JPH09275225A - Light emitting and receiving device and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent short-circuiting between the edge of a diffusion mask and an electrode of second conductivity type even in an impurity diffusion region with a small diffusion depth, by extending part of a layer insulating film from a first insulating film to an opening side wall to part of the impurity diffusion region. SOLUTION: An impurity diffusion region 13 of first conductivity type, for example, p-type, is formed on a base 11 made of a n-type semiconductor. In addition, a first insulating film 15 and a layer insulating film 17 are formed on the base 11 in this order. A p-type electrode 19 that is electrically connected with the impurity diffusion layer 13 and extends to the layer insulating film 17, is formed. However, part of the first insulating film 15 is gibbously expanded in an opening in the direction of lead-out of the electrode 19 of the first conductive type. Part of the layer insulating film 17 extends from the first insulating film 15 to at least part of the expanded portion 13 in the impurity diffusion layer. Thus the portion P of the first insulating film 15 in proximity to the opening 17a is covered with the portion 17x of the layer insulating film on the impurity diffusion layer without fail.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting / receiving element and a method for manufacturing the same. Here, the light emitting / receiving element is meant to include a light emitting diode, a photodiode, a light emitting diode array, and a photodiode array.

[0002]

2. Description of the Related Art A light emitting diode array is used as a light source of, for example, an electrophotographic optical printer. In the case of manufacturing such a light emitting diode array, second-conductivity-type impurity diffusion regions are formed at a predetermined pitch on a base made of a first-conductivity-type compound semiconductor. P that constitutes each light emitting unit
This is because each n-junction is formed. Each impurity diffusion region is generally formed by forming a diffusion mask having a plurality of openings on the lower surface of the first conductivity type and selectively thermally diffusing impurities of the second conductivity type into the underlying layer. To be done. As a suitable thermal diffusion method that can be used at that time, a vapor phase diffusion method or a solid phase diffusion method (for example, Japanese Patent Application No. 6-11572 of the present applicant).
A method according to JP-A No. 7 (Japanese Patent Laid-Open No. 7-321371). Details will be described later). In any of the diffusion methods, the impurities diffuse in a direction perpendicular to the ground plane of the base (hereinafter, also referred to as vertical diffusion) and also in a direction parallel to the ground plane (hereinafter, also referred to as lateral diffusion). Say.). Further, in any of the diffusion methods, the deeper the vertical diffusion depth, the larger the lateral diffusion amount. When the vertical diffusion depth is Xj and the lateral diffusion amount is ds, and if abnormal lateral diffusion does not occur, in the vapor phase diffusion method, for example, ds / Xj =
It is known that there is a relationship of 1.3 (for example, Document I: Trikeps WS64, page 20).

[0003]

By the way, when the light emitting diode array is constructed, the higher the resolution is, the narrower the pitch of the light emitting portions in the light emitting diode array becomes. Then, in order to narrow the pitch of each light emitting portion, it is necessary to reduce the lateral diffusion amount in each impurity diffusion region forming each light emitting portion.
Otherwise, the lateral diffusion portions will contact each other between the adjacent impurity diffusion regions, so that the respective light emitting portions cannot be separated. Further, when the impurity diffusion is performed by the vapor phase diffusion method, the emission intensity increases up to a certain depth Xjmax between the diffusion depth and the emission intensity in the impurity diffusion region and reaches a certain depth Xjmax. Shows a peak at which the emission intensity decreases. It is known that this Xjmax in the case of the vapor phase diffusion method is about 3 to 8 μm (for example, page 20 of Document I). Therefore, when the impurity diffusion region is formed by the vapor phase diffusion method while considering the emission intensity, at least 3.9 to 1 is formed in the impurity diffusion region.
A lateral diffusion of 0.4 μm (calculated on the basis of ds / Xj = 1.3) occurs. On the other hand, the applicant of the present application is, for example, Japanese Patent Application No. 6-115727 (JP-A-7-32137).
No. 1) claims a method of forming the impurity diffusion region of the light emitting and receiving element by a solid phase diffusion method. Specifically, there is a method in which a diffusion source thin film is formed on a predetermined portion of the base, the diffusion source thin film is covered with an annealing cap film, and the sample is heat-treated. According to this solid phase diffusion method, a desired emission intensity can be obtained even in an impurity diffusion region having an extremely shallow diffusion depth (for example, even if the diffusion depth is about 1 μm) as compared with the vapor phase diffusion method. ing. Therefore, according to this solid phase diffusion method, a light emitting diode having an impurity diffusion region with a small amount of lateral diffusion can be obtained. Therefore, this method was a preferable method when manufacturing a high resolution light emitting diode array.

