JPH11195810A - Semiconductor light receiving element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-sensitivity semiconductor light receiving element, by decreasing light absorption at a portion other than the light absorption layer. SOLUTION: A Schottky electrode 20 is formed in part of a light incident surface 17 of a light absorption layer 14, and recessed and projected construction 18 is formed at a portion corresponding to a window portion 22 which is a part of the light incident surface side on a light absorption layer 14 where no Schottky electrode 20 is formed. Light passing the Schottky electrode 20 and light passing the window portion 22 without penetrating the Shottky electrode reach the light absorption layer 14. Light passing the window portion 22 is scattered by the recessed and projected construction 18, and the proportion of absorption to the depletion layer formed to the light absorption layer 14 near the Schottky electrode 20 becomes higher.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor light receiving device, and more particularly to, for example, a Schottky barrier type semiconductor light receiving device.

[0002]

2. Description of the Related Art Photodiodes include solar cells and CCDs.
For example, a Schottky barrier photodiode is used as a high-sensitivity photodiode for an optical sensor or the like.

Referring to FIG. 9, the structure of a conventional Schottky barrier photodiode will be described.

A Schottky barrier photodiode 1 shown in FIG. 9 comprises a substrate 2 made of n ⁺ -SiC and a light absorbing layer 3 made of n ^-- SiC formed on one main surface of the substrate 2.
An insulating film 4 made of SiO ₂ formed on the periphery of the light absorbing layer 3; a Schottky electrode 5 formed on the light absorbing layer 3 and the insulating film 4; And a back electrode 6 to be formed, and a lead-out electrode 7 is connected to the Schottky electrode 5.

In the Schottky barrier photodiode 1 shown in FIG. 9, light incident from the Schottky electrode 5 side is absorbed by the light absorbing layer 3 so that the light absorbing layer 3
Then, electron-hole pairs are generated, and a current flows by separating these electron-hole pairs. Therefore, of the incident light, the light absorbed by the light absorbing layer 3 is detected as a current.

Here, as the semiconductor used for the light absorbing layer 3, a semiconductor suitable for the wavelength of light to be detected is used.
That is, a semiconductor having a small band gap, for example, InP
Are used. On the other hand, a semiconductor having a large band gap, such as SiC or GaN, is suitable for light having a large energy such as ultraviolet light. If a semiconductor with a small band gap is used for light with high energy,
This is because it is not possible to detect only light having a large energy.

In general, the Schottky electrode 5 is made of a metal thin film of gold or the like having a thickness of about 0.2 μm, and the light on the insulating film 4 and the portion where the insulating film 4 is not formed is formed by vacuum evaporation or the like. It is formed on the absorption layer 3. Therefore,
The Schottky electrode 5 is formed on the entire surface of the light receiving section of the Schottky barrier photodiode 1.

[0008]

In the above prior art, the incident light is absorbed by the Schottky electrode 5 so that
There is a problem that the light reaching the light absorbing layer 3 decreases, and the sensitivity (the ratio of the generated current to the amount of incident light) decreases.
For example, when ultraviolet light or the like having a large absorption at the Schottky electrode 5 is incident light, even when silver having a small absorption of ultraviolet light is used as the Schottky electrode 5, about 30% of the incident light is reduced. Absorbed by the Schottky electrode 5,
This has caused a decrease in sensitivity. On the other hand, it is conceivable to reduce the light absorption of the Schottky electrode 5 by reducing the thickness of the Schottky electrode 5, but when the Schottky electrode 5 is thinned, the resistance of the Schottky electrode 5 increases. The electric field in the light-absorbing layer becomes non-uniform, which again causes a reduction in sensitivity.

Therefore, a main object of the present invention is to provide a semiconductor light receiving element having high sensitivity by reducing light absorption in portions other than the light absorbing layer.

[0010]

According to a first aspect of the present invention, there is provided a semiconductor light receiving element comprising: a light absorbing layer made of a semiconductor; and a junction forming layer provided on a light incident surface of the light absorbing layer. A semiconductor light receiving element for detecting light incident on a light receiving portion by a light absorbing layer, wherein a part of a light incident surface of the light absorbing layer is provided with a portion where no bonding formation layer is provided, and no bonding formation layer is provided. In a portion, light scattering means is provided on the light incident surface of the light absorbing layer.

According to a second aspect of the present invention, there is provided the semiconductor light receiving element according to the first aspect, wherein the light scattering means comprises an uneven structure provided on the light incident surface of the light absorbing layer. It is.

