JPH10335699A - Compound semiconductor light emitting element and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode to the upside and underside of a compound semiconductor light emitting element on an insulating substrate. SOLUTION: A semiconductor light emitting element 15 is formed through such a manner that light emitting parts are each formed on a semiconductor substrate 100 as demarcated with a shallow groove and divided into unit light emitting elements along the shallow grooves by a dicer. In this case, upper and lower grooves (lower groove 220) are provided in the substrate 100, through- holes are each provided in the intersection of the grooves, and a thin film electrode wiring 170 is formed on the lower side of the compound semiconductor thin film layer 101 as a light emitting part extending onto the side of the substrate 100, taking advantage of the through-holes. At the same time or almost simultaneously, a first electrode 105 is formed on the upside of the upper compound semiconductor thin film layer, a second electrode 160 is formed on the underside of the substrate 100, and the second electrode 160 and the thin film electrode wiring 170 are electrically connected together.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a compound semiconductor light emitting device, particularly to a light emitting diode, a semiconductor laser and a method for manufacturing the same.

[0002]

2. Description of the Related Art A general method of manufacturing and inspecting a conventional general chip-shaped compound semiconductor light-emitting device (hereinafter abbreviated as "device") is as follows. First, for example, a negative electrode is provided on the entire back surface of a substrate with a compound semiconductor thin film layer in which a predetermined semiconductor thin film layer is laminated on a substantially disk-shaped semiconductor substrate. Next, a plurality of positive electrodes are provided on the surface of the substrate with the compound semiconductor thin film layer in a state where predetermined gaps are regularly formed. Next, using an etching method or the like, from the surface side of the substrate with the compound semiconductor thin film layer to the gap between the positive electrodes,
Grooves are formed vertically and horizontally deeper than the semiconductor thin film layer. At this stage, the positive electrode side of the surface of the substrate with the compound semiconductor thin film layer is formed so as to function as a plurality of light emitting portions (and one positive electrode is usually provided for one light emitting portion). State). Then, at this stage, the light emitting unit is inspected.

[0003] A schematic configuration of an inspection apparatus is composed of a power supply unit for generating a predetermined inspection voltage, two electrode units (one is a needle-like electrode unit) extending from the power supply unit, and a needle-like electrode unit. A needle-like electrode unit moving unit that moves at predetermined intervals (positioned on a predetermined electrode) and a light receiving unit that measures the amount of light emitted from the light emitting unit on the substrate with the compound semiconductor thin film layer to be inspected Consists of Using the inspection device, an electrode portion on one end side (zero volt, that is, ground) of a predetermined voltage for inspection is connected to a negative electrode formed on the entire back surface of the substrate with a compound semiconductor thin film layer. The other electrode (needle-shaped electrode)
Is brought into contact with the positive electrode on the light emitting section. Therefore,
Since a predetermined inspection voltage is applied between the positive electrode and the negative electrode, only one light emitting unit to which this voltage is applied emits light. The light receiving unit of the inspection device is positioned above the light emitting unit that emits light, and the light emission amount is measured. This operation is performed for each of the plurality of light emitting units.

After this inspection, a groove is dug along the already formed groove using a dicer (a device for cutting or kerfing), and the light emitting portions are completely cut off. Device. After this, each element is usually wire-bonded and sealed with a resin mold or a can package or the like to obtain a completed product.

However, in a compound semiconductor light emitting device (hereinafter, abbreviated as “device”) such as a blue LED, for example, an insulating substrate (such as a sapphire substrate) is used, and a compound semiconductor thin film layer is laminated on the substrate. This is the stage of the substrate with a compound semiconductor thin film layer described above. Therefore, since the back side of the substrate with a compound semiconductor thin film layer as described above is not a conductive semiconductor substrate but an insulating substrate, it is necessary to provide electrodes only on the entire back side of the substrate with a compound semiconductor thin film layer. It does not mean that the wiring was performed.

For this reason, the following electrode forming structures and manufacturing methods have been adopted for devices such as blue LEDs.

The following structures are available as electrode formation structures. A structure in which a positive electrode and a negative electrode are formed on one surface (surface) of the element [see Japanese Patent Application Laid-Open No. 7-94782]. A structure in which a positive electrode is formed on the front surface of the device and a negative electrode is formed on the back surface.

The following structures (A), (B) and (C) are known or easily considered as a manufacturing method for this structure.
In order to simplify the explanation, the layer formed on the uppermost surface on the front side of the substrate with a compound semiconductor thin film layer is a P-type semiconductor layer, and there is an N-type semiconductor layer under the P-type semiconductor layer, It is assumed that an insulating substrate is provided below the N-type semiconductor layer (therefore, an electrode provided on the front side of the substrate with a compound semiconductor thin film layer is a positive electrode, and an electrode provided on the back side of the substrate with a compound semiconductor thin film layer is a negative electrode). Electrodes).

Method (A): After providing a positive electrode and a negative electrode on the front side and the back side of the substrate with a compound semiconductor thin film layer, respectively, the substrate with the compound semiconductor thin film layer is diced at a stroke until the element stage with a dicer. Cut into pieces. Thereafter, wiring is performed for each element from the N-type semiconductor layer to the negative electrode (that is, at this stage, the N-type semiconductor layer, the wiring, and the negative electrode on the back side of the substrate with the compound semiconductor thin film layer are mutually connected). Electrically connected).

Method (B): After providing a positive electrode and a negative electrode on the front and back sides of the substrate with a compound semiconductor thin-film layer, respectively, dicing the grooves vertically and horizontally from the upper surface of the substrate with the compound semiconductor thin-film layer with a dicer. (That is, the groove is cut from the upper surface of the substrate with the compound semiconductor thin film layer to about half the thickness of the substrate with the compound semiconductor thin film layer). Therefore, a plurality of light emitting portions are formed on the upper surface of the substrate with the compound semiconductor thin film layer. Through holes are provided by etching in the grooves around each light emitting unit and on each light emitting unit side. A wiring is formed in the through hole from the N-type semiconductor layer to the negative electrode. Thereafter, a groove smaller than the groove is dug by a dicer along the center line of the groove so as to avoid this wiring, and the light emitting portions are completely cut to separate into a plurality of elements. Even at this stage, since the wiring remains, the N-type semiconductor layer, the wiring, and the negative electrode on the back side of the substrate with the compound semiconductor thin film layer are electrically connected to each other.

