JPS6279658A - Manufacture of resistance element in semiconductor device - Google Patents

Abstract

PURPOSE:To set resistance values accurately and easily by a method wherein an insulating layer is formed in an activation layer by ion implantation by the converging beam method. CONSTITUTION:Si ions are implanted into a GaAs substrate 1 and then annealing is accomplished for the formation of an activation layer 2 and then an ohmic electrode 3 is built to be in contact with the activation layer 2. The resistance is measured and a region 7 to be insulated is defined on the basis of the difference from the desired resistance value. The ion implantation region 7 is then exposed to a converging Be ion beam accelerated for example at 200keV. The portion subjected to the Be ion implantation serves as a insulating region 7. Use of an electrically steerable converging ion beam ensures accurate ion implantation, which ensures a high-precision resistance value.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for forming a resistance element on a surface portion of a semiconductor substrate in manufacturing a semiconductor device.

[Conventional technology]

FIG. 2A-0 is a plan view showing the main stages of a conventional manufacturing method for such a resistance element. First, ions are implanted into a part of the surface of a semiconductor substrate (1).

and annealing to form an active layer (2), and ohmic electrodes (3) in ohmic contact are formed at both ends of the active layer (2) (FIG. 1A). Next, measure the resistance value, calculate and determine the position and size of the etched region where a part of the active layer 12) should be etched to obtain the desired resistance value, and After forming a resist film (C4) on the entire upper surface of the semiconductor substrate (1) including the top of (3), an opening (5) corresponding to the etching region is formed (FIG. 2B). After that, the semiconductor (4) is removed using the resist film (4) having the opening (fi) as a mask (
Figure 2 O). In this way, by narrowing the width of the central portion of the active layer (2) and increasing the resistance value, the overall resistance value can be controlled and a desired resistance element can be obtained.

[Problem that the invention seeks to solve]

In the conventional method, it is difficult to match the position of the pattern of the opening (5) in the resist film (4) with an accuracy of ±1 μm or less, and it is difficult to accurately control the resistance value. Also, the position of the opening (5) in the resist film (4) for resistors with different etching nozzle (6) shapes.

It is necessary to change the size of each, as shown in Figure 2B.

There was a problem that the process shown in No. 0 had to be repeated for resistors with different pattern shapes, resulting in a long process.

This invention has been made to eliminate the above-mentioned problems, and an object thereof is to provide a method for dipping a resistor element in a semiconductor device, which can accurately and easily control the resistance value.

[Means for solving problems]

In the method for manufacturing a resistance element according to the present invention, ions are implanted into the active layer using a focused ion beam to form an insulating layer.

[Effect]

In the method for manufacturing a resistive element in a semiconductor device according to the present invention, a region implanted with a focused ion beam is made into an insulating layer, thereby making it possible to control the resistance value.

〔Example〕

FIGS. 1A and 1B are plan views showing the main stages of an embodiment of the present invention. First, ions 81 are implanted and annealed onto a GaA3 substrate (1), and an active layer (21fi) is implanted and annealed.
? AumGe1 is deposited in contact with the active layer (2), patterned by a lift-off method, and then heat treated to completely form the ohmic electrode (3).
Figure 1A). This resistance value is measured, and the entire region (7) to be formed into an insulating layer is determined based on the difference from the desired resistance value. Then, the ion implantation region (7) is irradiated with a Be focused ion beam accelerated to, for example, 200 keV. The ion-implanted portion at this time becomes an insulating region (7). (fJI, Figure 1B
) Although a GaAa substrate was used in the above embodiment, it may also be made of Sl or other Taka-Ma group or N-W group semiconductors. Furthermore, Be of 200 meV − is used as a focused ion beam.
Although t- is used, any other material that can form the insulating layer N may be used.

〔Effect of the invention〕

As described above, since an electrically deflectable focused ion beam is used, the ion implantation region can be formed accurately and the resistance value can be determined with high precision. Since an arbitrary pattern can be drawn using an ion beam, it can easily be applied to resistors having active layers with different patterns.Furthermore, since no resist is used, the process can be shortened.

[Brief explanation of drawings]

Figure 1 is a plan view illustrating an embodiment of the present invention, and Figure 2 is a plan view illustrating a conventional process. In the figure, (1) is a semiconductor substrate, (2) is an active layer, (
3) ohmic electrode, (7) is an insulating region. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] (1) A process of forming an active layer that constitutes a resistance element on the surface of a semiconductor substrate, forming ohmic electrodes that make ohmic contact at both ends of the active layer, and injecting necessary ions into a part of the active layer. 1. A method for manufacturing a resistive element in a semiconductor device, comprising the step of implanting a resistive element using a focused ion beam and using the ion implanted portion as an insulating region to obtain a resistive element having a desired resistance value.