According to a third aspect of the present invention, in the semiconductor light receiving element according to the first aspect, the light absorbing layer is made of a crystalline semiconductor, and the light scattering means is provided on the light incident surface side of the light absorbing layer. It is characterized by comprising an amorphous region.

According to a fourth aspect of the present invention, in the semiconductor light receiving element according to the third aspect, an interface between the amorphous region and the light absorbing layer has an uneven shape.

According to a fifth aspect of the present invention, in the semiconductor light receiving element according to any one of the first to fourth aspects, the junction forming layer includes a window, and the light scattering means is provided on the window of the light absorbing layer. It is formed in the corresponding part.

According to a sixth aspect of the present invention, in the semiconductor light receiving element according to any one of the first to fifth aspects, an area of a portion of the light receiving portion where the junction forming layer is not formed is smaller than that of the light receiving portion. It is 40% or less of the area.

In the semiconductor light receiving device according to the first aspect, a junction forming layer (a layer formed on the light absorbing layer for forming a junction; in a Schottky barrier photodiode, a Schottky electrode and a pn photo Diode and pi
The n-photodiode is a semiconductor layer of a conductivity type different from the light absorption layer. ) Is formed only on a part of the light incident surface of the light absorbing layer (one main surface on the light incident side of the light absorbing layer), so that the absorption of incident light in the junction forming layer, that is, the loss of incident light is reduced. .

Further, since the incident light is scattered by the light scattering means provided at the portion where the junction forming layer is not provided, the incident light passing through the portion where the junction forming layer is not provided will be incident. The ratio of absorption in the light absorption layer and absorption in the depletion layer formed in the light absorption layer near the junction forming layer is increased. Therefore, a semiconductor light receiving element having higher sensitivity than the conventional semiconductor light receiving element can be obtained.

In the semiconductor light receiving device according to the second aspect, the light scattering means has an uneven structure provided on the light incident surface of the light absorbing layer, and the light incident on the semiconductor light receiving device is scattered by the uneven structure so that the sensitivity is increased. Will be higher.

In the semiconductor light receiving device according to the third aspect, the light scattering means comprises an amorphous region provided on the light incident surface side of the light absorbing layer, and the light incident on the semiconductor light receiving device is scattered by the amorphous region. , The sensitivity increases.

In the semiconductor light receiving device according to the fourth aspect, the interface between the amorphous region and the light absorbing layer has an uneven shape,
The light incident on the semiconductor light receiving element is scattered by the amorphous region and the interface between the amorphous region and the light absorbing layer, so that the ratio of the incident light absorbed by the depletion layer in the light absorbing layer increases, and the sensitivity is further increased. Get higher.

In the semiconductor light receiving device according to the fifth aspect, the junction forming layer includes the window, and the light passing through the window is scattered by the light scattering means and is absorbed by the depletion layer around the window. Is improved.

According to the semiconductor light receiving element of the present invention, when the area of the light receiving portion where the junction forming layer is not formed is too large, the light absorbed in the depletion layer is reduced or the junction forming layer is reduced. In view of the decrease in sensitivity due to an increase in the resistance of the light receiving portion, the area of the light receiving portion where the junction forming layer is not formed is set to 40% or less of the area of the light receiving portion.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

Referring to FIG. 1, one embodiment in which the present invention is applied to a photodiode will be described. This embodiment particularly relates to a Schottky barrier type photodiode using an uneven structure on the surface of a light absorbing layer as light scattering means. FIG. 1 (a) is a plan view and FIG. 1 (b).
FIG. 2 is an end view in the XY direction of FIG.

The Schottky barrier photodiode 10 shown in FIG. 1 is a substrate 1 made of, for example, n ⁺ -SiC.
2, a light absorbing layer 14 made of n ⁻ -SiC formed on one main surface of the substrate 12, an insulating film 16 made of SiO ₂ formed in a peripheral portion on the light absorbing layer 14, and And a back electrode 24 formed on the other main surface of the substrate 12, and a lead connected to the Schottky electrode 20. And an electrode 26.

Further, the Schottky electrode 20 is disposed at the interval W1.
And a rectangular window portion 22 having a width W2 formed in parallel with the above, and a concavo-convex structure 18 is formed in a portion of the light absorbing layer 14 corresponding to the window portion 22.