Method (C): As disclosed in JP-A-7-221347, only the insulating substrate is removed from the back side of the substrate with the compound semiconductor thin film layer by etching or the like, and the exposed N-type semiconductor is removed. A negative electrode is formed on the layer.

[0012]

In the conventional method, there are a number of problems as described below as compared with a device in which electrodes are provided on both sides of the device.

Since the positive electrode and the negative electrode are provided on one side of the element, it is necessary to increase the distance between the two electrodes so that the wires connected to the two electrodes do not come into contact with each other.
The size of the element becomes large. In addition, the area of the PN junction is reduced, the area of the electrode is widely occupied on the light emitting surface side, and one wire is added on the light emitting surface side. From this point, it is necessary to increase the area of the element in order to secure a predetermined light emission amount. Therefore, the utilization efficiency of the substrate with a compound semiconductor thin film layer is poor. That is, the number of elements that can be obtained from one substrate with a compound semiconductor thin film layer is reduced, which is a bottleneck in cost reduction.

At the stage of inspection, a conventional inspection device cannot be used. For this reason, the two test electrode parts were changed to needle-like ones, and a special and very expensive test equipment that requires more accurate positioning of the two test electrode parts than before was separately developed. There is a need to. Further, since the accuracy of the alignment is required more than before, the time required for the inspection increases. This is also a bottleneck in cost reduction.

In the conventional method (A), wiring must be provided on the side surface of each element at the stage of the element state, which is not suitable for mass production.

In the conventional method (B), the insulating substrate and the high-resistance substrate include materials that cannot be easily etched, such as sapphire (Al ₂ O ₃ ) and silicon carbide (SiC). Even if it can be etched, in a normal semiconductor process, etching of at most a few microns is realistic from the processing time.
The substrate of the light emitting element is usually about 100 to 450 microns, which is too time-consuming and unsuitable for mass production.

In the conventional method (C), the thickness of the substrate is usually about 100 microns or more, but the semiconductor thin film layer laminated thereon is several microns. As in the above problem (B), it is difficult to perform etching or the like, and even if it is formed, a portion consisting only of a semiconductor thin film layer having a thickness of several microns is very fragile in the subsequent steps and hardly becomes a practical element. .

The main object of the present invention is to overcome the above-mentioned drawbacks and to provide a compound semiconductor thin film layer-containing substrate having a light emitting layer having a compound semiconductor thin film layer formed on an insulating substrate or a high-resistance substrate. When a groove is provided by the dicer, a plurality of light-emitting portions are formed at the boundary of the groove, and a plurality of light-emitting portions are separated along the groove by a predetermined separating means. It has high productivity and reproducibility, can reduce the device size without reducing the performance without compromising the performance, and has electrodes on the front and back of the device that can be easily handled in the device mounting process. An object of the present invention is to provide an element structure and a method for manufacturing the same.

[0019]

In order to solve the above problems, a compound semiconductor light emitting device according to the present invention comprises a lower compound semiconductor thin film layer and an upper compound semiconductor thin film layer on an upper surface of an insulating or high resistance substrate. An upper shallow groove extending from the upper side of the substrate with a compound semiconductor thin film layer to the lower compound semiconductor thin film layer is provided for the substrate with a compound semiconductor thin film layer formed with the light emitting layer having the semiconductor thin film layer. Thus, a plurality of light emitting portions are formed with the upper shallow groove as a boundary, and the compound semiconductor light emitting element is formed by separating the light emitting portion along the upper shallow groove using a predetermined cutting means such as a dicer. A first electrode formed on the upper surface side of the upper compound semiconductor thin film layer, a second electrode formed on the lower surface side of the substrate, and the compound semiconductor thin film layer along the upper shallow groove. Base An upper deep groove formed further deeper into the substrate from the upper side, and at least one groove formed on a lower side per one light emitting portion, wherein the groove is formed from a lower surface side of the substrate. A lower groove formed in the substrate at a predetermined angle other than zero with the upper deep groove, and having a depth larger than a thickness obtained by subtracting the depth of the upper deep groove from the thickness of the substrate with a compound semiconductor thin film layer; And a creepage surface of the upper deep groove portion, a creepage surface of a through-hole portion located at an intersection of the lower groove portion and the upper deep groove portion, and a creepage surface of the lower groove portion, and the lower compound semiconductor thin film layer And a thin film electrode wiring portion formed of a thin film electrode wiring extending from the first electrode to the second electrode.

By this means, electrodes are provided on the upper and lower surfaces of the compound semiconductor light emitting device, respectively, and the electrodes are connected to a predetermined compound semiconductor thin film layer. Further, since a dicer can be used, processing can be performed in a shorter time than in the case of etching. In addition, since the electrodes are provided on the lower surface side of the compound semiconductor light emitting device before the light emitting portion is formed and separated into the compound semiconductor light emitting device, the conventional light emission amount inspection method can be directly performed. . In this case, the meaning of the word of the compound semiconductor light emitting device includes a completed product mounted on a package or the like.

More preferably, the material of the thin film electrode wiring portion is any one of Au, Al, and Ti / Au.
These materials can be easily formed by a vapor deposition device or a sputtering device, and have excellent adhesion to a substrate.

Further, the material of the thin film electrode wiring portion is IT
It can be any of O, SnO ₂ , and ZnO.
By using this material, the thin-film electrode wiring portion provided on the side surface of the compound semiconductor light-emitting element is formed as a transparent conductive thin film, so that the translucency of the portion is improved. Luminous efficiency is improved.

