive substrate 200 opposite to the back electrode 100.

[0073] An ODR reflector layer is located on the side of the metal bonding layer 300 facing away from the back electrode 100. The ODR reflector layer includes a metal reflective layer 410, an insertion layer 420 located on the side of the metal reflective layer 410 facing away from the back electrode 100, and a dielectric film layer 430 located on the side of the insertion layer 420 facing away from the back electrode 100. The ODR reflector layer includes a plurality of through holes that allow the dielectric film layer 430 and the insertion layer 420 to pass through the stack. The adhesion between the material of the insertion layer 420 and the material of the dielectric film layer 430 is greater than the adhesion between the material of the metal reflective layer 410 and the material of the dielectric film layer 430.

[0074] A contact electrode 440 is filled within the through-hole. Optionally, the contact electrode 440 provided in this embodiment of the invention includes an ohmic contact layer 441 and a diffusion barrier layer 442 located on the side of the ohmic contact layer 441 opposite to the back electrode 100.

[0075] An epitaxial layer 500 is located on the side of the ODR mirror layer facing away from the back electrode 100. The epitaxial layer includes a P-type window layer 510 facing the back electrode 100, and the P-type window layer 510 is in contact with the contact electrode 440. The exposed surface of the epitaxial layer 500 on the side facing away from the back electrode 100 is a roughened surface.

[0076] and a positive electrode 600 located on the side of the epitaxial layer 500 away from the back electrode 100, wherein the area occupied by the positive electrode 600 is smaller than the area of ​​the surface of the epitaxial layer 500 on the side away from the back electrode 100.

[0077] like Figure 4 The diagram shown is a structural schematic of another light-emitting diode chip provided in an embodiment of the present invention, wherein the epitaxial layer of the light-emitting diode chip includes the P-type window layer 510.

[0078] A P-type confinement layer 520 located on the side of the P-type window layer 510 opposite to the back electrode 100.

[0079] The active layer 530 is located on the side of the P-type confinement layer 520 opposite to the back electrode 100.

[0080] An N-type confinement layer 540 is located on the side of the active layer 530 opposite to the back electrode 100.

[0081] An N-type current spreading layer 550 is located on the side of the N-type confinement layer 540 opposite to the back electrode 100.

[0082] An N-type roughening layer 560 is located on the side of the N-type current extension layer 550 away from the back electrode 100, wherein the exposed surface of the N-type roughening layer 560 on the side away from the back electrode 100 is connected to the roughened surface.

[0083] An N-type ohmic contact layer 570 is located on the side of the N-type roughened layer 560 opposite to the back electrode 100, and the positive electrode 600 is located on the side of the N-type ohmic contact layer 570 opposite to the back electrode 100. The N-type ohmic contact layer 570 can be a patterned ohmic contact layer, and this invention does not impose specific limitations on it.

[0084] In one embodiment of the present invention, the light-emitting diode chip provided by the present invention can be a vertical thin-film chip structure based on AlGaInP. Specifically, the P-type window layer provided in this embodiment can be a P-type GaP window layer, the P-type confinement layer can be a P-type AlGaInP confinement layer, the active layer can be an MQW light-emitting layer, the N-type confinement layer can be an N-type AlGaInP confinement layer, the N-type current spreading layer can be an N-type AlGaInP current spreading layer, the N-type roughening layer can be an N-type AlGaInP roughening layer, and the N-type ohmic contact layer can be an N-type GaAs ohmic contact layer.

[0085] Furthermore, the thickness of the P-type window layer provided in this embodiment of the invention can be 0.1-10 μm, including the endpoint values; optimizedly, the thickness of the P-type window layer provided in this embodiment of the invention can be 1-3 μm, including the endpoint values. The doping concentration of the surface layer of the P-type GaP window layer on the side away from the positive electrode can be [value missing], and the doping concentration of the remaining main body of the P-type GaP window layer can be not less than 1E18 / cm3, which is not specifically limited in this invention.

[0086] Furthermore, to improve the fluctuation problem of the roughening depth of the roughened surface of the epitaxial layer, the present invention can optimize the composition of the roughened layer. Optionally, when the composition of the N-type roughened layer includes Al, the Al composition in the N-type roughened layer can vary from low to high in the direction from the back electrode to the positive electrode, or it can be configured in other ways. Specifically, in the direction from the back electrode to the positive electrode, the N-type roughened layer includes a first sub-layer to an M-th sub-layer stacked sequentially, that is, the first sub-layer is close to the back electrode, while the M-th sub-layer is far from the back electrode, and the Al composition of the i-th sub-layer is less than the Al composition of the (i+1)-th sub-layer, where M is an integer greater than or equal to 2, and i is an integer greater than or equal to 1 and less than M.