However, the problem is not limited to the solid phase diffusion method, but the following problems may occur when the light emitting / receiving array is simply configured using the impurity diffusion region having a shallow diffusion depth. is there. This will be described with reference to FIG.

9A and 9B are a plan view and a sectional view taken along line I-I of a conventional typical light emitting diode having an impurity diffusion region having a deep diffusion depth. Further, FIG. 9C shows a light emitting diode having an impurity diffusion region having a shallow diffusion depth and having a conventional structure.
(B) It is sectional drawing by the same notation method. Further, in FIG. 9, 11 is a base made of a compound semiconductor of the first conductivity type, 13 is an impurity diffusion region of the second conductivity type, and 15 has an opening 15a, which is used as a diffusion mask when the impurity diffusion region is formed. A first insulating film, 17 is an interlayer insulating film provided on the first insulating film 15, 17a is an opening in the interlayer insulating film, and 19 is a second conductive side electrode.
Here, the first insulating film 15 functions as an element isolation film between each light emitting portion after the product is completed. In addition, the interlayer insulating film 1
Reference numeral 7 is mainly provided to prevent the first insulating film from having a pinhole or the like, which causes the base 11 and the second conductive side electrode 19 to be short-circuited. .

When the lateral diffusion amount is small because the diffusion depth of the impurity diffusion region 13 is shallow (see FIG. 9C), the impurity diffusion region 13 does not reach below the first insulating film 15. In some cases, the base 11 remains as it is in the vicinity P (see FIG. 9C) of the edge of the opening 15a of the first insulating film 15.
Therefore, the second conductive side electrode 19 and the base 11 are short-circuited in the vicinity P of the edge of the opening 15a of the first insulating film 15 (the pn junction formed by the base 11 and the impurity diffusion region 13 is formed). There is a risk of a short circuit occurring due to the second conductive side electrode 19).

Even when an impurity diffusion region having a shallow diffusion depth is used, a short circuit between the base and the second conductive side electrode at the edge of the diffusion mask (near the edge of the opening in the first insulating film) is caused. It is desired to realize a light emitting / receiving element having a preventable structure and a method suitable for manufacturing the same.

[0008]

Therefore, according to the first invention of this application, an underlayer made of a compound semiconductor of the first conductivity type is provided with an impurity diffusion region of the second conductivity type, and further, on the underlayer, A first insulating film having an opening and used as a diffusion mask at the time of forming the impurity diffusion region, an interlayer insulating film provided on the first insulating film, and an electrical connection to the impurity diffusion region. In a light receiving and emitting element comprising a second conductive side electrode formed to extend over the interlayer insulating film, the at least a part of the interlayer insulating film is formed on the first insulating film from the first insulating film. The second conductive-side electrode is provided so as to reach a part of the impurity diffusion region through the side wall of the opening of the first insulating film, and the second conductive-side electrode is provided via the interlayer insulating film portion reaching the impurity diffusion region. It is characterized by being.

In the first invention, considering the example of FIG. 9C, the vicinity P of the edge portion of the opening 15a of the first insulating film (see FIG.
(See (C)) is covered with a part of the interlayer insulating film, and the second conductive side electrode is provided via a part of the interlayer insulating film. Therefore, FIG. 9 (C)
A short circuit between the second conductive side electrode and the base at the P portion of is prevented.