Further, the first electrode formed on the upper surface side of the upper compound semiconductor thin film layer is provided with an ohmic metal once adhered to the upper surface of the upper compound semiconductor thin film layer and annealed. It is more preferred to have a transparent conductive thin film formed by removing all or part of only the ohmic metal and replacing it. By once attaching an ohmic metal to the upper surface of the upper compound semiconductor thin film layer and performing annealing treatment, a thin alloy layer of the compound semiconductor and the ohmic metal is formed on the uppermost surface of the upper compound semiconductor thin film layer. With this alloy layer, ohmic contact can be made between the metal and the compound semiconductor, so that current can flow smoothly. However, this ohmic metal
Since it does not transmit light, there is a problem in terms of luminous efficiency. If the ohmic metal is made into an ultrathin film of about 100 angstroms, light will be transmitted to some extent, but it will still be absorbed, leaving a problem in light emission efficiency. Controlling the ohmic metal to an ultrathin film of about 100 Å has a problem in reproducibility and is inferior in mass productivity. As an example of the solution, there is a method in which an ohmic metal is formed only on a part of the light emitting surface, and the current is diffused as much as possible in the upper compound semiconductor thin film layer. However, this can be usually used when the thickness of the upper compound semiconductor thin film layer can be increased or when the resistivity of the upper compound semiconductor thin film layer is small.
It is not suitable for blue LEDs such as gallium nitride. Another solution is the one described above, in which once the ohmic metal is deposited and annealed on the upper surface of the upper compound semiconductor thin film layer, only a part of the ohmic metal is removed, and the transparent conductive It forms a thin film. According to this, a thin alloy layer of the compound semiconductor and the ohmic metal is formed on the uppermost surface of the upper compound semiconductor thin film layer, and the thin alloy layer remains when the ohmic metal is removed. If a transparent conductive thin film is formed thereon, current can be diffused and flow through the entire compound semiconductor light emitting device, and there is no problem in terms of luminous efficiency.

In addition, as described above, the present invention is not limited to the case where the substrate is an insulating or high-resistance substrate, but is also effective when a normal semiconductor substrate is used, that is, when electrodes are taken from above and below by a conventional method. is there. That is, a compound semiconductor light emitting device having a lower compound semiconductor thin film layer, an upper compound semiconductor thin film layer, and an electrode formed on the upper surface side of the upper compound semiconductor thin film layer on the upper surface side of the semiconductor substrate In the above, after the ohmic metal is once adhered to the upper surface of the upper compound semiconductor thin film layer and annealed, the transparent conductive thin film is formed by removing all or a part of the ohmic metal alone and forming the same instead. It is preferable to have As a result, as described above, the upper compound semiconductor thin film layer is thin or has high resistivity, and current cannot be diffused to the entire light emitting layer only by providing an electrode on a part of the surface of the compound semiconductor light emitting device. It is generally accepted as a solution for the case. Especially in recent years MBE
(Molecular beam crystal growth method), compound semiconductor light emitting devices made by MOVPE (organic metal vapor phase epitaxy), as the film thickness increases, the productivity per unit time decreases and the material cost increases. In many cases, it is desired to produce a high-performance compound semiconductor light emitting device. Therefore, an InGaAlP-based high-brightness LED, InGa
It is particularly effective for AlN-based short wavelength LEDs and the like.

Further, a method of manufacturing a compound semiconductor light emitting device having an insulating or high resistance substrate can be realized as follows. For a substrate with a compound semiconductor thin film layer in which a light emitting layer having a lower compound semiconductor thin film layer and an upper compound semiconductor thin film layer is formed on the upper surface side of an insulating or high resistance substrate, from the light emitting layer side Forming a plurality of upper shallow grooves linearly at a depth reaching the lower compound semiconductor thin film layer, thereby forming a light emitting portion with a portion sandwiched between the upper shallow grooves as a light emitting portion; A first electrode forming step of forming a first electrode on the upper surface side of the layer;
An upper deep groove portion forming step of forming an upper deep groove portion formed of a groove having a predetermined depth smaller than the width of the upper shallow groove portion and reaching at least the substrate along a center line of the upper shallow groove portion using a dicer, Another groove formed by using a dicer from the lower side of the substrate at a predetermined angle other than zero degrees with respect to the upper deep groove portion, and at least one groove is provided for each light emitting portion, and A lower groove that forms a depth at least larger than a size obtained by subtracting the predetermined depth from the thickness of the substrate with a compound semiconductor thin film layer, a lower groove that forms a through hole at an intersection with the upper dicer groove, and A step of forming a through-hole portion, and utilizing the through-hole portion, a thin-film electrode formed of thin-film electrode wiring from the side of at least the lower compound semiconductor thin-film layer to the side of the substrate connected to the light-emitting portion. Forming a thin film electrode wiring portion forming step of forming a wiring portion; and forming a second electrode paired with the first electrode on the lower surface side of the substrate simultaneously with or before or after the thin film electrode wiring portion forming step. A second electrode forming step, and a separating step of separating each light emitting unit into compound semiconductor light emitting elements by using predetermined cutting means such as a dicer along the upper shallow groove formed in the upper deep groove forming step. And it has.