[0087] Alternatively, in the direction from the back electrode to the positive electrode, the N-type roughening layer includes alternating gradient sublayers and constant sublayers. In any two adjacent gradient sublayers, the Al composition in the gradient sublayer closer to the back electrode is less than the Al composition in the gradient sublayer farther from the back electrode, and the Al composition in all the constant sublayers is the same. Optionally, the last alternating layer can be a gradient sublayer, and the Al composition of the gradient sublayer in the last layer can be greater than the Al composition of the constant sublayer.

[0088] Alternatively, in the direction from the back electrode to the positive electrode, the N-type roughening layer includes a first sublayer to a Kth sublayer stacked sequentially, i.e., the first sublayer is close to the back electrode, while the Kth sublayer is far from the back electrode, and the Al composition of the Kth sublayer is greater than the Al composition of the other sublayers, where K is an integer greater than or equal to 2.

[0089] Understandably, in the N-type roughening layer, the higher the Al content, the faster the roughening reaction rate, which can easily lead to excessive roughening. Conversely, the lower the Al content, the slower the roughening reaction rate. Therefore, setting the N-type roughening layer to a compositional gradient can regulate the roughening depth, effectively control the roughening depth, and solve the problem of large fluctuations in roughening depth during the manufacturing process.

[0090] This invention also provides a method for manufacturing a light-emitting diode (LED) chip, used to manufacture the LED chip provided in any of the above embodiments. (See reference) Figure 5 The diagram shows a flowchart of a method for manufacturing a light-emitting diode (LED) chip according to an embodiment of the present invention. The manufacturing method includes:

[0091] S1. A buffer layer, an etching stop layer, and an epitaxial layer are sequentially grown on a temporary substrate. The epitaxial layer on the side facing away from the temporary substrate is a P-type window layer.

[0092] In one embodiment of the present invention, the temporary substrate provided by the present invention can be a GaAs temporary substrate, the buffer layer can be an N-type GaAs buffer layer, and the etching stop layer can be an N-type GaInP etching stop layer. The epitaxial layer can be an AlGaInP-based epitaxial layer or an AlGaAs-based epitaxial layer; the present invention does not impose specific limitations on this.

[0093] S2. An ODR mirror layer is formed on the side of the P-type window layer away from the temporary substrate. The ODR mirror layer includes a metal reflective layer, an insertion layer located on the side of the metal reflective layer facing the epitaxial layer, and a dielectric film layer located on the side of the insertion layer facing the epitaxial layer. The ODR mirror layer includes a plurality of through holes that transmit through the stack of the dielectric film layer and the insertion layer. The through holes are filled with contact electrodes. The adhesion between the material of the insertion layer and the material of the dielectric film layer is greater than the adhesion between the material of the metal reflective layer and the material of the dielectric film layer.

[0094] In one embodiment of the present invention, the contact electrode provided by the present invention includes an ohmic contact layer and a diffusion barrier layer located on the side of the ohmic contact layer opposite to the back electrode.

[0095] In one embodiment of the present invention, when fabricating the ODR mirror layer, a dielectric film layer and an insertion layer are first deposited sequentially on the P-type window layer away from the temporary substrate; then, a through-hole is formed in the stack of the dielectric film layer and the insertion layer using photolithography; then, a diffusion barrier layer and an ohmic contact layer are sequentially deposited in the through-hole, which can be prepared using a lift-off photolithography process; finally, a metal reflective layer is formed on the side of the insertion layer away from the dielectric film layer, and after annealing to form an ohmic contact between the metal reflective layer and the ohmic contact layer, the fabrication of the ODR mirror layer is completed.

[0096] In one embodiment of the present invention, the thickness of the dielectric film provided by the present invention can be obtained according to (2k+1)λ / 4n, where k is 0 or a positive integer, λ is the light emission wavelength of the light-emitting diode, and n is the refractive index of the dielectric film material. Taking the SiO2 dielectric film as an example, taking k=1, for red light with a wavelength of λ=630nm, the refractive index of SiO2 is n=1.45, and the initial thickness of the SiO2 dielectric film is calculated to be 3258 angstroms. Further, taking Al2O3 as an example for the insertion layer, the refractive index of Al2O3 is n=1.77, and the optical path of a 100 angstrom thick Al2O3 insertion layer is equivalent to that of a 122 angstrom thick SiO2 dielectric film. Therefore, the final thickness of the SiO2 dielectric film is corrected to 3258 angstroms - 122 angstroms = 3136 angstroms.