Here, the light receiving section 28 shown in FIG.
Includes a contact portion between the light absorbing layer 14 and the Schottky electrode 20 and a portion where the window 22 is formed, and the light incident on the light receiving portion 28 is detected as a current.

The substrate 12 made of n ⁺ -SiC is
For example, a thickness of 300 μm and an impurity concentration of 1 × 10 ¹⁹ cm
^The light absorbing layer 14 made of ⁻³ , n ⁻ —SiC has a thickness of, for example, 10 μm and an impurity concentration of 1 × 10 ¹⁶ cm ⁻³ or less. The uneven structure 18 is formed by minute unevenness of about 0.1 μm or less formed on the surface of the light absorbing layer 14, and the Schottky electrode 20, the back electrode 24, and the extraction electrode 26 are made of silver, nickel, and gold, respectively. And the like.

In the Schottky barrier type photodiode 10 shown in FIG. 1, of the light incident on the photodiode, the light that passes through the Schottky electrode 20 and reaches the light absorbing layer 14 does not pass through the Schottky electrode 20. Since the light reaching the light absorbing layer 14 forms an electron-hole pair in the light absorbing layer 14, incident light which is absorbed by the Schottky electrode 20 and becomes a loss is smaller than that of the conventional photodiode, and the sensitivity is improved. I do.

Furthermore, the incident light that reaches the light absorbing layer 14 without passing through the Schottky electrode 20 is scattered by the uneven structure 18 formed on a part of the light absorbing layer 14, as described below. The sensitivity is further improved.

FIG. 2 is an illustrative view showing that light incident on the Schottky barrier type photodiode 10 is scattered by the uneven structure 18. Irrespective of whether light is vertically incident on the concavo-convex structure as shown in FIG. 2A or obliquely as shown in FIG. The light is scattered and easily absorbed by the depletion layer 30 formed in the light absorption layer 14 near the Schottky electrode 20. Electron-hole pairs generated by light absorbed by the depletion layer 30 are quickly separated without recombination or the like, so that sensitivity is improved. The depletion layer 30
Varies depending on the impurity concentration of the light absorption layer 14, the bias voltage, and the like, but the incident light is scattered by the uneven structure 18 and the ratio of absorption by the depletion layer is still high.

FIG. 3 is a graph showing the relationship between the ratio of the area of the window 22 to the area of the light receiving section 28 and the sensitivity in the embodiment of FIG. The area ratio of the window 22 was changed by changing the interval W1 and the width W2 of the window 22. In the graph, the case where the value on the horizontal axis is 0 corresponds to the Schottky barrier photodiode having the conventional structure.

As shown in FIG. 3, when the area of the window portion 22 is set to be approximately 40% or less of the area of the light receiving portion 28, the sensitivity becomes higher than that of the conventional structure. When the area of the window 22 is approximately 12% or more and 29% or less of the area of the light receiving unit 28, the sensitivity is 5% or more higher than that of the conventional structure. Further, the sensitivity is maximized when the area of the window 22 is approximately 20% of the area of the light receiving portion 28, and the sensitivity is improved by approximately 6% as compared with the conventional structure. The window 2 occupying the area of the light receiving unit 28
The relationship between the area and the sensitivity varies depending on the shape of the window 22, the type of the semiconductor material used for the light absorbing layer 14, the shape of the concavo-convex structure 18, and the like. FIG. It only shows.

Referring to FIG. 4, an example of a method of manufacturing the Schottky barrier photodiode 10 shown in FIG. 1 will be described.

First, as shown in FIG.
On a substrate 12 made of n ⁺ -SiC having an impurity concentration of 1 × 10 ¹⁹ cm ^{-3 and} a light absorbing layer 14 made of undoped n ^-- SiC having an impurity concentration of 1 × 10 ¹⁵ cm ^{-3 having} a thickness of 10 μm.
Then, an insulating film 16 made of SiO _{2 is} formed on the light absorbing layer 14 to a thickness of 0.2 μm by sputtering or the like. Here, the substrate 12 is [11] from the (0001) Si plane of 6H—SiC.
The substrate was turned off three times in the [-20] direction.

Next, as shown in FIG. 4B, a part of the insulating film 16 is selectively removed by a photolithography step and an etching step. At this time, the portion where the insulating film 16 is removed is a portion where the uneven structure 18 is formed. For example, in the embodiment of FIG. 1, the portion of the insulating film 16 corresponding to the uneven structure 18 is removed in a strip shape.