At the end of the above step, the lower compound semiconductor thin film layer and the second electrode (ie, positive electrode or negative electrode) provided on the lower surface side of the substrate are connected via the thin film electrode wiring. It is electrically connected. On the other hand, the first electrode is also electrically connected to the upper compound semiconductor thin film layer.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the compound semiconductor light emitting device according to the present invention will be described below with reference to FIGS. FIG. 1 is a perspective view showing a completed state of the compound semiconductor light emitting device according to the first embodiment of the present invention, and FIGS. 2A and 2B are first views of the compound semiconductor light emitting device according to the present invention. The first half of the manufacturing process (light emitting portion forming process, first electrode forming process,
3 (A), 3 (B), and 3 (B) showing a step of forming an electrode serving as a base point of a thin film wiring on an N-cladding layer.
FIG. 4 is a partial cross-sectional view showing the middle part of the subsequent manufacturing process (the upper deep groove forming step and the lower groove and through hole forming step). FIG. A part forming step, a second electrode forming step,
It is a fragmentary sectional view showing the stage of (separation step). FIG. 5 is a partial plan view showing the latter half of the manufacturing process (thin film electrode wiring part forming step, second electrode forming step, and separation step), and FIG. 6 is the latter half of the manufacturing process (thin film electrode). FIG. 9 is a partial perspective view showing a stage of a wiring part forming step, a second electrode forming step, and a separating step). FIG. 7 shows the latter half of the manufacturing process (a thin film electrode wiring portion forming process, a second electrode forming process,
FIG. 8A is a schematic perspective view showing the state of the formed groove from another angle at the stage of (separation step), and FIG. 8A is the latter half of the manufacturing step (the thin film electrode wiring section forming step and the second step). Schematic plan view showing stages of an electrode forming process and a separating process),
FIG. 8B is a schematic front view showing the latter half of the manufacturing process (the thin film electrode wiring portion forming process, the second electrode forming process, and the separating process), and FIG. 9A is the manufacturing process. FIG. 9B is a schematic right side view showing the second half (thin film electrode wiring section forming step, second electrode forming step, and separation step), and FIG. A schematic bottom view showing the steps of a process, a second electrode formation process, and a separation process).
FIG. 10 is a schematic perspective view from the bottom side showing the latter half of the manufacturing process (the thin film electrode wiring portion forming process, the second electrode forming process, and the separating process). 2B and FIGS. 3 and 4 show a positive electrode portion 15 which is a first electrode described later.
It is a longitudinal cross-sectional view passing through the center of 0.

The compound semiconductor light emitting device 15 according to the first embodiment of the present invention is as shown in FIG. That is,
In general, according to claim 1, the compound semiconductor light emitting element 15 is a positive electrode which is a first electrode formed on the upper surface side of the P-clad layer 103 and the contact layer 104 which are the upper compound semiconductor thin film layers. 150, a negative electrode 160 as a second electrode formed on the lower surface side of the sapphire substrate 100 as the substrate, and a substrate with a compound semiconductor thin film layer along the upper shallow groove (formed around the upper part of 107). (Corresponding to 100, 101, 102 and 103) Upper deep grooves formed deeper from the upper side until reaching the inside of the sapphire substrate 100 (parts 170 located on the left and right side surfaces of the compound semiconductor light emitting device 15 in FIG. 1 are removed). Part) and one light emitting part (101, 102 and 103)
At least one groove (two in this embodiment) is formed on the lower side of the sapphire substrate 100 from the lower surface side of the sapphire substrate 100 (see FIG. 1). Compound semiconductor light emitting device 15
And a predetermined angle other than zero degrees (90 ° in this embodiment) with the compound semiconductor thin film layer-attached substrate (100, 101, and 102). 103)
A lower groove 220 having a depth larger than the depth of the upper deep groove (a portion obtained by removing the portions 170 located on the left and right side surfaces of the compound semiconductor light emitting device 15 in FIG. 1) from the thickness of the lower groove 220; 220 and an upper deep groove portion (1 located on the left and right side surfaces of the compound semiconductor light emitting device 15 in FIG.
70), the lower groove 22
A through-hole located at the intersection of 0, 220 and an upper deep groove (a portion of the compound semiconductor light-emitting device 15 excluding portions 170 located on the left and right side surfaces of the compound semiconductor light-emitting device 15 [FIG. 17 located on the left and right sides
From the N-cladding layer 101, which is the lower compound semiconductor thin film layer, via the creepage of the portion where the zero portion has been removed and the intersection of the two 220] and the creepage of the lower grooves 220, 220. A thin-film electrode wiring portion 170 including a thin-film electrode wiring reaching the negative electrode 160 as the second electrode is provided on the periphery.

A manufacturing process for forming the above configuration will be described. First, a light emitting portion forming step which is the first half of the manufacturing process, a first electrode forming step, and an N-clad layer 1
Electrode to be the base point of thin film wiring to 01 (middle position electrode part)
The forming process will be described with reference to FIG.

The light emitting portion forming step is as follows (see FIG. 2A). Sapphire substrate 1 as an insulating substrate
And an N-cladding layer 101 as a compound semiconductor thin film layer below the upper surface of the sapphire substrate 100.
Grow. An active layer 102 is grown on the upper surface of the N-clad layer 101. On the upper surface of the active layer 102, a P-clad layer 103 and a contact layer 104 are grown as an upper compound semiconductor thin film layer. This step can be performed using a forming means such as a general vapor phase epitaxial method or a liquid phase epitaxial method. Here, the contact layer 104 refers to a highly doped layer, a layer having a relatively small band gap, or the like, which facilitates ohmic contact in a later step. Contact layer 104
Can be omitted.

Thereafter, an ohmic electrode portion 105 made of a thin translucent metal is formed on almost the entire upper surface of the contact layer 104 by means such as a vacuum evaporation method.
A bonding electrode portion 106 made of metal is formed in a substantially circular shape substantially at the center of the ohmic electrode portion 105 using a means such as a vacuum deposition method. The bonding electrode 106
Is an electrode to which one end of the wire is bonded at the time of wire bonding. Also, ohmic electrode part 1
The positive electrode part 150 as the first electrode is constituted by the bonding electrode part 05 and the bonding electrode part 106.

Thereafter, as a continuation of the light emitting section forming step, as shown in FIG. 2B, predetermined intervals (for example, about 200 μm) are vertically and horizontally parallel from the upper surface side of the substrate 10 with the compound semiconductor thin film layer. The upper shallow groove portion 200 is provided at intervals by using digging means such as etching. The depth reaches the N-cladding layer 101, is slightly below the upper surface of the N-cladding layer 101, and is N-cladding even if it is deep.
It is preferable to reach the lower surface of the cladding layer 101. At this stage, a plurality of light emitting portions 11 have been formed (end of the light emitting portion forming step).

Next, a step of forming an electrode (middle position electrode portion 107) serving as a base point of the thin film wiring on the N-clad layer 101 is performed. A middle position electrode portion 107 made of a thin film metal is formed on the entire bottom surface of the upper shallow groove portion 200 by means such as a vacuum evaporation method. The upper surface of the middle position electrode unit 107 is N-
The height is substantially the same as the upper surface of the cladding layer 101 and is not higher than that (at least the P-cladding layer 1).
03).

