JPH0618208B2 - Method for manufacturing semiconductor device - Google Patents

Description

The present invention relates to a method for manufacturing a semiconductor device, and more particularly to an ohmic semiconductor device formed on a first semiconductor substrate, a part of which is formed of a second semiconductor material. The present invention relates to a contact forming method.

[Conventional technology]

Conventionally, a semiconductor device, a part of which is formed on a first semiconductor substrate using a second semiconductor material, has a structure in which the second semiconductor is exposed on the surface during the device manufacturing process, and therefore, wiring etc. In the process, wiring materials and methods suitable for the first semiconductor and the second semiconductor are separately used.

[Problems to be solved by the invention]

In the above-mentioned conventional method, for example, the wiring process has to be performed separately for the first semiconductor and the second semiconductor, and the manufacturing process is complicated as compared with a semiconductor device made of silicon that requires only one wiring process. become. In addition, since the second semiconductor is exposed on the surface during the manufacturing process, impurity contamination by the second semiconductor becomes a problem, and the first semiconductor process line cannot be used after the second semiconductor is used. Further, when the second semiconductor material is less likely to make an ohmic contact than the first semiconductor material, the electrical characteristics of the device are unstable.

An object of the present invention is to provide a method of manufacturing a semiconductor device that solves the above problems.

[Means for solving problems]

According to the present invention, in manufacturing a semiconductor device having a second semiconductor on a part of a first semiconductor substrate, a step of forming a first semiconductor film on the n- or p-type second semiconductor, A step of ion-implanting an impurity having the same conductivity type as that of the second semiconductor into an interface between the film and the second semiconductor, and a step of simultaneously forming an electrode in a portion formed by the first and second semiconductors. A method of manufacturing a semiconductor device, comprising:

[Action]

By having the same first semiconductor film as the substrate on the second semiconductor, the second semiconductor is not exposed on the surface, there is no impurity contamination by the second semiconductor, and the process line of the first semiconductor can be used. It is not necessary to perform the wiring of (1) separately from the wiring of the first semiconductor. The process can be simplified by batch wiring. In addition, the native oxide film on the interface is mixed by ion-implanting impurities that become conductive type with the first semiconductor into the interface between the second semiconductor and the first semiconductor. The electron barrier can be removed. Moreover, since the second semiconductor side of the interface contains high-concentration impurities, ohmic contact is easily made and contact resistance can be reduced.

〔Example〕

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

FIGS. 1 (a) to 1 (c) show an embodiment of a silicon heterobipolar for explaining the manufacturing method of the present invention.

In FIG. 1 (a), phosphorus and boron are implanted into a p-type silicon substrate 1 having a specific resistance of 10 Ωcm by ion implantation at 1 × 10 ¹² / cm ² , 150 KeV and 1 × 10 ¹⁴ / cm ² , 30 KeV, respectively. After this is annealed to form an n-type collector 2 and a p-type base 3, an oxide film 4 is deposited to open the window of the emitter, and n-type silicon carbide which is an emitter material with a wide energy gap is formed. Is vapor-deposited by a CVD method using silane, propane, phosphine and hydrogen as a carrier gas to form an n-type emitter 6. Then the first
As shown in Figure (b), the silicon film 7 made of polysilicon is
Å Deposit 1x10 ¹⁴ / cm ² of phosphorus at the interface so that electrons can tunnel the electron barrier between silicon carbide and polysilicon, and perform rapid thermal annealing at 900 ° C for 5 seconds in nitrogen. . After that, Fig. 1
As shown in (c), base, collector, and emitter contact holes are formed, and wiring 8 is performed at the same time.

When the emitter material is epitaxially grown, the silicon film may be epitaxially grown after the emitter film is formed and the impurities may be ion-implanted as described above.

〔The invention's effect〕

As described above, according to the present invention, since the process of the first semiconductor can be used in the manufacture of the semiconductor device formed by using the second semiconductor material on a part of the first semiconductor substrate, the process can be simplified. An excellent effect can be obtained.

[Brief description of drawings]

1 (a) to 1 (c) are cross-sectional views showing a method of manufacturing an embodiment of the present invention in the order of steps. 1 ... Silicon substrate, 2 ... N-type collector 3 ... P-type base, 4,5 ... Oxide film 6 ... N-type emitter, 7 ... Silicon film 8 ... Wiring

Claims (1)

[Claims] 1. When manufacturing a semiconductor device having a second semiconductor on a part of a first semiconductor substrate, a step of forming a first semiconductor film on the second semiconductor of n-type or p-type; A step of ion-implanting an impurity having the same conductivity type as the second semiconductor into an interface between the one semiconductor film and the second semiconductor;
And a step of simultaneously forming an electrode on a portion formed of the first and second semiconductors.