Subsequently, using the insulating film 16 as a mask, RI
E method (Reactive Ion Etching method), light absorption layer 1
4 is etched by about 0.1 μm. The reaction conditions include, for example, C gas flow rate of 70 sccm as a reactive gas.
Etching may be performed for a predetermined time under the conditions of a reaction pressure of 20 Pa and a discharge output of 200 W using F ₄ and O ₂ gas at a flow rate of 80 sccm. As a result, as shown in FIG. 4C, the concavo-convex structure 18 is formed on a part of the light absorption layer 14 corresponding to a part where the insulating film 16 is not formed.

Further, as shown in FIG. 4D, the insulating film 16 where the Schottky electrode 20 is to be formed is selectively removed by a photolithography process and an etching process.

Next, as shown in FIG. 4E, a part of the light absorbing layer 14 on which the uneven structure is not formed on the light incident surface 17 and a part of the insulating film 16 are made of Schottky made of silver. After the electrodes 20 are selectively formed, a back electrode 24 made of nickel is formed on the back surface of the substrate 12, and a lead electrode 26 is connected to the Schottky electrode 20 (not shown). The portion where the Schottky electrode 20 is not formed on the light absorbing layer 14 becomes the window 22. As a method of selectively forming the Schottky electrode, silver may be deposited on the patterned photoresist, and then the photoresist may be lifted off. The thickness of the Schottky electrode is
Considering the increase in light absorption by increasing the thickness of the Schottky electrode and the increase in resistance
Preferably, the thickness is about 0.2 μm.

Thus, the Schottky barrier photodiode 10 is formed. In the Schottky barrier photodiode 10 of this embodiment, the light absorbing layer 14 has a band gap of 2.9 eV (300 K) of 6H-
A photodiode using SiC and having a sensitivity peak at 270 nm is obtained. Such a photodiode is used for a flame sensor, a fire alarm, a sunburn alarm, and the like. The present invention enhances sensitivity by reducing light absorption in areas other than the light-absorbing layer. As in this embodiment, a photo-detector having a sensitivity peak in an ultraviolet light region where light absorption in a Schottky electrode is increased. Particularly suitable for diodes.

Referring to FIG. 5, another embodiment of the present invention will be described. This embodiment particularly relates to a Schottky barrier type photodiode using an amorphous region as a light scattering means. FIG. 5A is a plan view, and FIG. It is an end elevation in the Y direction.

The Schottky barrier photodiode 10a shown in FIG. 5 has an amorphous region 32 on the light absorption layer 14 in a portion corresponding to the window 22, as compared with the Schottky barrier photodiode 10 of FIG. The interface between the light absorbing layer 14 and the amorphous region 32 is different in that it has an uneven shape. However, the other structures are the same, and duplicate description will be omitted. The amorphous region 32 is, for example, amorphous SiC.

In the Schottky barrier photodiode 10a shown in FIG. 5, similarly to the Schottky barrier photodiode 10 shown in FIG. 1, incident light which is absorbed by the Schottky electrode 20 and becomes a loss is smaller than that of the conventional photodiode. Less, sensitivity is improved.

Further, incident light that does not pass through the Schottky electrode 20 and reaches the light absorbing layer 14 is scattered by the amorphous region 32 formed adjacent to a part of the light absorbing layer 14, so that the sensitivity is further improved. improves.

FIG. 6 is an illustrative view showing that light incident on the Schottky barrier photodiode 10 a is scattered by the amorphous region 32. Since the amorphous region 32 has a non-uniform structure, light incident thereon is scattered in the amorphous region 32. Further, since the interface between the light absorbing layer and the amorphous region 32 has an uneven shape, light is also scattered at this interface. Therefore, the incident light is scattered regardless of whether the light is vertically incident on the uneven structure as shown in FIG. 6A or the light is obliquely incident as shown in FIG. 6B. The light is easily absorbed by the depletion layer 30 formed in the light absorption layer 14 near the Schottky electrode 20. Electron-hole pairs generated by light absorption in the depletion layer 30 are quickly separated without recombination, so that sensitivity is improved.

FIG. 7 shows a light receiving section 2 in this embodiment.
8 is a graph showing the relationship between the ratio of the area of the window portion 22 to the area of No. 8 and the sensitivity. The ratio of the area of the window part 22 is
2 by changing the interval W1 and the width W2. In the graph, the case where the value on the horizontal axis is 0 corresponds to the Schottky barrier photodiode having the conventional structure.