Next, a description will be given, with reference to FIG. 3, of an upper deep groove forming step and a lower groove and through hole forming step which are the middle part of the manufacturing process. The upper deep groove forming step is as follows. As shown in FIG. 3A, a groove is formed from the upper surface side of the substrate 10 with a compound semiconductor thin film layer using a dicer (not shown). A resist layer 220 is provided so as to cover the portion formed on the upper surface than 102 so as not to cover the portion. Thereafter, the upper shallow groove 2 is formed along the center line of the bottom surface of the upper shallow groove 200 using a dicer.
00 and a predetermined depth at least reaching the substrate 100 (for example, the substrate 1 with a compound semiconductor thin film layer).
(Preferably about 2/3 of the thickness of 0). The part where the groove is formed is shown in FIG. In FIG. 3A, 210
The position of “a” indicates the bottom of the dicer removing portion 210. FIG. 3 shows a state in which the dicer removed portion 210 is removed.
(B) shows the upper deep groove portion 211. The position of the bottom of the upper deep groove 211 is indicated as 211a.

Next, the steps of forming the lower groove and the through hole are as follows. From the lower surface side of the sapphire substrate 100,
A lower groove 220, which is another groove, is formed. The lower groove 220 is formed in a direction perpendicular to the upper deep groove 211.
Two light emitting units are provided for each light emitting unit 11 (see FIG. 6). The ceiling of the lower groove 220 is at the position 220a. The dimension from the ceiling 220a to the lower surface of the sapphire substrate 100, that is, the depth of the lower groove 220, is at least slightly larger than the dimension obtained by subtracting the predetermined depth from the thickness of the substrate 10 with a compound semiconductor thin film layer (compound). It is preferable that the thickness is slightly larger than 1/3 of the thickness of the substrate 10 with a semiconductor thin film layer).

When the lower groove 220 is formed, the lower groove 220 (for example, the substrate 10 with a compound semiconductor thin film layer) is formed.
At the intersection of the upper deep groove 211 (preferably about ／ of the thickness of the substrate 10 with a compound semiconductor thin film layer).
Since 0 and 211 overlap, the overlapping portion is formed as the through-hole 230 (see FIGS. 5, 7 to 10).

Next, a description will be given of a thin-film electrode wiring portion forming step, a second electrode forming step, and a separating step, which are the latter half of the manufacturing process, with reference to FIGS. The thin-film electrode wiring portion forming step and the second electrode forming step can be performed from the front side and the back side of the substrate 10 with the compound semiconductor thin film layer, respectively, by means such as a vacuum evaporation method. At this time, since there is the through hole 230, the middle position electrode 107,
Side surface of N-cladding layer 101 and sapphire substrate 10
0, the lower surface of the sapphire substrate 100, and the ceiling 220
a is electrically connected. As a thin-film electrode, in order to secure adhesion to the sapphire substrate 100,
As the material, any of Au, Al, and Ti / Au is preferable. Thereafter, the resist layer 220 is removed.

FIG. 4 shows the state after the formation. The electrode on the lower surface of the sapphire substrate 100 is the negative electrode part 160 as the second electrode, and the other part is the thin film electrode wiring part 170. .

Next, the separation step is performed as follows.
When each light emitting unit 11 is separated by the following separating means at the position of the broken line 300, a plurality of compound semiconductor light emitting elements 15 are formed. As a separating means at this time, a dicer may be used, or the lower surface side of the sapphire substrate 100 may be mounted on a stretchable and sticky sheet having an upper surface, expanded and divided at a position indicated by a broken line 300. There is.

The state after this separation step is the state shown in FIG. Therefore, at the end of this process,
In the compound semiconductor light emitting device 15, the P-clad layer 103 and the contact layer 104, which are the upper compound semiconductor thin film layers, are electrically connected to the positive electrode portion 150 formed on the upper surface side of the compound semiconductor light emitting device 15. I have. Further, the negative electrode portion 160 formed on the lower surface of the compound semiconductor light emitting element 15 is connected to the lower N- clad layer 101 which is a lower compound semiconductor thin film layer via the thin film electrode wiring portion 170 and the middle position electrode portion 107. It is electrically connected.

Accordingly, the conventional electrode installation configuration in which the positive electrode is provided on the upper surface of the compound semiconductor light emitting device 15 and the negative electrode is provided on the lower surface of the compound semiconductor light emitting device 15 is different from the compound semiconductor light emitting device having the insulating substrate. 15 as well.

Therefore, the compound semiconductor light emitting device 1
In order to inspect the light emission amount of No. 5, a conventional inspection apparatus can be used as it is, and it can be efficiently performed immediately before the separation step (that is, a state in which the plurality of light emitting units 11 are connected) as in the conventional case. .

In the above embodiment, the compound semiconductor light emitting device 15 having a square upper surface has been described as a representative example. However, it goes without saying that, for example, the upper surface may have a strip shape. In addition, the lower groove 220 is provided with one light emitting unit 11.
One contact may be used, or three or more contacts may be used. Also, the upper deep groove 211 and the lower groove 220 need not be orthogonal to each other. In addition, the positive electrode portion 150 can be formed at any stage after the initial stage of processing the substrate 10 with the compound semiconductor thin film layer. Further, the negative electrode section 160 may be formed separately instead of being formed at the same time as the thin-film electrode wiring section 170. Further, the thin film electrode wiring portion 170 may be formed instead of providing the middle position electrode portion 107. At this time, the negative electrode part 160 formed on the lower surface of the compound semiconductor light emitting element 15
Is electrically connected to the N-clad layer 101 as the lower compound semiconductor thin film layer via the thin film electrode wiring portion 170. Also, the case of a substrate having an insulating property such as the sapphire substrate 100 has been described, but the same applies to a case of a high resistance, and a description thereof will be omitted.