Further, according to the manufacturing method according to the second invention of this application as a suitable method for manufacturing the light emitting and receiving element of the above first invention, the first insulating film is formed on the underlayer, and Compared with the opening (which has an effective area in the sense of forming a desired light-emitting portion; the same in the following fourth invention), and the second conductive-side electrode in the opening. Forming a first insulating film having a portion whose projection direction is partially convex or wholly extended along the extraction direction; and using the first insulation film as a mask Diffusing a second conductivity type impurity into the base by a solid phase diffusion method, and forming an impurity diffusion region in which the region is expanded by the expanded opening as compared to the desired impurity diffusion region, The first insulating film is formed on the first insulating film. A step of forming the interlayer insulating film so that a region reaching at least a part of the extended portion in the pure substance diffusion region is covered with a part of the interlayer insulating film; and an interlayer insulating film portion reaching the impurity diffusion region. And a step of forming a second conductive side electrode via the above.

According to the manufacturing method of the second aspect of the present invention, the impurity diffusion region is expanded in the extraction direction of the second conductive side electrode, and the interlayer insulation for preventing the short circuit between the second conductive side electrode and the base. The membrane portion is provided by utilizing this expanded portion. Therefore, the light emitting / receiving element according to the first aspect of the invention can be manufactured while securing the same area of the light receiving / emitting portion as the conventional one.

Further, when the first insulating film itself has excellent film quality and it is not necessary to provide an interlayer insulating film in particular, the following structure can be adopted. That is, according to the third invention of this application, an underlayer made of a compound semiconductor of the first conductivity type is provided with an impurity diffusion region of the second conductivity type, and further, an opening is formed on the underlayer, and A first insulating film used as a diffusion mask when forming the impurity diffusion region, and a second conductive side electrode electrically connected to the impurity diffusion region and formed to extend onto the first insulating film. In the light emitting and receiving element, a second insulating film is provided so as to extend from a part of the impurity diffusion region to at least a part of a side wall of the opening, and the second conductive side electrode is provided with the second insulating film. It is characterized in that it is provided via the above insulating film.

In the third invention, considering the example of FIG. 9C, the vicinity P of the edge of the opening 15a of the first insulating film (see FIG.
(See (C)) is covered with the second insulating film, and the second conductive side electrode is provided via the second insulating film. Therefore, P in FIG.
A short circuit between the second conductive side electrode and the base at a portion is prevented.
Further, according to the manufacturing method of the fourth invention of this application as a suitable method for manufacturing the light emitting and receiving element of the third invention, the desired opening of the first insulating film is formed on the base. A first insulating film in which a portion of the opening corresponding to the extraction direction of the second conductive side electrode is partially convex or wholly expanded along the extraction direction as compared with the A step of forming the second conductive type impurity in the base by a solid phase diffusion method using the first insulating film as a mask, and a region corresponding to the expanded opening is formed as compared with a desired impurity diffusion region. A step of forming an impurity diffusion region in which the second insulating film is extended, and a step of forming a second insulating film over at least a part of the extended portion in the formed impurity diffusion region on the first insulating film. The second conductive film is passed through the second insulating film. Characterized in that it comprises a step of forming a side electrode.

According to the manufacturing method of the fourth aspect of the present invention, the impurity diffusion region is expanded in the extraction direction of the second conductive side electrode, and the second conductive side electrode is prevented from being short-circuited with the base. The insulating film is provided by utilizing this expanded portion. Therefore, the light emitting / receiving element according to the third aspect of the invention can be manufactured while securing the same area of the light emitting / receiving portion as the conventional one.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the light emitting / receiving element and the method for manufacturing the same according to the present invention will be described below with reference to the drawings. However, the drawings used in the description are merely schematic views so that the present invention can be understood. Further, in each of the drawings, the same components are denoted by the same reference numerals, and the duplicate description thereof may be omitted. In the following description, an example in which each invention of the present application is applied to a light emitting diode (including a light emitting diode array) which is one type of light receiving and emitting element will be described.

1. First Embodiment FIGS. 1A and 1B are a plan view and a cross-sectional view taken along the line I-I for explaining the configuration of the light emitting diode according to the first embodiment. However, the cross-sectional views are shown only for the cut edges (the same applies to the following cross-sectional views).