As shown in FIG. 7, when the area of the window 22 is set to approximately 40% or less of the area of the light receiving section 28, the sensitivity is higher than that of the conventional structure. When the area of the window 22 is approximately 13% or more and 27% or less of the area of the light receiving unit 28, the sensitivity is 5% or more higher than that of the conventional structure. Further, the sensitivity is maximized when the area of the window 22 is approximately 20% of the area of the light receiving portion 28, and the sensitivity is improved by approximately 6% as compared with the conventional structure. FIG. 7 shows only an example of the change in sensitivity as in FIG.

Referring to FIG. 8, an example of a method for manufacturing the Schottky barrier photodiode 10a shown in FIG. 5 will be described.

First, as shown in FIG.
On a substrate 12 made of n ⁺ -SiC having an impurity concentration of 1 × 10 ¹⁹ cm ^{-3 and} a light absorbing layer 14 made of undoped n ^-- SiC having an impurity concentration of 1 × 10 ¹⁵ cm ^{-3 having} a thickness of 10 μm.
Then, an insulating film 16 made of SiO _{2 is} formed on the light absorbing layer 14 to a thickness of 0.2 μm by sputtering or the like. Here, the substrate 12 is [11] from the (0001) Si plane of 6H—SiC.
The substrate was turned off three times in the [-20] direction.

Next, as shown in FIG. 8B, a part of the insulating film 16 is selectively removed by a photolithography step and an etching step. At this time, since the amorphous region 32 is formed in the portion where the insulating film 16 is removed, for example, in the embodiment of FIG. 5, the portion of the insulating film 16 corresponding to the amorphous region 32 is removed in a strip shape. You.

Subsequently, as shown in FIG. 8C, ions of hydrogen, argon, nitrogen, oxygen and the like are applied to the light absorbing layer 14 to a depth of 0.2 to 0.3 μm using the insulating film 16 as a mask. By ion implantation, a part of the light absorption layer 14 corresponding to a part where the insulating film 16 is not formed is made amorphous, and an amorphous region 32 made of amorphous SiC is formed. At this time, since the depth of the implanted ions is not constant, the interface between the amorphous region 32 and the light absorbing layer does not become a smooth plane, and uneven unevenness is formed.

Further, as shown in FIG. 8D, a portion of the insulating film 16 where the Schottky electrode 20 is to be formed is selectively removed by a photolithography process and an etching process.

Next, as shown in FIG. 8E, a Schottky electrode 20 made of silver is selectively formed on a part of the light absorbing layer 14 on the light incident surface 17 and a part on the insulating film 16. After that, the back surface electrode 24 made of nickel is
Is formed, and a lead electrode 26 is connected to the Schottky electrode 20 (not shown). The portion where the Schottky electrode 20 is not formed on the light absorbing layer 14 becomes the window 22. The method of forming the Schottky electrode 20 and the film thickness are the same as those described with reference to FIG.

Thus, the Schottky barrier photodiode 10a is formed.

As described above, the embodiments of the present invention have been described by way of examples. However, the present invention is not limited to the above embodiments, and may be embodied in various other forms based on the technical idea of the present invention. be able to.

For example, in the above embodiment, the Schottky junction type photodiode has been described.
Even in photodiodes and pn photodiodes,
The present invention can be implemented. That is, in the case of a pin photodiode or the like, instead of selectively forming the Schottky electrode 20 in FIG. 4E or FIG. 8E, a conductive semiconductor layer different from the light absorption layer is selectively formed. It may be formed. In both the pin photodiode and the Schottky barrier diode, since the junction forming layer is formed only in a part of the light receiving portion, light loss in the junction forming layer is reduced, and the sensitivity is improved. Note that as a method for selectively forming a semiconductor layer having a conductivity type different from that of the light absorption layer on a part of the light absorption layer, a method of injecting a dopant using SiO ₂ or the like as a mask may be used.

In the above embodiment, the light absorption layer is made of n
^Although -SiC is used, an intrinsic or p-type semiconductor may be used, or another semiconductor material such as Si, GaN, or InP may be used.

Further, in the above-described embodiment, silver having low absorption of ultraviolet light is used as the Schottky electrode. However, any metal that forms a Schottky junction with the light absorbing layer may be appropriately used in accordance with the wavelength of light to be detected. , Gold, molybdenum, titanium, tungsten and the like can be selected and used.