Next, as a second embodiment according to the present invention, means for improving the amount of light transmission of the positive electrode portion 150 of the above-described embodiment and transmission of light from the side surface of the compound semiconductor light emitting element 15 will be described. This will be described with reference to FIG. 11 together with the means for improving the amount. FIG. 11 is a sectional view showing a state before the separation step according to the second embodiment of the present invention.

First, as means for improving the light transmission amount of the positive electrode unit 150, the positive electrode unit 150 of the first embodiment is used.
Is changed, that is, the step of forming the ohmic electrode portion 105 and the bonding electrode portion 106 is changed as follows.

First, at the stage when the ohmic electrode portion 105 is formed, an annealing process is performed. After that, only the ohmic metal is removed except for the portion where the bonding electrode portion 106 is to be formed. Instead, a transparent conductive thin film (ITO)
Is formed. After that, the bonding electrode portion 106 is formed on the ohmic electrode portion 105. At this time, the bonding electrode part 106, the ohmic electrode part 105, and the transparent film part 108 partially overlap or come into contact with each other.

Therefore, a thin alloy layer of a compound semiconductor and an ohmic metal is formed on the uppermost surfaces of the P-clad layer 103 and the contact layer 104, which are the upper compound semiconductor thin film layers. When the ohmic metal is removed, the thin alloy layer is left, so that the current can be smoothly diffused and flow through the entire compound semiconductor light emitting device 15. In addition, there is no problem in terms of luminous efficiency.

On the other hand, the thin film electrode wiring section 170 provided on the side surface of the compound semiconductor light emitting element 15 is also made of a transparent conductive film (ITO, SnO ₂ , ZnO, etc.), so that the compound semiconductor light emitting element The amount of light transmitted from the 15 side surfaces is improved. In this case, the negative electrode 160, which is an electrode on the lower surface of the compound semiconductor light emitting element 15, may be an electrode made of metal.

Next, a third embodiment according to the present invention will be described with reference to FIGS. 12 and 13, which is a means for making the upper surface of the compound semiconductor light emitting device 15 die-bondable. FIG. 12A is a cross-sectional view showing a third embodiment of the present invention, FIG. 12B is a bottom view of a half of FIG. 12A, FIG. 12C is a left-side cross-sectional view of FIG. FIG.
FIG. 9 is a perspective view showing a third embodiment according to the present invention.

The difference from the first embodiment is as follows.
Is a point. The positive electrode section 150 is not provided with the bonding electrode section 106. That is, the positive electrode unit 150 includes the ohmic electrode unit 105. The negative electrode section 160 is made of a transparent conductive film (ITO, SnO ₂ ,
ZnO). The bonding electrode unit 106 is provided on the lower surface of the negative electrode unit 160 when the negative electrode unit 160 is formed. A protective film section 190 made of an insulating protective film (made of SiO ₂ or the like) is provided after the formation of the thin-film electrode wiring section 170. The formation is made at a position that covers at least from the contact layer 104 to the upper part of the thin film electrode wiring portion 170.

By forming as described above, the upper surface side of the compound semiconductor light emitting element 15 can be die-bonded. Further, the compound semiconductor light emitting element 15 serving as a light emission observation surface
Since the negative electrode portion 160 on the lower surface side of the substrate is made of a transparent conductive film, the translucency of the portion is improved and the luminous efficiency is improved.
Further, a so-called PN junction (P-cladding layer 103, active layer 1) near the upper surface side of compound semiconductor light emitting element 15 is formed.
02, the junction portion of the N-cladding layer 101) is on the die bond side, so that the heat radiation characteristics can be remarkably improved. Therefore, in the compound semiconductor light emitting device 15, a current can flow more than before, and the luminance of the compound semiconductor light emitting device 15 can be improved.

Next, a fourth embodiment according to the present invention, in which a compound semiconductor light emitting device is a blue semiconductor laser, will be described with reference to FIG. FIG. 14 is a perspective view showing a fourth embodiment according to the present invention.

The fourth embodiment is almost the same as the third embodiment. The major differences are the following two points. The thin film layer of the compound semiconductor is a semiconductor laser. Negative electrode part 1 on the lower surface side of compound semiconductor light emitting element 15
60 is a metal electrode. The material of the negative electrode part 160 is Ti / Au, and the material of the positive electrode part 150 is Ni / Au.
Ti / Au. Reference numeral 109 denotes a current element layer (for example, n-GaN).

Therefore, the PN junction of the compound semiconductor light emitting element 15 can be fixed to the heat sink side.
The heat radiation characteristics can be remarkably improved. Therefore, in the compound semiconductor light emitting device 15, a current can flow more than before, and the luminance of the compound semiconductor light emitting device 15 can be improved.

[0055]

As described above, in the compound semiconductor light emitting device according to the present invention, the lower compound semiconductor thin film layer and the upper compound semiconductor thin film layer are formed on the upper surface side of the insulating or high resistance substrate. By providing an upper shallow groove extending from the upper side of the substrate with a compound semiconductor thin film layer to the lower compound semiconductor thin film layer with respect to the substrate with the compound semiconductor thin film layer of the compound semiconductor in which the light emitting layer is formed. A compound semiconductor light emitting device formed by forming a plurality of light emitting portions bordering on the upper shallow groove portion and separating the light emitting portion along the upper shallow groove portion using a predetermined cutting means such as a dicer, A first electrode formed on the upper surface side of the upper compound semiconductor thin film layer, a second electrode formed on the lower surface side of the substrate, and the substrate with the compound semiconductor thin film layer along the upper shallow groove portion An upper deep groove portion formed so as to reach the inside of the substrate further deeper from the upper side, and at least one groove formed on a lower side per one light emitting portion, wherein the substrate is formed from a lower surface side of the substrate. A lower groove formed at a predetermined angle other than zero degrees with the upper deep groove, and having a depth larger than a dimension obtained by subtracting the depth of the upper deep groove from the thickness of the substrate with a compound semiconductor thin film layer; From the lower compound semiconductor thin film layer via the creepage of the upper deep groove, the creepage of the through-hole located at the intersection of the lower groove and the upper deep groove, and the creepage of the lower groove. And a thin film electrode wiring portion formed of a thin film electrode wiring reaching the second electrode.