This light emitting diode includes a base 11 made of a compound semiconductor of the first conductivity type, for example, N type, and the base 11.
And a P-type impurity diffusion region 13 formed in. Further, a first insulating film 15 having an opening 15a on the base 11 and used as a diffusion mask when the impurity diffusion region 13 is formed, and an interlayer insulating film provided on the first insulating film 15. A film 17 and a P-side electrode 19 which is electrically connected to the impurity diffusion region 13 and extends up to the interlayer insulating film 17 are provided. However, the first insulating film 15
When viewed in a plan view, a portion of the opening corresponding to the lead-out direction (rightward in FIG. 1) of the second conductive side electrode 19 is partially convex as compared with the desired opening along the lead-out direction. It has an expanded shape. For convenience of explanation, this expanded opening portion is referred to as a “convex expanded opening portion 15x”. In addition, the impurity diffusion region 1
7, the region is expanded by the amount of the opening portion 15x expanded in the convex shape as compared with the desired impurity diffusion region. For convenience of explanation, this expanded impurity diffusion region will be referred to as
It is referred to as an "extended portion 13a in the impurity diffusion region".
Note that in order to clarify the extended portion 13a in the impurity diffusion region, the corresponding portion is shown by hatching in the plan view of FIG. 1A (same in FIG. 3C). In addition, a part of the interlayer insulating film 17 partially extends from above the first insulating film 15 in the extended portion 13 in the impurity diffusion region.
It is provided so as to reach at least a part of a. For convenience of description, a portion of the interlayer insulating film 17 which reaches the impurity diffusion region 13 is referred to as an “interlayer insulating film portion 17x which reaches the impurity diffusion region”. Further, the P-side electrode 19 is provided via the interlayer insulating film portion 17x reaching the impurity diffusion region.

In the structure of the first embodiment, the vicinity P of the edge of the opening 17a in the first insulating film P (see FIG. 1B).
The reference) is surely covered by the interlayer insulating film portion 17x reaching the impurity diffusion region. Therefore, even when the amount of lateral diffusion during the formation of the impurity diffusion region 13 is small and the edge portion P remains as the base (that is, the first conductivity type), the second conductive side electrode 19 and the base are not formed. It is possible to prevent a short circuit between 11 and. Further, in the first embodiment, the impurity diffusion region is expanded in the extraction direction of the P-side electrode 19 and a part of the interlayer insulating film is provided on the part, so that part of the interlayer insulating film is expanded. Even if it is provided, it is possible to prevent the plane area of the light emitting portion from being reduced.

Next, an embodiment of the method of manufacturing the light emitting diode of the first embodiment will be described. 2 and 3 are process diagrams used for the description. Both figures are mainly shown by a sectional view corresponding to FIG.

As the base 11, for example, a GaAs substrate on which a GaAsP layer is epitaxially grown is used. However, in FIGS. 2 and 3, the GaAs substrate and the GaAsP layer are not distinguished and are shown as one body.
An AlN (aluminum nitride) film, for example, is formed as the first insulating film forming thin film 15y on the base 11 (FIG. 2).
(A)).

Next, in the first insulating film forming thin film 15y,
A portion of the opening 15a for forming the impurity diffusion region, the portion corresponding to the opening direction of the P-side electrode 19 (rightward in FIG. 2B) in the opening is larger than the desired opening. An opening 15a having an opening 15x that is convexly expanded along the direction is formed by a known lithography technique and etching technique. As a result, the first insulating film 15 is obtained (FIG. 2B).

Next, an impurity diffusion region is formed in this sample by the solid phase diffusion method. Therefore, in this embodiment,
First, the diffusion source thin film 21 and the annealing cap film 23 are formed in this order on this sample (FIG. 2C). Here, a SiO ₂ film containing ZnO is used as the diffusion source thin film 21, and an AlN film is used as the annealing cap film 23 here.

Next, the sample is heat-treated. For example, by heat treatment at a temperature of 700 ° C. for 0.5 hour, an impurity diffusion region 13 having a diffusion depth of 1 μm and an extension portion 13a can be formed in the underlayer 11 (FIG. 3A. )).

Next, the anneal cap film 23 and the diffusion source thin film 21 are removed. The annealing cap film 23 can be removed by, for example, hot phosphoric acid, and the diffusion source thin film 21 can be removed by, for example, buffered HF (hydrogen fluoride).

Next, a SiN film, for example, is formed as a thin film 17y for forming an interlayer insulating film on this sample (FIG. 3).
(B)).

Next, an opening 17a for exposing the impurity diffusion region 13 is formed in the thin film 17y for forming an interlayer insulating film by a known lithography technique and etching technique. However, at this time, the thin film 17y is patterned so that a part of the interlayer insulating film forming thin film 17y covers at least a part of the extended portion 13a in the impurity diffusion region (FIG. 3C).

Next, the P-side electrode 19 made of, for example, aluminum is formed by a known technique. However, as shown in FIG. 1A, the P-side electrode 19 extends from the impurity diffusion region 13 to the interlayer insulating film 17 via the interlayer insulating film portion 17x reaching the diffusion region. To form. Further, although not shown, an N-side electrode made of, for example, an Au alloy is formed as a first conductive-side electrode on the back surface of the base 11.

According to this manufacturing method, in the light emitting diode having the impurity diffusion region having a shallow diffusion depth, there is a fear of a short circuit between the base and the P-side electrode near the edge of the opening in the first insulating film. It is possible to easily manufacture a light emitting diode which has no light emitting area and has a sufficient light emitting area. Therefore, it becomes possible to manufacture a high-resolution light emitting diode array.

2. Second Embodiment Next, a light emitting diode of the second embodiment will be described. 4 (A) and 4 (B) are a plan view and a cross-sectional view taken along the line I-I used for the description.

In the light emitting diode of the second embodiment, the planar shape of the opening in the first insulating film 15 is a typical shape (here, a square shape). on the other hand,
Part of the interlayer insulating film 17 is in a state of protruding in a convex shape toward the opening 15 a side of the first insulating film 15. For convenience of description, the portion of the interlayer insulating film which is in a projecting shape is referred to as a “convex portion of the interlayer insulating film 17z”. This part 17z is shown in FIG.
Also in the plan view of (A), a diagonal pattern is added to emphasize. Then, the second conductive side electrode 19 is provided via the portion 17z of the interlayer insulating film that projects in a convex shape. In the case of the second embodiment, the protruding portion 17z of the interlayer insulating film surely covers the vicinity P of the edge of the opening 17a in the first insulating film. Therefore, the lateral diffusion amount at the time of forming the impurity diffusion region 13 is small, and the vicinity of the edge P remains as a base (that is, remains of the first conductivity type).
Even if it is, the second conductive side electrode 19 and the base 11
It is possible to prevent a short circuit between and.

The light emitting diode of the second embodiment is different from that of the first embodiment in the planar shape of the openings formed in the first insulating film 15 and the interlayer insulating film 17, respectively. The manufacturing method is the same as the manufacturing method in the first embodiment except for the points to note, and thus the description of the manufacturing method is omitted.

3. Third Embodiment Next, a light emitting diode of the third embodiment will be described. 5 (A) and 5 (B) are a plan view and a cross-sectional view taken along the line I-I used for the description.

In the first embodiment, a part of each of the opening 15a of the first insulating film 15 and the impurity diffusion region 13 that corresponds to the lead-out direction of the P-side electrode 19 has a convex shape along the lead-out direction. It was in an extended state.
On the other hand, in the third embodiment, the portions of the opening 15a of the insulating film 15 and the impurity diffusion region 13 which correspond to the lead-out direction of the P-side electrode 19 are generally expanded along the lead-out direction. is there. 1 in FIG.
The portion indicated by 5z corresponds to the overall expanded opening portion. At least a part of the interlayer insulating film 17 extends from above the first insulating film to the extended portion 1 of the impurity diffusion region.
It is provided so as to reach at least a part of 3a.
Also in the third embodiment, the interlayer insulating film portion 17x reaching the impurity diffusion region surely covers the vicinity P of the edge of the opening 15a in the first insulating film. Therefore, even when the amount of lateral diffusion during the formation of the impurity diffusion region 13 is small and the edge portion P remains as the base (that is, remains of the first conductivity type), the second conductivity-side electrode 1 is formed.
It is possible to prevent the short circuit between 9 and the base 11. Also in this case, since the impurity diffusion region is expanded in the extraction direction of the P-side electrode 19 and a part of the interlayer insulating film is provided on that part, even if a part of the interlayer insulating film is provided in the impurity diffusion region expansion, light emission It is possible to prevent the flat area of the part from being reduced.

