JPH0548072A - Semiconductor element - Google Patents

Abstract

PURPOSE:To improve quality and lengthen life by stacking a semiconductor substrate body consisting of Si, a semiconductor layer consisting of single crystal InP, and a semiconductor layer for buffer, with the semiconductor layer for buffer between. CONSTITUTION:Si-CMOS 2 and a semiconductor laser 3 are integrated on an Si substrate 1. At this time, a semiconductor laser 3 is made on the InP layer 8 on the first buffer layer 4 consisting of GaAs and the second buffer layer 5 consisting of InGaAs. The active layer 9 of this semiconductor laser 3 consists of multiple quantum well, and a barrier layer consists of InGaAsP of 10nm, and a well layer InGaAs of 7.5nm. And the number of well layers is made six. The oscillated wavelength at this time is 1.54mum. Next, a ridge 6mum wide is formed by the selective etching by chemical etching. Furthermore, a mirror face is made by dry etching. It is made a laser 300mum in resonance length, using nitride silicon as an insulating film 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a semiconductor substrate formed by laminating a single crystal compound semiconductor layer on a semiconductor substrate body made of Si, and a semiconductor element or Si electronic device in which a Si electronic circuit and a semiconductor laser are integrated. The present invention relates to a semiconductor device in which a circuit, a semiconductor laser, and a light receiver are integrated.

[0002]

2. Description of the Related Art Conventionally, a semiconductor device has been proposed in which a compound semiconductor layer made of III-V group of the periodic table of elements is laminated on a semiconductor substrate body made of single crystal Si. Among the device applications that have been performed so far, the fabrication of semiconductor lasers is an important technology that enables optical and electronic fusion of optical devices made of III-V compound semiconductors and Si-LSI. GaAs materials have been mainly used in the fabrication of semiconductor lasers on Si substrates, which have been studied so far, but these semiconductor lasers have a fatal drawback.
That is, it has a short life due to deterioration after several hours of operation. It has been clarified that this is due to the high density of dislocations and residual stress existing in the GaAs film on the Si substrate. Therefore, an optical / electronic fusion device in which the Si electronic circuit and the GaAs semiconductor laser are integrated has not yet been realized. On the other hand, applied materials are considered to be applied to semiconductor lasers in materials other than GaAs.
Physics Letter, Volume 53 (1988), 238
Page 9 [Appl. Phys. Lett., 53 (1988) p. 23.
89], and the InP-based 1.3 μm semiconductor laser. What is remarkable about this semiconductor laser is that it does not have the rapid deterioration as seen in GaAs semiconductor lasers. The material dependence of the lifetime of the semiconductor laser is not limited to the Si substrate, but is also applied to ordinary semiconductor lasers. However, this InP
The system semiconductor laser is not abrupt, but the driving current is gradually increased and the semiconductor element is deteriorated. Therefore, the problem still exists from a practical level.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems in the prior art,
Using a semiconductor substrate formed by laminating a single crystal compound semiconductor layer on a semiconductor substrate body made of single crystal Si, Si
An object of the present invention is to provide a semiconductor laser that operates stably for a long time in a semiconductor element configured by integrating an electronic circuit and a semiconductor laser, or a light receiver.

[0004]

In order to achieve the above-mentioned object of the present invention, a semiconductor layer made of single crystal InP is laminated on a semiconductor substrate body made of Si, and a Si electronic circuit and a semiconductor laser or Si electron are stacked. When a circuit, a semiconductor laser, and a light receiver are integrated to form a semiconductor element, a semiconductor substrate body made of Si and a semiconductor layer made of single crystal InP are laminated with a buffer semiconductor layer interposed therebetween, whereby The quality of a semiconductor layer made of crystalline InP is improved to realize a long-life semiconductor laser that oscillates long-wavelength light having a wavelength of 1.4 μm or more.

[0005]

Embodiments of the present invention will be described below in more detail with reference to the drawings. (Embodiment 1) FIG. 1 is a schematic diagram showing an example of the configuration of a semiconductor device manufactured in this embodiment. In the figure, S
A Si-CMOS 2 and a semiconductor laser 3 are integrated on an i substrate 1. At this time, the semiconductor laser 3 is formed on the first buffer layer 4 made of GaAs and the InP layer 8 on the second buffer layer 5 made of InGaAs. The active layer 9 of this semiconductor laser 3 is composed of multiple quantum wells, and the barrier layer is an InGaAsP (wavelength: 1.3 μm) of 10 nm.
m), the well layer is 7.5 nm of InGaAs (wavelength 1.65μ).
m). The guide layer is also 100 nm InGaAs.
P (wavelength 1.3 μm). The total number of well layers was 6. The oscillation wavelength at this time was 1.54 μm. Next, a ridge 6 having a width of 6 μm was formed by selective etching by chemical etching. Further, a mirror surface was formed by dry etching. As the insulating film 10, silicon nitride was used, and a laser having a resonance length of 300 μm was used. The manufactured semiconductor laser has p and n electrodes 11, 12
The structure is such that The manufactured semiconductor laser 3 on the Si substrate 1 oscillated at a threshold value of 55 mA at room temperature. Further, in the semiconductor laser 3 operating at room temperature with a constant output of 2 mW, the driving current did not change and the deterioration was not observed for 1500 hours or more.
Further, the semiconductor laser drive circuit composed of the integrated Si-CMOS 2 was able to operate at a high speed of 1 GHz without any problem. Needless to say, the semiconductor laser of the present invention is not limited to the above-mentioned embodiments, and various structures of the ridge width and the active layer can be produced as long as they oscillate a long wavelength of 1.4 μm or more. Also, an embedded structure can be manufactured.

(Embodiment 2) FIG. 2 shows an example of the structure of a semiconductor device manufactured in this embodiment. As in Example 1, S
On the Si substrate 1 in which the i-CMOS 2 and the semiconductor laser 3 are integrated, a photodetector 7 having an InGaAs light receiving layer 13 is integrated. However, the semiconductor laser 3 of this embodiment has a DH structure having an InGaAsP bulk active layer 9,
The oscillation wavelength was 1.4 μm. This semiconductor laser 3
Oscillated at a threshold value of 57 mA at room temperature. Further, in the semiconductor laser 3 operating at room temperature with a constant output of 2 mW, the driving current did not change and the deterioration was not observed for 1200 hours or more. Like the semiconductor laser 3, the integrated photodetector 7 has an In formed on the first GaAs buffer layer 4 and the second InGaAs buffer layer 5.
It is formed on the P layer 8. With the semiconductor device of this embodiment, a semiconductor device capable of obtaining a light emission signal of the semiconductor laser modulated by the input light to the light receiver 7 could be realized.

[0007]

The semiconductor device of the present invention is constituted by laminating a semiconductor layer of single crystal InP on a Si substrate on which an electronic circuit made of Si is mounted. In this case, a semiconductor layer for buffer is interposed. By stacking single crystal InP semiconductor layers,
The quality of the single crystal InP semiconductor layer can be improved. Higher quality specifically means reduction of dislocation density and reduction of residual stress in the semiconductor element. Further, by setting the oscillation wavelength of the integrated semiconductor laser to be 1.4 μm or more, a long-life semiconductor laser is realized. This is effective in suppressing the growth of dark line defects during the operation of the semiconductor laser, and can extend the life of the semiconductor laser. Further, since the long wavelength band of the above-mentioned semiconductor laser matches the low loss wavelength band of the optical fiber, it is promising as an optical element for transmission. Further, the semiconductor laser having the above structure enables not only an optical / electronic fusion circuit by fusion with Si-LSI but also an optical integrated circuit by fusion with a silica-based waveguide. Realization of these integrated circuits is not limited to the possibility of miniaturization and high performance of conventional systems,
It is expected to become an important key device for future optical switching and the realization of optical computers.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an example of a configuration of a semiconductor device exemplified in a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing an example of a configuration of a semiconductor device exemplified in a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Si substrate 2 ... Si-CMOS 3 ... Semiconductor laser 4 ... 1st GaAs buffer layer 5 ... 2nd InGaAs buffer layer 6 ... Ridge 7 ... Photoreceiver 8 ... InP layer 9 ... Active layer 10 ... Insulating layer 11 ... p electrode 12 ... n electrode 13 ... light receiving layer 14, 15 ... electrode

Claims (3)

[Claims] 1. A semiconductor laser which oscillates long-wavelength light having a wavelength of 1.4 μm or more on a silicon (Si) substrate through an electronic circuit made of Si and at least one kind of single crystal compound semiconductor layer. A semiconductor device characterized by being integrated. 2. A semiconductor laser which oscillates long-wavelength light having a wavelength of 1.4 μm or more on a silicon (Si) substrate through an electronic circuit made of Si and at least one or more kinds of single crystal compound semiconductor layers. A semiconductor device characterized by integrating a light receiver. 3. The single crystal compound semiconductor layer according to claim 1 or 2, wherein the single crystal compound semiconductor layer is laminated on a silicon (Si) substrate.
A semiconductor device comprising a single crystal compound semiconductor layer composed of an InP layer, which is laminated with a first buffer layer composed of GaAs and a second buffer layer composed of InGaAs interposed therebetween.