By this means, electrodes are provided on the upper and lower surfaces of the compound semiconductor light emitting device, respectively, and the electrodes are connected to a predetermined compound semiconductor thin film layer. Therefore, the step of mounting the compound semiconductor light emitting device on a package or the like becomes easy. Further, the size of the compound semiconductor light emitting device can be reduced without impairing the performance. Further, since a dicer is used, processing can be performed in a shorter time than in the case of etching. Further, before the light emitting portion is formed and separated into a compound semiconductor light emitting device, an electrode is provided on the lower surface side of the compound semiconductor light emitting device as in the related art,
The conventional light emission amount inspection method can be performed as it is. Accordingly, mass productivity is high and manufacturing cost can be reduced.

Further, in the compound semiconductor light emitting device according to the present invention, more preferably, the material of the thin film electrode wiring portion is A
u, Al, or Ti / Au. This material has good adhesion to the substrate, and is preferable from the viewpoint of improving the reliability of the compound semiconductor light emitting device.

Further, in the compound semiconductor light emitting device according to the present invention, the material of the thin film electrode wiring portion is made of ITO, SnO ₂ , Z
It was stated that any of nO could be used. By using this material, the thin-film electrode wiring portion provided on the side surface of the compound semiconductor light-emitting element is formed as a transparent conductive thin film, so that the translucency of the portion is improved. Luminous efficiency is improved. Therefore, the size of the compound semiconductor light emitting device required for commercialization with the same luminous efficiency can be reduced, so that the manufacturing cost can be further reduced.

Further, in the compound semiconductor light emitting device according to the present invention, the first electrode formed on the upper surface side of the upper compound semiconductor thin film layer is once in ohmic contact with the upper surface of the upper compound semiconductor thin film layer. After the metal was deposited and annealed, it was more preferable to remove all or part of the ohmic metal only and to form a transparent conductive thin film instead.

By using this means, in a compound semiconductor light emitting device (a normal light emitting diode or the like) of a type in which the upper surface side of the upper compound semiconductor thin film layer is used as a light emission observation surface, an ohmic electrode positioned on the light emission observation surface side Since the portion is replaced with a transparent conductive film, the light transmittance is improved, and the luminous efficiency of the compound semiconductor light emitting device on the luminescence observation surface side is improved.
Therefore, the size of the compound semiconductor light emitting device required for commercialization with the same luminous efficiency can be reduced, so that the manufacturing cost can be further reduced.

Further, the method for manufacturing a compound semiconductor light emitting device according to the present invention is characterized in that a light emitting layer having a lower compound semiconductor thin film layer and an upper compound semiconductor thin film layer on an upper surface side of an insulating or high resistance substrate is provided. The upper shallow groove portion is formed by linearly forming a plurality of upper shallow grooves having a depth from the light emitting layer side to the lower compound semiconductor thin film layer on the substrate with the compound semiconductor thin film layer of the formed compound semiconductor. Forming a first electrode on the upper surface side of the upper compound semiconductor thin film layer; and forming a first electrode on the upper surface side of the upper compound semiconductor thin film layer by using a dicer. An upper deep groove forming step of forming an upper deep groove formed of a groove having a predetermined depth which is smaller than the width of the upper shallow groove along the center line and at least reaches the substrate; Predetermined corner of Another groove formed by using a dicer from the lower side of the substrate, wherein at least one groove is provided for each of the light emitting portions, and the depth of the groove is determined from the thickness of the substrate with a compound semiconductor thin film layer. By the lower groove portion formed at least larger than the dimension obtained by reducing the predetermined depth,
A lower groove and a hole forming step of forming a hole at an intersection with the upper dicer groove, and a side surface of at least the lower compound semiconductor thin film layer which is the light emitting portion using the hole. A thin-film electrode wiring portion forming step of forming a thin-film electrode wiring portion composed of a thin-film electrode wiring from the side surface of the substrate connected thereto, and simultaneously with or before or after the thin-film electrode wiring portion forming step, on the lower surface side of the substrate; A second electrode forming step of forming a second electrode paired with the first electrode, and using a predetermined cutting means such as a dicer along the upper shallow groove formed in the upper deep groove forming step. A separating step of separating the light emitting units into compound semiconductor light emitting elements.

At the end of the above step, the lower compound semiconductor thin film layer and the second electrode (ie, positive electrode or negative electrode) provided on the lower surface of the substrate are connected via the thin film electrode wiring. It is electrically connected. On the other hand, the first electrode is also electrically connected to the upper compound semiconductor thin film layer. Therefore, as described above, the manufacturing cost can be reduced. In addition, since this manufacturing method does not include a step having low reproducibility in production, reproducibility is high.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a completed state of a compound semiconductor light emitting device according to a first embodiment of the present invention.

FIGS. 2A and 2B are diagrams illustrating a first half of a manufacturing process (a light emitting portion forming process, a first electrode forming process, and a first forming process) in the compound semiconductor light emitting device according to the first embodiment of the present invention; N-
An electrode forming step that is the starting point of thin film wiring on the cladding layer)
FIG. 4 is a partial cross-sectional view showing a stage.

FIGS. 3A and 3B are partial cross-sectional views showing the stages of the middle part of the manufacturing process subsequent to FIG. 2 (the upper deep groove forming step and the lower groove and through hole forming step). .

FIG. 4 is a partial cross-sectional view showing a latter half of a manufacturing process (a thin film electrode wiring portion forming process, a second electrode forming process, and a separating process) subsequent to FIG. 3;

FIG. 5 shows the latter half of the manufacturing process (the thin film electrode wiring portion forming process,
FIG. 9 is a partial plan view showing a stage of a second electrode forming step and a separating step).

FIG. 6 shows the latter half of the manufacturing process (the thin film electrode wiring portion forming process,
FIG. 4 is a partial perspective view showing a stage of a second electrode forming step and a separating step).

FIG. 7 shows the latter half of the manufacturing process (the thin film electrode wiring portion forming process,
In the second electrode forming step and the separating step),
It is the schematic perspective view which showed the situation of the formed groove from another angle.

8A is a schematic plan view showing a stage of a latter half of a manufacturing process (a thin film electrode wiring portion forming process, a second electrode forming process, and a separating process), and FIG. 8B is a schematic front view thereof. FIG.

9A is a schematic right side view showing the latter half of the manufacturing process (a thin film electrode wiring portion forming step, a second electrode forming step, and a separating step), and FIG. 9B is a schematic right side view thereof. It is a bottom view.

FIG. 10 is a schematic perspective view from the bottom side showing a stage of a latter half of a manufacturing process (a thin film electrode wiring portion forming process, a second electrode forming process, and a separating process).

FIG. 11 is a cross-sectional view showing a state before a separation step according to the second embodiment of the present invention.

12A is a sectional view showing a third embodiment according to the present invention, FIG. 12B is a bottom view of half of FIG. 12A, and FIG. 12C is a left sectional view of FIG.

FIG. 13 is a perspective view showing a third embodiment according to the present invention.

FIG. 14 is a perspective view showing a fourth embodiment according to the present invention.

[Explanation of symbols]

 Reference Signs List 15 compound semiconductor light emitting device 100 sapphire substrate (substrate) 101 N-cladding layer (lower compound semiconductor thin film layer) 150 positive electrode (first electrode) 160 negative electrode (second electrode) 170 thin film electrode wiring section 220 under Gutter

Claims (6)

[Claims] 1. A substrate having a compound semiconductor thin-film layer comprising a light-emitting layer having a lower compound semiconductor thin-film layer and an upper compound semiconductor thin-film layer formed on an upper surface of an insulating or high-resistance substrate. By providing an upper shallow groove from the upper side of the substrate with a compound semiconductor thin film layer to the lower compound semiconductor thin film layer, a plurality of light emitting portions are formed bordering on the upper shallow groove portion. In a compound semiconductor light emitting device formed by separating using a predetermined cutting means such as a dicer along the upper shallow groove portion, a first electrode formed on an upper surface side of the upper compound semiconductor thin film layer; A second electrode formed on the lower surface side of the substrate, an upper deep groove portion formed along the upper shallow groove portion from the upper side of the substrate with a compound semiconductor thin film layer further deeply into the substrate, At least one groove formed on the lower side of each of the light emitting portions, formed at a predetermined angle other than zero degree with the upper deep groove portion in the substrate from the lower surface side of the substrate, and a compound semiconductor thin film A lower groove portion having a depth larger than a size obtained by subtracting the depth of the upper deep groove portion from the thickness of the layered substrate, a creepage surface of the upper deep groove portion, at an intersection of the lower groove portion and the upper deep groove portion. Via the creepage of the located through-hole, and the creepage of the lower groove,
A compound semiconductor light emitting device comprising: a thin film electrode wiring portion including a thin film electrode wiring from the lower compound semiconductor thin film layer to the second electrode. 2. The material of the thin film electrode wiring portion is Au, A
2. The compound semiconductor light emitting device according to claim 1, wherein said compound semiconductor light emitting device is any one of l and Ti / Au. 3. The thin film electrode wiring portion is made of ITO, S
_2. The compound semiconductor light-emitting device according to claim 1, wherein the compound semiconductor light-emitting device is any one of nO ₂ and ZnO. 4. The compound semiconductor light emitting device according to claim 1, wherein the first electrode formed on the upper surface side of the upper compound semiconductor thin film layer is disposed once with respect to the upper surface of the upper compound semiconductor thin film layer. A compound semiconductor light-emitting device comprising a transparent conductive thin film formed by attaching or removing an ohmic metal and then removing all or a part of the ohmic metal, instead of the ohmic metal. 5. A compound having a lower compound semiconductor thin film layer, an upper compound semiconductor thin film layer, and an electrode formed on a further upper surface side of the upper compound semiconductor thin film layer on the upper surface side of the semiconductor substrate. In the semiconductor light emitting device, the electrode is formed by attaching an ohmic metal once to the upper surface of the upper compound semiconductor thin film layer and annealing the same, then removing all or a part of the ohmic metal alone, and forming a transparent electrode instead. A compound semiconductor light emitting device comprising a conductive thin film. 6. A compound semiconductor thin film layer-equipped substrate in which a light emitting layer having a lower compound semiconductor thin film layer and an upper compound semiconductor thin film layer is formed on the upper surface side of an insulating or high-resistance substrate. Forming a plurality of upper shallow grooves linearly from the light emitting layer side to the lower compound semiconductor thin film layer by a plurality of upper shallow grooves, thereby forming a portion sandwiched by the upper shallow grooves as a light emitting section; A first electrode forming step of forming a first electrode on the upper surface side of the upper compound semiconductor thin film layer, and using a dicer, along a center line of the upper shallow groove, narrower than the width of the upper shallow groove and An upper deep groove forming step of forming an upper deep groove formed of a groove having a predetermined depth reaching at least the substrate, and using a dicer from the lower side of the substrate at a predetermined angle other than zero degree with respect to the upper deep groove. Another groove to be formed A lower groove portion provided at least one or more per one light emitting portion and having a depth at least larger than a thickness obtained by subtracting the predetermined depth from the thickness of the substrate with a compound semiconductor thin film layer; Forming a through-hole at the intersection with the dicer groove and forming a through-hole, and using the through-hole to form the light-emitting portion, at least from the side of the lower compound semiconductor thin film layer. A thin-film electrode wiring portion forming step of forming a thin-film electrode wiring portion composed of a thin-film electrode wiring over the side surface of the substrate, and simultaneously with or before or after the thin-film electrode wiring portion forming step, on the lower surface side of the substrate, A second electrode forming step of forming a second electrode paired with the first electrode, and a predetermined cutting means such as a dicer are used along the upper shallow groove formed in the upper deep groove forming step. Method of manufacturing a compound semiconductor light emitting device characterized by separating each emission portion and a compound semiconductor light-emitting device and forming isolation step.