4. Fourth Embodiment In the above-described first to third embodiments, the impurity diffusion region 1 is used.
A part of 3 was always exposed to the outside. However, as described with reference to FIGS. 6A and 6B, the entire surface of the opening 15a in the first insulating film 15 is covered with P
It may be configured to be covered with the interlayer insulating film 17 except the region used for connecting the side electrode 19 and the impurity diffusion region 13. However, in that case, the interlayer insulating film 17 is an insulating film having a predetermined film thickness that does not hinder the transmission and reception of light (here, since it is an example of a light emitting diode, it does not hinder the output of light). The light emitting diode of the fourth embodiment has a structure in which an interlayer insulating film 17 is interposed between the impurity diffusion region (light emitting portion) 13 and air. Since the refractive index of the insulating film is approximately between the refractive index of the semiconductor material and the refractive index of air, the light generated at the pn junction has a graded refractive index structure in the fourth embodiment. Will be output. Light emission from the light emitting diode when the opening 17a is partially exposed and when the entire surface of the opening 17a (excluding the extraction portion of the P-side electrode 19) is covered with the interlayer insulating film 17 The intensity distribution (near field pattern) is as shown in FIG. 7A for the former and as shown in FIG.
(B). As can be seen by comparing FIGS. 7A and 7B, in the light emitting diode in which a part of the opening 17a is exposed, the light emission intensity at the exposed portion (Q portion in FIG. 7A) is descend. On the other hand, opening 1
In the light emitting diode in which 7a is covered with the interlayer insulating film 17, the emission intensity does not decrease even in the portion corresponding to the portion Q in FIG. Therefore, it can be seen that the latter, that is, the fourth embodiment has a higher light extraction efficiency from the light emitting unit. According to the experience of the inventor of this application, the opening 1
It is known that when the entire surface of 7a is covered with the interlayer insulating film 17, the amount of light emission increases by 10% as compared with the case where it is not covered.

5. Fifth Embodiment In the above, an example of the light emitting diode including the interlayer insulating film 17 has been described. The main reason for providing the interlayer insulating film 17 is as follows. Since the first insulating film 15 has been subjected to a thermal diffusion process or the like, there is a high risk that film defects such as pinholes will exist. In such a case, if the second conductive side electrode 19 is directly formed on the first insulating film, the second conductive side electrode 19 and the base 11 are short-circuited via the pinhole. In order to avoid this and further improve reliability, the interlayer insulating film 17 is provided. However, when the first insulating film has excellent film quality, the interlayer insulating film 17 may not be used. In that case, according to the present invention, the second insulating film is provided in the vicinity P of the opening 17a in the first insulating film 17, or the inside of the opening 17a is covered with the second insulating film. The same effects as those of the above-described first to fourth embodiments can be obtained. FIG. 8 shows an example corresponding to the first embodiment, in which the second insulating film 31 is provided instead of the interlayer insulating film 17. That is, it is provided so as to extend from a portion above the extended portion 13a in the impurity diffusion region to at least a portion of the side wall of the opening 17a (the illustrated example shows an example up to the first insulating film 17). 2 and the P-side electrode 19
Is an example provided via the second insulating film 31.

When manufacturing a light emitting diode having the second insulating film 31, the interlayer insulating film forming thin film 17 in the manufacturing method described with reference to FIGS. 2 and 3.
In the step of forming y, a second insulating film forming thin film may be formed instead of the thin film 17y, and the thin film may be patterned into a desired shape (for example, the shape of FIG. 8).
Then, the P-side electrode 19 may be formed so as to pass over the second insulating film 31.

Further, the opening 1 in the first insulating film 15
5a entire surface (excluding the lead-out portion of the P-side electrode 19)
The structure in which is covered with the second insulating film 31 can also be obtained by a method according to the above-described manufacturing method.

In the above description, an example in which the invention according to this application is applied to a light emitting diode has been described, but the present invention is also applicable to a photodiode, a light emitting diode array, and a photodiode array. , And in each of those cases, a similar effect is obtained.

[0039]

As is apparent from the above description, according to the light emitting and receiving element of the present invention, at least a part of the interlayer insulating film (or the second insulating film) is removed from above the first insulating film. The second conductive side electrode is provided so as to reach a part of the impurity diffusion region through the side wall of the opening of the first insulating film, and further, the second conductive side electrode is provided on the interlayer insulating film part reaching the impurity diffusion region (or 2 on the insulating film). Therefore, the vicinity of the edge of the opening in the first insulating film is reliably covered with the interlayer insulating film portion (or the second insulating film) reaching the impurity diffusion region. Therefore, even when the amount of lateral diffusion during the formation of the impurity diffusion region is small and the vicinity of the edge remains as the base (that is, remains of the first conductivity type), the second conductive side electrode and the base 11 are separated from each other. It is possible to prevent short circuit. Therefore, a light emitting diode array having higher resolution can be constructed.

Further, according to the method of manufacturing a light emitting and receiving element of the present invention, the first insulating film having the opening of the predetermined expanded portion is formed on the lower ground of the first conductivity type, and the first insulating film is formed. The second conductivity type impurity is diffused into the base by a solid phase diffusion method using the film as a mask to form an impurity diffusion region having a region expanded by the expanded opening, and the first insulating film is formed. The interlayer insulating film (or the second insulating film) is covered so that a region from the top to at least a part of the extended portion of the impurity diffusion region is covered with the part of the interlayer insulating film (or the second insulating film).
Second insulating film) is formed, and the second conductive side electrode is formed via the interlayer insulating film portion reaching the impurity diffusion region (or the second insulating film). Therefore, the light emitting / receiving element according to the above invention can be easily manufactured without reducing the light emitting / receiving area.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a first embodiment.

FIG. 2 is a diagram (No. 1) showing an example of a method of manufacturing the light-emitting diode of the first embodiment.

FIG. 3 is a diagram (No. 2) showing an example of a method of manufacturing the light emitting diode according to the first embodiment.

FIG. 4 is an explanatory diagram of a second embodiment.

FIG. 5 is an explanatory diagram of a third embodiment.

FIG. 6 is an explanatory diagram (part 1) of the fourth embodiment.

FIG. 7 is an explanatory diagram (2) of the fourth embodiment.

FIG. 8 is an explanatory diagram of the fifth embodiment.

FIG. 9 is a diagram for explaining a problem.

[Explanation of symbols]

 11: Base made of compound semiconductor of first conductivity type 13: Impurity diffusion region of second conductivity type 13a: Extended portion in impurity diffusion region 15: First insulating film 15a: Opening portion 15x in first insulating film; Convex 15y: First insulating film forming thin film 15z: Overall expanded opening 17: Interlayer insulating film 17a: Opening in interlayer insulating film 17x: Up to impurity diffusion region Inter-layer insulating film portion 17y: Inter-layer insulating film forming thin film 17z: Inter-layer insulating film protruding portion 19: Second conductive side electrode 21: Diffusion source thin film 23: Annealing cap film 31: Second insulating film

Claims (8)

[Claims] 1. A diffusion mask having a second-conductivity-type impurity diffusion region on a base made of a first-conductivity-type compound semiconductor, and further having an opening on the base and at the time of forming the impurity-diffusion region. A first insulating film used as the insulating film, an interlayer insulating film provided on the first insulating film, and electrically connected to the impurity diffusion region and formed on the interlayer insulating film. In a light emitting / receiving element including a second conductive side electrode, at least a part of the interlayer insulating film is formed on the first insulating film through a side wall of an opening of the first insulating film and a part of the impurity diffusion region. The light emitting and receiving element, wherein the second conductive side electrode is provided via the interlayer insulating film portion reaching the impurity diffusion region. 2. The light emitting and receiving element according to claim 1, wherein the first insulating film has a part of a portion of the first insulating film that is in contact with the opening of the second conductive side electrode as compared with a desired opening. The first insulating film has an opening that is expanded in a convex shape or entirely along the extraction direction, and the impurity diffusion region is larger than the desired impurity diffusion region. The region is an impurity diffusion region extended by an amount, and at least a portion of the interlayer insulating film is provided over at least a portion of the extended portion of the impurity diffusion region and on the first insulating film. A light emitting and receiving element characterized by. 3. The light emitting and receiving device according to claim 1, wherein the interlayer insulating film covers the entire surface of the opening in the first insulating film with the second conductive side electrode and the impurity diffusion region. 1. A light emitting and receiving element, which is covered with the exception of a region used for connection, and which is an insulating film having a predetermined film thickness that does not hinder the transmission and reception of light. 4. The method for manufacturing the light emitting / receiving element according to claim 1, wherein the second conductive side electrode in the first insulating film is formed on the lower ground in comparison with a desired opening. Forming a first insulating film in which a portion corresponding to the drawing direction is partially convex or wholly having an opening expanded along the drawing direction; and using the first insulating film as a mask Diffusing a second conductivity type impurity into the base by a solid phase diffusion method, and forming an impurity diffusion region in which the region is expanded by the expanded opening as compared to the desired impurity diffusion region, A step of forming the interlayer insulating film so that a region extending from above the first insulating film to at least a part of an extended portion of the formed impurity diffusion region is covered with a part of the interlayer insulating film; Up to the impurity diffusion region Method of manufacturing optical element, which comprises a step of forming a second conductive side electrode by way of that interlayer insulating film portion above. 5. A diffusion mask having a second-conductivity-type impurity diffusion region on a base made of a first-conductivity-type compound semiconductor, further having an opening on the base and forming a diffusion mask when the impurity-diffusion region is formed. In a light receiving and emitting element comprising a first insulating film used as, and a second conductive side electrode which is electrically connected to the impurity diffusion region and is formed to extend over the first insulating film, A second insulating film provided so as to extend from a portion of the impurity diffusion region to at least a portion of the side wall of the opening, and the second conductive-side electrode is provided on the second insulating film. A light emitting / receiving element characterized by being provided as. 6. The light emitting and receiving element according to claim 5, wherein the first insulating film has a part of a portion of the first insulating film that is in contact with the opening of the second conductive side electrode as compared with a desired opening. The first insulating film has an opening that is expanded in a convex shape or entirely along the extraction direction, and the impurity diffusion region is larger than the desired impurity diffusion region. The second insulating film is provided as an impurity diffusion region having a region extended by the amount, and the second insulating film is provided over at least a part of the extended portion of the impurity diffusion region and on the first insulating film. The light emitting and receiving element. 7. The light emitting and receiving element according to claim 5, wherein the second insulating film covers the entire surface of the opening of the first insulating film, and the second conductive side electrode and the impurity diffusion region. A light emitting and receiving element, which is covered with the exception of a region used for connection with and is an insulating film having a predetermined film thickness that does not interfere with light transmission and reception. 8. The manufacturing of the light emitting / receiving element according to claim 5, wherein the second conductive side electrode in the first insulating film is provided on the lower ground in comparison with a desired opening. Forming a first insulating film in which a portion corresponding to the drawing direction is partially convex or wholly having an opening expanded along the drawing direction; and using the first insulating film as a mask Diffusing a second conductivity type impurity into the base by a solid phase diffusion method, and forming an impurity diffusion region in which the region is expanded by the expanded opening as compared to the desired impurity diffusion region, A step of forming a second insulating film over at least a part of the extended portion of the formed impurity diffusion region and over the first insulating film, and a second conductive film passing over the second insulating film. And a step of forming a side electrode. Method of manufacturing optical element to be.