JPS61108187A - Semiconductor photoelectronic device - Google Patents

Abstract

PURPOSE:To integrate a light-emitting element, a light-receiving element and an electronic element on a single substrate and to obtain an photoelectronic device with high utility, by selectively utilizing the upper or lower face of the Si single-crystal substrate and by superposing thereon an amorphous insulation film, a thin film of a compound semiconductor and multilayer thin film of said compound semiconductor. CONSTITUTION:An SiO2 film 2 on an N type Si substrate 1 is provided, on the surface thereof, with rectangular stripe grooves with a depth of 10-10<5>Angstrom and a width of 0.1-10mum by means of etching. Amorphous or polycrystalline N type GaAs 3 is then deposited thereon by the vapor growth, and is heated so that it is rearranged along the grooves and that single crystal is caused to grow. Subsequently, an N type AlGaAs layer 4, an AlGaAS active layer 5, a P type AlGaAs layer 6 and a P type GaAs layer 8 are epitaxially deposited to form a laser diode. An N<+> layer 10 is provided in the P<+> layer 9 of the substrate 1 to form an NPN transistor. These are provided with protective films 11 and 12, electrodes 8, 13 and 14 and wiring 15, respectively. According to this construction, the intensity of laser beams can be controlled with the base current in the transistor. Further, it is also possible to integrate a laser element, a light-receiving element and a driving element on one face while integrating a driving element and a signal processing arithmatical element on the opposite face.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a substrate structure and a mechanical part of a semiconductor optoelectronic device.

[Conventional technology]

Taking advantage of the features of light, such as its high speed, multiplicity, and precision, optical technology is beginning to be introduced in place of electronic technology for information transmission and processing. Typical examples include long-distance optical communication technology that uses optical fibers and laser light, and audio and image reproduction technology that combines optical disks and semiconductor lasers.

In these optical systems, a light-emitting element that emits laser light or the like, a light-receiving element that converts a transmitted optical signal into an electrical signal, and an electronic device that drives these light-emitting and light-receiving elements are the heart of the optical system.

These optical elements and electronic devices are beginning to be integrated in order to make systems smaller, more sophisticated, and faster. In other words, semiconductor lasers (LDs) and photodiodes (PDs)
) and a field effect transistor (FET, ) are fabricated on the same semiconductor substrate surface, and L D+F D is driven by F]1liT. For example, as shown in IEICE Proceedings 4-28, Lecture No. 974, an LD composed of an indium-gallium-arsenic-synphorus compound semiconductor and an indium phosphide compound semiconductor are mounted on an indium phosphide compound semiconductor substrate. An FET was fabricated and the laser beam was modulated by FF1T.

Also, as in the same collection of papers 4-24, lecture number 970, a photodiode and a FET are fabricated on the same substrate surface. Semiconductor substrates used in such semiconductor optoelectronic devices have conventionally been indium phosphide (P) substrates and gallium arsenide (Ga) substrates.
As) substrates are mainly used. It is easy to fabricate semiconductor laser devices with good characteristics on these substrates.

On the other hand, some semiconductor optoelectronic devices are manufactured by growing compound semiconductors on silicon substrates. In 1985 IEICE Conference Proceedings 2-17, Lecture No. 255, germanium was epitaxially grown on a silicon single crystal substrate, gallium arsenide was epitaxially grown on the surface of the silicon single crystal substrate, and FE'T was applied to the gallium arsenide. I'm making it. Also, The 16th Con, ference
on Bolicl 5tate Devicesan
d Materials 1984, lecture number C11, similarly to the previous example, gallium arsenide was grown on a silicon single crystal substrate via germanium, and a laser diode was created on the surface to emit pulses.

[Problems that the invention aims to solve]

However, the above-mentioned conventional technology has the following problems. In other words, it is not possible to increase the driving voltage for electronic devices such as F'FiT using a compound semiconductor as a substrate, and M:rs (
Metal-■nsrbrator-8emicond
In addition to problems that affect the characteristics, such as the large number of levels at the interface, making it difficult to control the threshold voltage, low hole mobility, and too wide a forbidden band width, there are also problems such as poor stability and reliability. There is a problem. Further, the compound semiconductor substrate itself has problems such as poor crystallinity, high substrate price, easy breakage, and difficulty in increasing the diameter. Therefore, semiconductor optoelectronic devices using conventional compound semiconductor substrates do not have sufficiently satisfactory characteristics for practical use.

