JPH02201922A - Manufacture of semiconductor device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention changes the depth of a transistor pure region created in a semiconductor substrate using FIB to form transistors with different properties in local regions. It relates to technology for evaluating the characteristics of

[Conventional technology]

FIGS. 2(IL) to 2(6) are cross-sectional side views showing step by step a conventional method for manufacturing a semiconductor device. In the figure (1
] is a semiconductor substrate crystal, (2) is a transistor isolation region,
(3) is a transistor gate electrode, (4) is a resist,
mouth.

The eel uses impurity ion implantation to form a transistor, and the ell and field use ion implantation l511. An impurity implantation region formed by @ is shown. Note that ion implantation υ and ion implantation @z1, between impurity regions, and impurity region (material) indicate ion implantation with different energies and impurity regions with different depths, respectively.

Next, the manufacturing method will be explained. When trying to form different lower transistors on one semiconductor substrate, first, a transistor isolation region (2) is formed on the semiconductor substrate crystal (1) using an oxide film, etc., and a transistor gate electrode (3) is formed on the other active region. ) will be established. For example, when forming two different transistors, as shown in FIG. An impurity implantation region is formed at the end of the transistor gate electrode (3) that is not covered.Next, the resist (4) in the region covered with the resist (4) is removed as shown in FIG. One transistor region is covered with a resist (4), and ion implantations with different energies are performed as shown in Figure 2(b).By manipulating these resists (4), the area shown in Figure 2(6) is formed. As shown, transistors with different ion implantation depths can be fabricated in one wafer. Note that if more different transistors are desired to be formed, the above process will be repeated.

[Problem to be solved by the invention]

Since the conventional method for manufacturing a semiconductor device is performed as described above, the manufacturing process becomes complicated and the problem increases.

This invention was made to solve the above-mentioned problems, and it is possible to reduce the number of manufacturing process steps and form different transistors on one substrate relatively easily.

[Means to solve the problem]

The method for manufacturing a semiconductor device according to the present invention utilizes the local processability of FIB, and can easily change transistor characteristics. The transistor active region is locally made pre-amorphous by using the method, and then ions are implanted into the entire area.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
Figures (83-(+11) are cross-sectional side views showing the manufacturing method of a semiconductor device step by step. In the figure, (1)-(+11)
1.1511.1E and @ are the same as those shown in the conventional example of FIG. 2, so their explanation will be omitted. Round and double are FIBs with different energies (However, the ion species used are the same as the substrate crystal. Usually Si). @Turtle (branch) is a preamorphous region made amorphous by the FIB with different energy.

Next, the operation will be explained. First, the semiconductor substrate crystal (13
After forming a transistor isolation region (2) and a transistor gate electrode (31) on the top in the same manner as in the conventional method, the first
As shown in Figure (a), there is an FI in one transistor area.
A gap between preamorphous regions is provided using BrllJ.

Next, as shown in FIG. 1(b), a pre-amorphous region (material) is provided in the other transistor region with a FIB of different energy. Finally, as shown in FIG. 1(C), ion implantation is performed on the entire surface of the transistor region.
Since the transistor region is pre-amorphized as described above, even if ion implantation with the same energy is performed over the entire surface of the transistor region, transistors with different implantation depths can be obtained.

In the above example, the pre-amorphous region SU,@ is provided by FIBVlJ, Inc. using the same type of ion species as the semiconductor substrate crystal tl), and then the normal whole surface ion implantation Z]J is performed. Although described above, it is also possible to directly form a transistor using FIB ion implantation with different energies.

Further, although two different types of transistors are formed in the above embodiment, the same effect can be achieved even when three or more transistors are formed.

〔Effect of the invention〕

As described above, this invention simplifies the manufacturing process and allows local control of transistor characteristics, making it unnecessary to conduct experiments by changing ion implantation conditions between wafers as in the past. There are effects such as

[Brief explanation of the drawing]

1A to 1E are cross-sectional side views showing a method for manufacturing a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional side view showing a conventional method for manufacturing a semiconductor device. In the figure, (1) is a semiconductor substrate crystal, (2) is a transistor isolation region, (3) is a transistor gate electrode, group is an ion implantation region, et+, IX5 is an impurity implantation region, and (2).弼 is FIBlfllll, [ is a preamorphous region. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] 1. A method for manufacturing a semiconductor device, comprising making a desired region preamorphous using an FIB (Focused Ion Beam), and then performing ion implantation.