[0097] S3. A first sub-metal bonding layer is formed on the side of the ODR reflector layer away from the temporary substrate, and a second sub-metal bonding layer is formed on the side of the conductive substrate. The first sub-metal bonding layer and the second sub-metal bonding layer are bonded together to form a metal bonding layer.

[0098] In one embodiment of the present invention, the present invention can use a hot pressing process to bond the first sub-metal bonding layer and the second sub-metal bonding layer to obtain a metal bonding layer, thereby fixing the epitaxial layer and the conductive substrate.

[0099] Optionally, the conductive substrate provided in the embodiments of the present invention can be a P-type low-resistivity silicon wafer substrate, and the present invention does not impose specific limitations on it.

[0100] S4. Remove the temporary substrate, buffer layer and corrosion stop layer.

[0101] S5. A positive electrode is formed on the side of the epitaxial layer away from the conductive substrate, and a back electrode is formed on the side of the conductive substrate away from the epitaxial layer.

[0102] In one embodiment of the present invention, the N-type ohmic contact layer can be patterned to form an N-type ohmic contact pattern, and then an N-type electrode, i.e. a positive electrode, can be prepared by subsequent photolithography, vapor deposition, lift-off and annealing processes.

[0103] In one embodiment of the present invention, the exposed surface of the epitaxial layer on the side away from the back electrode is a roughened surface, which can improve the light output brightness of the light-emitting diode chip.

[0104] Optionally, after forming the positive electrode on the conductive substrate, if it is necessary to cleave the wafer source, the reserved cutting path can be etched to the P-type window layer by photolithography or dry etching process; then, the exposed surface of the epitaxial layer can be roughened to form a roughened surface, and the N-type roughened layer can be roughened; then, the conductive substrate can be thinned by grinding, and the P-type electrode can be prepared by lattice evaporation annealing process, that is, the back electrode can be prepared; finally, the wafer source can be divided into independent light-emitting diode chips by slicing, back-slicing and cleaving processes, which is the same as the prior art, so the present invention will not elaborate further.

[0105] This invention provides a light-emitting diode and a method for fabricating the same, comprising: a back electrode; a conductive substrate located on one side of the back electrode; a metal bonding layer located on the conductive substrate away from the back electrode; an ODR (Optical Displacement Reflector) mirror layer located on the metal bonding layer away from the back electrode, the ODR mirror layer comprising a metal reflective layer, an insertion layer located on the metal reflective layer away from the back electrode, and a dielectric film layer located on the insertion layer away from the back electrode, wherein the ODR mirror layer comprises a plurality of through-holes that transmit through the stack of the dielectric film layer and the insertion layer, and the adhesion between the material of the insertion layer and the material of the dielectric film layer is greater than the adhesion between the material of the metal reflective layer and the material of the dielectric film layer; a contact electrode filled in the through-holes; an epitaxial layer located on the ODR mirror layer away from the back electrode, the epitaxial layer comprising a P-type window layer facing the back electrode, the P-type window layer being in contact with the contact electrode; and a positive electrode located on the epitaxial layer away from the back electrode.

[0106] As can be seen from the above, the technical solution provided by the embodiments of the present invention includes an insertion layer between the metal reflective layer and the dielectric film layer, and the adhesion between the material of the insertion layer and the material of the dielectric film layer is greater than the adhesion between the material of the metal reflective layer and the material of the dielectric film layer. In this way, the adhesion between the metal reflective layer and the dielectric film layer can be improved by the insertion layer, the separation between the metal reflective layer and the dielectric film layer can be improved, and the reliability of the light-emitting diode can be improved.

[0107] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A light-emitting diode chip, characterized in that, include: Back electrode; A conductive substrate located on one side of the back electrode; A metal bonding layer located on the side of the conductive substrate opposite to the back electrode; An ODR reflector layer is located on the side of the metal bonding layer opposite to the back electrode. The ODR reflector layer includes a metal reflective layer, an insertion layer located on the side of the metal reflective layer opposite to the back electrode, and a dielectric film layer located on the side of the insertion layer opposite to the back electrode. The ODR reflector layer includes a plurality of through holes that transmit through the stack of the dielectric film layer and the insertion layer, and the adhesion between the material of the insertion layer and the material of the dielectric film layer is greater than the adhesion between the material of the metal reflective layer and the material of the dielectric film layer. Contact electrodes filling the through-hole; An epitaxial layer located on the side of the ODR mirror layer opposite to the back electrode, the epitaxial layer including a P-type window layer facing the back electrode side, the P-type window layer being in contact with the contact electrode; And a positive electrode located on the side of the epitaxial layer opposite to the back electrode.

2. The light-emitting diode chip according to claim 1, characterized in that, The contact electrode includes an ohmic contact layer and a diffusion barrier layer located on the side of the ohmic contact layer opposite to the back electrode.

3. The light-emitting diode chip according to claim 2, characterized in that, The ohmic contact layer is an AuZn layer; The diffusion barrier layer is an ITO layer or a Ni layer.

4. The light-emitting diode chip according to claim 1, characterized in that, The inserted layer is an Al2O3 layer.

5. The light-emitting diode chip according to claim 1, characterized in that, The exposed surface of the epitaxial layer on the side opposite to the back electrode is a roughened surface.

6. The light-emitting diode chip according to any one of claims 1-5, characterized in that, The epitaxial layer includes the P-type window layer; A P-type confinement layer located on the side of the P-type window layer opposite to the back electrode; An active layer located on the side of the P-type confinement layer opposite to the back electrode; An N-type confinement layer located on the side of the active layer opposite to the back electrode; An N-type current spreading layer located on the side of the N-type confinement layer opposite to the back electrode; An N-type roughening layer located on the side of the N-type current extension layer opposite to the back electrode; and an N-type ohmic contact layer located on the side of the N-type roughened layer away from the back electrode, wherein the positive electrode is located on the side of the N-type ohmic contact layer away from the back electrode.

7. The light-emitting diode chip according to claim 6, characterized in that, From the back electrode to the positive electrode, the N-type roughening layer includes a first sub-layer to the Mth sub-layer stacked sequentially, and the Al composition of the i-th sub-layer is less than the Al composition of the (i+1)-th sub-layer, where M is an integer greater than or equal to 2, and i is an integer greater than or equal to 1 and less than M. Alternatively, in the direction from the back electrode to the positive electrode, the N-type roughening layer includes alternating gradient sublayers and constant sublayers, wherein in any two adjacent gradient sublayers, the Al composition in the gradient sublayer closer to the back electrode is less than the Al composition in the gradient sublayer farther from the back electrode, and the Al composition in all the constant sublayers is the same. Alternatively, in the direction from the back electrode to the positive electrode, the N-type roughening layer includes sequentially stacked first sublayers to Kth sublayers, and the Al composition of the Kth sublayer is greater than the Al composition of the other sublayers, where K is an integer greater than or equal to 2.

8. A method for manufacturing a light-emitting diode chip, characterized in that, include: A buffer layer, an etching stop layer, and an epitaxial layer are sequentially grown on a temporary substrate, wherein the epitaxial layer has a P-type window layer on the side facing away from the temporary substrate. An ODR mirror layer is formed on the side of the P-type window layer away from the temporary substrate. The ODR mirror layer includes a metal reflective layer, an insertion layer located on the side of the metal reflective layer facing the epitaxial layer, and a dielectric film layer located on the side of the insertion layer facing the epitaxial layer. The ODR mirror layer includes a plurality of through-holes that transmit through the stack of the dielectric film layer and the insertion layer. The through-holes are filled with contact electrodes. The adhesion between the material of the insertion layer and the material of the dielectric film layer is greater than the adhesion between the material of the metal reflective layer and the material of the dielectric film layer. A first sub-metal bonding layer is formed on the side of the ODR reflector layer away from the temporary substrate, and a second sub-metal bonding layer is formed on the side of the conductive substrate. The first sub-metal bonding layer and the second sub-metal bonding layer are then bonded together to form a metal bonding layer. Remove the temporary substrate, buffer layer, and etch stop layer; A positive electrode is formed on the side of the epitaxial layer away from the conductive substrate, and a back electrode is formed on the side of the conductive substrate away from the epitaxial layer.

9. The method for manufacturing a light-emitting diode chip according to claim 8, characterized in that, The contact electrode includes an ohmic contact layer and a diffusion barrier layer located on the side of the ohmic contact layer opposite to the back electrode.

10. The method for manufacturing a light-emitting diode chip according to claim 8, characterized in that, The exposed surface of the epitaxial layer on the side opposite to the back electrode is a roughened surface.

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