For those using a silicon single crystal substrate, there is a difference of 4 or more in the number of lattice paths between the silicon single crystal and the gallium arsenide single crystal, resulting in lattice mismatch between these crystals. As a result, lattice distortion and lattice defects occur in gallium arsenide single crystals, making it difficult to obtain good characteristics for electronic and optical devices made of gallium arsenide single crystals, resulting in problems such as a lack of reliability and reproducibility. Ta.

The present invention is intended to solve these problems, and its purpose is to integrate a light-emitting element, a light-receiving element, and an electronic element with excellent characteristics and high reliability on the same substrate, thereby making it practical. The purpose of the present invention is to provide a semiconductor optoelectronic device with high performance.

Means for Solving Problems] The semiconductor optoelectronic device of the present invention includes a silicon single crystal substrate, an amorphous insulating film existing on the whole or a part of the front or back surface of the silicon single crystal substrate, and the amorphous It consists of a compound semiconductor thin film existing on the whole or part of the surface of the insulating film and a multilayer compound semiconductor thin film existing on the whole or part of the surface of the compound semiconductor thin film, and the compound semiconductor thin film is a single crystal thin film formed by a grapho-epitaxial growth method. The multilayer compound semiconductor thin film is made of a multilayer single crystal thin film formed by an epitaxial growth method, and the silicon single crystal substrate, the compound semiconductor thin film, and the multilayer compound semiconductor thin film are used as constituent materials of a light emitting element or a light receiving element. , an electronic element for operating a light emitting element or a light receiving element made of a silicon semiconductor, and an electronic circuit having signal processing and arithmetic functions are formed on the outer surface or the back surface of the silicon single crystal substrate.

[Embodiment 1] FIG. 1 shows an embodiment of the present invention. In Figure 1, 1
It is an n-type silicon single crystal substrate with a (100) plane direction and an impurity concentration of about 1015 F1. A layer of Si 0 of several microns thick is formed on the surface of the n-type silicon substrate by thermal oxidation, chemical vapor deposition, or sputtering.
It is an amorphous insulating film made of 2 (silicon dioxide).

On the surface of this amorphous insulating film, rectangular stripe grooves with a depth of about 10 to 1'0000 angstroms and a width of 01 to 10 microns in culmability are formed by etching at a pitch of 0.1 to 10 microns. In the etching method, wet etching method using hydrogen fluoride-based etchant and Freon (
There is a reactive ion etching method using OF4) etc. as a reactive gas. The length ζ direction of the groove is arbitrary. In this example, SjO□ was used as the amorphous insulating film, but
Silicon nitride (SixNy), alumina (1s
120s) etc. can be used. 3 is an n-type gallium arsenide single crystal thin film grown graphoepitaxially on the amorphous insulating film. The graphite epitaxial growth of gallium arsenide single crystals is first carried out by vapor phase epitaxy, organometallic vapor phase epitaxy, molecular beam epitaxial method, etc.
An amorphous or polycrystalline gallium arsenide thin film is deposited on the surface of a grooved SiO2 film as shown in 2, and then heated using a laser, an infrared lamp, a heater, etc.
Single crystals can be grown by rearranging gallium arsenide along grooves. The thickness of a graphoepitaxially grown gallium arsenide single crystal is several to several tens of microns. In order to improve the single crystallinity on the surface of gallium arsenide, single crystal gallium arsenide with a good pattern is grown on the surface of the graphoepitaxial gallium arsenide crystal by a thermal equilibrium growth method such as liquid phase growth or vapor phase growth. You can let it grow. The graphoepitaxial method can be applied not only to gallium arsenide, but also to other group V compound semiconductors, U-Vl group compound semiconductors, group II compound semiconductors,
Can be used to grow silicon and other crystals. 1st
Are numbers 4 to 8 in the diagram, including number 3, double heterostructures? )-N junction semiconductor laser is a compound semiconductor thin film. 4 is the first crystal layer consisting of n-type aluminum gallium arsenide fast crystals, 5 is an active layer consisting of aluminum gallium arsenide fast crystals with a low impurity concentration, and 6 is a p-type aluminum gallium arsenide fast crystal. A second cladding layer made of crystal, 7 a lightning current restriction layer made of n-type gallium arsenide, and 8 a surface cap layer made of p-type gallium arsenide. In this embodiment, a double heterostructure semiconductor laser diode is manufactured, but it is also possible to manufacture a distributed feedback laser, a multiple quantum well laser, a superlattice laser, or the like. Reference numeral 16 denotes an electrode consisting of 8U-Zn/8U edges for making geometric contact with the p-type gallium-arsenide layer of 8.

9 is a p+ type layer formed by introducing impurities into the external silicon single crystal substrate, and 10 is an n+ type layer formed by introducing impurities into the aforementioned p type layer. 1.9 and 252. - -Comb 4 10fn7+wW bipolar transistor is formed.