In the above embodiment, 6H-SiC is used as the light absorbing layer, but another semiconductor material may be used. For example, the band gap is 2.2 eV (300K)
Wavelength of 520 by using 3C-SiC
A photodiode corresponding to light of nm or less can be formed,
It can be used for fire alarms, flame sensors, blue sensors, etc. Further, the band gap is 3.2 eV (30
By using 4H-SiC (0K), a photodiode corresponding to light having a wavelength of 340 nm or less can be formed, and can be used for an ultraviolet light quantity monitor, a sunburn alarm, and the like.

Further, in the above-described embodiment, the case where a Schottky electrode having a window portion is formed as a form in which a junction is formed on a part of the light absorbing layer on the light incident surface side is described. A Schottky electrode having a comb shape or the like may be used, and the shape and number of windows may be any. Note that the closer the boundary between the portion where the Schottky electrode is not formed and the portion where the Schottky electrode is formed, the higher the ratio of incident light to the depletion layer due to scattering, and thus the Schottky electrode is not formed. It is advantageous to use an electrode structure in which the boundary between the portion and the formed portion is long. Therefore, the sensitivity is higher when a large number of small windows such as a square or a circle are formed.

[0061]

According to the present invention, a semiconductor photodetector with high sensitivity can be obtained by reducing light absorption in portions other than the light absorbing layer.

[Brief description of the drawings]

FIG. 1 is an illustrative view showing one embodiment of the present invention;
(A) is a plan view, (b) is an end view.

FIG. 2 is an illustrative view showing a function of a concave-convex structure in the embodiment of FIG. 1; FIG. 2 (a) is an illustrative view showing a function for vertically incident light, and FIG. 2 (b) is an illustrative view showing a function of obliquely incident light; .

FIG. 3 is a graph showing a relationship between a ratio of an area of a window portion to an area of a light receiving portion and sensitivity in the embodiment of FIG. 1;

FIG. 4 is a process chart showing an example of a manufacturing process of the embodiment of FIG. 1;

FIG. 5 is an illustrative view showing another embodiment of the present invention;
(A) is a plan view, (b) is an end view.

6A is an illustrative view showing a function of an amorphous region in the embodiment of FIG. 5, wherein FIG. 6A is an illustrative view showing a function for vertically incident light, and FIG. 6B is an illustrative view showing a function for obliquely incident light; .

FIG. 7 is a graph showing the relationship between the ratio of the area of the window 22 to the area of the light receiving unit in this embodiment and the sensitivity in the embodiment of FIG. 5;

FIG. 8 is a process chart showing an example of a manufacturing process of the embodiment of FIG. 5;

FIG. 9 is an illustrative view showing one example of a conventional photodiode;

[Explanation of symbols]

Reference Signs List 10 and 10a Schottky barrier photodiode 12 Substrate 14 Light absorbing layer 16 Insulating film 17 Light incident surface 18 Uneven structure 20 Schottky electrode 22 Window 24 Back electrode 28 Light receiving unit 30 Depletion layer 32 Amorphous region

Claims (6)

[Claims] 1. A semiconductor light receiving element comprising: a light absorbing layer made of a semiconductor; and a junction forming layer provided on a light incident surface of the light absorbing layer, wherein the light absorbing layer detects light incident on a light receiving portion. A part where the bonding layer is not provided on a part of the light incident surface of the light absorbing layer, and a light scattering unit is provided on the light incident surface of the light absorbing layer in a part where the bonding layer is not provided. A semiconductor light receiving element characterized by the above-mentioned. 2. The semiconductor light receiving device according to claim 1, wherein said light scattering means has an uneven structure provided on a light incident surface of said light absorbing layer. 3. The light-absorbing layer is made of a crystalline semiconductor.
2. The semiconductor light receiving device according to claim 1, wherein said light scattering means comprises an amorphous region provided on a light incident surface side of said light absorbing layer. 4. The semiconductor light receiving device according to claim 3, wherein an interface between the amorphous region and the light absorbing layer has an uneven shape. 5. The semiconductor light receiving device according to claim 1, wherein said junction forming layer includes a window, and said light scattering means is formed in a portion of said light absorbing layer corresponding to said window. element. 6. The area of the light receiving section where the junction forming layer is not formed is 40% of the area of the light receiving section.
The semiconductor light-receiving element according to claim 1, wherein: