JPS62141720A - Semiconductor-insulator films lamination structure - Google Patents

Abstract

PURPOSE:To obtain lamination of III-V compound semiconductors without thermal damage and thermal strain, by using a nitriding aluminum crystal, or a mixed crystal of nitriding aluminum and nitriding gallium as an insulator film on a semiconductor. CONSTITUTION:A nitriding aluminum crystal, or a mixed crystal of nitriding aluminum and nitriding gallium is used as an insulator film in lamination structure in which semiconductors are laminated on the semiconductor through the insulator film. Nitriding aluminum and nitriding gallium have thermal expansion factor of about 5X10<-6>K<-1>, which is not much different from that of semiconductor, capable of reducing thermal strain. Because a combination of nitrogen and a III group element becomes effective for stabilizing a surface of a III-V compound semiconductor, the said material group is useful for a decrease in a damage on the surface of the III-V compound semiconductor.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a laminated structure of semiconductor and insulator films.

(Conventional technology) Conventionally, 5OI (semiconductor on-in-insulator) using a semiconductor/insulator film laminated structure and beam annealing technology has been developed.
Ta: Sem1conductor on In5ul
ator) structure has been created for silicon. At this time, if the insulator film is a single crystal, the SOI structure is
This makes it easy to create. In the case of silicon, magnesia spinel (Mg0-AII, O,) or calcium fluoride (CaF, ) is epitaxially grown on a substrate, and single crystal silicon is grown on it.

(Problems to be Solved by the Invention) However, the epitaxial growth temperature of magnesia spinel is approximately 900° C. or higher, and at this temperature, the surface of the -V compound semiconductor is thermally damaged. The coefficient of thermal expansion of fluoride is approximately 20X 10"K"', which is 3xlQ-' of silicon.
x-', gallium arsenide's 6 ,
It is an object of the present invention to provide a semiconductor/insulator film laminated structure that can also use an IV compound semiconductor.

(Means for solving the problem) In the present invention, aluminum nitride crystal,
Alternatively, a mixed crystal of aluminum nitride and gallium nitride may be used as the insulating film. The growth method is appropriately selected depending on the substrate semiconductor. For example, when growing aluminum nitride on a silicon substrate, low pressure MOC 2 may be performed at a temperature of about 900° C. using trimethylaluminum and ammonia as raw materials. In addition, when growing aluminum nitride on an IV compound semiconductor, it can be grown using ECR (electron cyclotron resonance) plasma using trimethylaluminum and ammonia as raw materials, or it can be grown using trimethylaluminum and hydrazine as raw materials.
MOCVD may be performed at a temperature of 001:: or higher.

When using a mixed crystal of aluminum nitride and gallium nitride,
Approximately 40 g of aluminum nitride is contained in the mixed crystal. If the amount of aluminum nitride is less than this, the insulating properties of the mixed crystal will not be sufficient.

(Function) The thermal expansion coefficient of aluminum nitride and gallium nitride is approximately 5X.
10-'K'' has a smaller difference in thermal expansion coefficient from that of semiconductors than conventional materials, making it possible to reduce thermal strain.

Furthermore, since the bond between nitrogen and Group I elements has an effect on stabilizing the surface of a 1-V compound semiconductor, it is expected that the above material system will be useful in reducing damage to the surface of a 1-V compound semiconductor.

(Example) In this example, an insulating film was formed on a gallium arsenide (GaA+s) substrate, which is one of the IV compound semiconductors, and then the same GaAs as the substrate was grown thereon.

Chemically etch a GaAs (111) wafer.

Trimethyl gallium (TMG) and arsine (AsHa)
Approximately 1,000 sheets are deposited on a wafer using the MOCVD method using
Grow AGaAs. Using this as a substrate, trimethylaluminum (TMA), hydrazine (N, H,
) as a raw material, perform AJN 0M0CVD. At this time, the T MA and N*H4 temperatures were 20°C, and the bubble hydrogen flow rate was 5α/min, 200=6. The substrate temperature is 600
℃, the total flow rate was set to 8 m/min, and the pressure was set to 80 Torr.
An AIN film with a thickness of about 50 OA was obtained in 0 minutes. Furthermore, GaAs could be grown by MOCVD using TMG and AsH as raw materials.

TMG is used to create mixed crystals of aluminum nitride and gallium nitride.
, TMA, N, H, were used as raw materials. TMG, TM
A.

N and H4 temperatures are -12℃, 20℃, and 20t, respectively.
, bubble hydrogen flow rate is II:e, 4C per minute, respectively.
a, 200ctI.

The substrate temperature is 600℃, the total flow rate is 8g/min, and the pressure is 8℃.
orr for about 500X for 10 minutes. .

G A44 N... was created.

(Effects of the Invention) According to the present invention, a stacked structure of semiconductor/insulator films that avoids thermal damage and thermal distortion is realized, and it becomes possible to stack [-V compound semiconductors as well.

Claims (1)

[Claims] In a stacked structure in which an insulating film is layered on a semiconductor, and a semiconductor is further layered on top of that, aluminum nitride crystal, aluminum nitride crystal, etc. are used as the insulating film.
Alternatively, a semiconductor/insulator film laminated structure characterized by using aluminum nitride/gallium nitride mixed crystal.