That is, 1 is the collector, 9 is the base, and 10 is the emitter. Reference numeral 11 designates a surface inoculation film of the silicon substrate, and reference numeral 12 designates a surface protection film of the compound semiconductor layer. This is an At electrode that makes ohmic contact with silicon. Reference numeral 14 denotes an Au-G'g/A% electrode having ohmic contact from an n-type gallium arsenide single crystal thin film. 15 is wiring.

In the structure shown in FIG. 1, the n-side of the semiconductor laser diode is connected to the collector portion of the bipolar transistor. ζ
Furthermore, by setting the p-side of the semiconductor laser diode to a positive voltage potential and the emitter of the bipolar transistor to a negative potential, and applying a certain potential to the base of the bipolar transistor, a current flows through the semiconductor laser diode, causing laser oscillation. Semiconductor optoelectronic devices emit laser light. The intensity of the emitted laser light can be controlled by the base current of the bipolar transistor.

This embodiment is an example of a semiconductor optical single-device device 7'; , -1p10- , <'''), '', '1 in which a semiconductor laser and a driving bipolar transistor are integrated. A field effect transistor, a static induction transistor, etc. may be used instead of a bipolar transistor.

Alternatively, a plurality of semiconductor lasers and a plurality of transistors may be integrated.

[Embodiment 2] FIG. 2 shows a second embodiment of the present invention. The feature of this embodiment is that a semiconductor laser, a photodiode, and a driving transistor are integrated on the same substrate surface.

17 in FIG. 2 is a p-type silicon single crystal substrate.

1' is an n-type silicon single crystal film epitaxially grown on the p-type silicon single crystal substrate. The specifications and purpose of use of this n-type silicon single crystal film are as described in Example 1.
It is the same as a silicon single crystal substrate. 2' to 8 in Figure 2
' and 16' are 2 to 8 and 16 described in Example 1
corresponds to 18 is a P+ type diffusion layer for element isolation.

19, 21.23 are P+ type diffusion layers, 20.22 is? +,
It is a + type diffusion layer. 24 is a silicon surface passivation film, and 25 to 32 are metal poles that make ohmic contact with each region of the silicon. 1″ is the collector, 19 is the base, 20 is the emitter, 25,
26 and 27 are collector and pace emitter electrodes, respectively, forming a first bipolar transistor.

1"', 21, 22, 28.29 and 30 are the above 1
'', 19 degrees, 20 degrees, 25 points, 26 and 27, respectively, to form a second bipolar transistor. Side electrodes, A”, 23.31 and 3
2 forms a p+n+ photodiode. A first bipolar transistor drives a semiconductor laser, and a second bipolar transistor drives a semiconductor laser.
A bipolar transistor drives the photodiode. Since this semiconductor optoelectronic device receives and emits light in a single chip, it can be used not only as a repeater for signal transmission through optical fibers, but also in optical amplifiers, optical-to-optical signal converters, and the like.

Although a p+n+ photodiode is used as the photodiode in this embodiment, a pin photodiode or an avalanche photodiode can also be used.

[Embodiment 3] One embodiment of the present invention is shown in FIG. The feature of this embodiment is that a semiconductor optoelectronic device is constructed using both the front and back sides of a silicon substrate.

In FIG. 3, numeral 35 is a p-type silicon single crystal substrate which has been polished to a mirror finish on both the front and back surfaces. The surface direction of the board is (
100) and the impurity concentration is about 1×1011'crrL-3. 64-40 and 41 are 2 shown in Example 1
8 and 16, a laser element is formed on the back side of a silicon single crystal substrate. 35 is a compound semiconductor thin film grown by a grapho-epitaxial method, and 36 to 40 are compound semiconductor thin films grown by a general epitaxial method. 41 and 42 are metal electrodes.

MOS FET OKetal-oxide-8 formed on the back side of the p-type silicon single crystal substrate of 43 x 33
emiconthbctor Fieldl Bffe
The n+ type source region of the ct transistor is the drain region. This n+ type region is formed by ion implantation or diffusion. 44 is a gate insulating film, 45 is a gate electrode, 46 is an insulating film for surface buffing, and 47 is a metal wiring. The MOSFET formed on the front side constitutes an electronic circuit having signal processing and calculation functions. A heavy element for driving the light-receiving/emitting element formed on the back side may be formed on the front or back side of the silicon substrate.

The light receiving element may also be formed in the same manner. These multiple elements are organically coupled and controlled by an electronic circuit with arithmetic functions, so they can be used as an interface for repeaters and terminals in optical signal transmission systems using optical fibers.

〔Effect of the invention〕

The present invention has the following effects.

(2) A plurality of light emitting elements, light receiving elements, driving electronic elements, and signal processing arithmetic elements can be integrated on the same substrate. Further, by integrating the device, it becomes easier to downsize the device, and a highly reliable semiconductor optoelectronic device can be obtained.

(2) Since the compound semiconductor thin film is formed on the silicon substrate with an inert insulating film such as 5IC12 as an intermediate layer, impurity contamination into the silicon single crystal substrate can be avoided when forming the compound semiconductor thin film. Further, there is little mutual interference between the element made of the compound semiconductor thin film and the electronic element on the surface of the silicon substrate, and the electrical controllability of the device is good. Also, the device is easy to design.

■ The introduction of grapho-epitaxial technology eliminates the problems of crystal distortion and crystal defects caused by lattice mismatch in the grown single crystal, making it possible to obtain devices with good characteristics. Furthermore, since many types of compound semiconductor single crystals can be grown, many types of semiconductor optoelectronic devices can be constructed.

■ Existing silicon brainer technology can be applied to silicon electronic devices and silicon photodiodes that are formed on the surface of silicon single crystal substrates, making it possible to create devices with excellent performance, reliability, and functionality.

■ Silicon single-crystal substrates are being mass-produced and large-area substrates can be obtained at low cost. Furthermore, the quality of the silicon single crystal substrate is also good. Therefore, semiconductor optoelectronic devices using silicon single crystal substrates can be mass-produced with high yield and are therefore inexpensive.

[Brief explanation of drawings]

Figures 1 to 3 outline specific embodiments of the present invention. Figure 1 shows an example in which a semiconductor laser element and a driving silicon electronic element are integrated on the same silicon substrate, and Figure 2 shows an example in which a semiconductor laser element, a silicon photodetector, and a driving silicon electronic element are integrated on the same silicon substrate. FIG. 3 is a diagram showing an embodiment, and FIG. 3 is a diagram showing a semiconductor laser on the surface of a silicon substrate, and an embodiment in which a driving element and a Shingan processing arithmetic element are integrated on the surface. 1... N-type silicon single crystal substrate 1', 1", 1"'... N-type silicon single crystal 2, 2',
34...Amorphous insulating film 3, 3.35...Gallium arsenide single crystal thin film 4.4', 3
6...N-type aluminum/gallium arsenic early crystal 5.5', 37...aluminum/potassium/arsenic early crystal 6,6', 38...p-type aluminum/gallium/arsenic early crystal 7,7', 39 ...N-type gallium arsenide 8.8', 4
0...p-type gallium arsenide 9...silicon layer 10...silico/n-type layer 11...surface hashipation film 12...surface protection film 13...electrode 14...electrode 15...wiring 16.16' , 41... Electrode 17... P type silicon single crystal substrate 18... P 10 type diffusion layer 19.21.23... P 10 type diffusion layer 20.22... N 10 type diffusion layer 24... Surface passivation film 25-32...Metal electrode 33...P-type silicon single crystal substrate 42...Electrode 43...nx-type source φ drain region 44...Gate insulating film 17=45...Gate electrode 46...Surface passivation Insulating film 47 for metal wiring or more

Claims (4)

[Claims] (1) a silicon single crystal substrate; an amorphous insulating film existing on the entire or part of the front or back surface of the silicon single crystal substrate;
A semiconductor optoelectronic device comprising a compound semiconductor thin film existing on the whole or a part of the surface of the amorphous insulating film and a multilayer compound semiconductor thin film existing on the whole or a part of the surface of the compound semiconductor thin film. (2) The compound semiconductor thin film is a single crystal thin film formed on the surface of the amorphous insulating film by a graphoepitaxial growth method, and the multilayer compound semiconductor is a multilayer single crystal thin film formed on the surface of the compound semiconductor thin film by an epitaxial growth method. A semiconductor optoelectronic device according to claim 1, characterized in that the semiconductor optoelectronic device comprises: (3) At least one of the silicon single crystal substrate, the compound semiconductor thin film, and the multilayer compound semiconductor thin film is a constituent material of a light emitting element having an electron/light conversion function or a light receiving element having a light/electron conversion function. A semiconductor optoelectronic device according to claim 1, which is used as a semiconductor optoelectronic device. (4) On the front or back surface of the silicon single crystal substrate, at least one of an electronic element that operates the light emitting element or the light receiving element made of a silicon semiconductor, and a plurality of electronic elements having signal processing and calculation functions. A semiconductor optoelectronic device according to claim 1 or 3, characterized in that the semiconductor optoelectronic device is formed with: