JPH0344923A - Manufacture of semiconductor - Google Patents

Abstract

PURPOSE:To accelerate an etching speed and to improve uniformity of etching by providing an auxiliary electrode in addition to flat plate type electrodes provided in parallel, and employing a dry etching apparatus provided with a revolving magnetic field therearound. CONSTITUTION:In a dry etching apparatus, an auxiliary electrode 402 is provided in addition to flat plate type electrodes 401 placed in parallel, and a rotary magnet 403 is provided therearound. A wafer 405 is placed on one of the electrodes 401, SF6 gas is introduced into a reaction chamber 404, and a high frequency is applied to dry etch it. Then, a high etching speed is obtained. Further, the magnet 403 is provided to uniformly generate a magnetic field to make a plasma uniform, thereby improving the uniformity of etching.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to semiconductor manufacturing equipment, and particularly to dry etching equipment.

[Conventional technology]

A conventional dry etching apparatus is called a parallel plate reactive ion etching apparatus (hereinafter referred to as RIE).
The mainstream method was to apply high frequency waves to electrodes placed in parallel to generate plasma and perform etching. In this method, in order to increase the etching speed, it was necessary to increase the output of high frequency waves, which resulted in a problem of increased etching damage. Therefore, in order to obtain high-density plasma without increasing the output too much, devices that are equipped with an auxiliary electrode, generally called triode-type RIE, and devices that are combined with a magnetic field, generally called magnetron-type RIE, have appeared.

FIG. 1 shows a structure of a parallel plate type RIE, FIG. 2 shows an example of a structure of a triode type RIE, and FIG. 3 shows an example of a structure of a magnetron type RIE.

For example, when silicon nitride is etched using SF6 as the gas under the conditions considered to be optimal (Table 3 of Group 19, Table 21), the etching speed is sot'L, 2200
, 3350.3500 people/min.

Table 1 Table 2 [Problems and objectives to be solved by the invention] However, with the conventional technology, the etching speed is still not high enough, and when the degree of integration increases, the number of processes increases, and throughput becomes a problem However, there is a problem in that the device is not able to fully cope with this problem.

The present invention is intended to solve these problems, and its purpose is to increase the etching rate, increase the throughput, and further improve the uniformity.

[Means to solve the problem]

The semiconductor manufacturing apparatus of the present invention is a dry etching apparatus in which a wafer is placed on either of parallel flat plate electrodes and etching is performed by applying high frequency to the electrodes. and a rotating magnetic field around it.

〔Example〕

The present invention will now be described in detail based on examples.

FIG. 4 is an example of a schematic diagram of the semiconductor manufacturing apparatus of the present invention.
In addition to the parallel electrodes (401), there is an auxiliary electrode (402), which also has a rotating magnet (403). In addition, there are those that have auxiliary electrodes on the side, and those that use solenoid coils to obtain the magnetic field.

When silicon nitride is etched using the apparatus shown in FIG. 4 and SF6 as the gas under conditions considered to be optimal (Table 4), the characteristics shown in Table 5 are obtained.

Table 4 Table 5 As described above, if the apparatus of the present invention is used, an etching rate of about 1.5 times that of the conventional apparatus can be obtained. In this example, only the etching of silicon nitride using SF6 will be described. However, the present invention is not limited to this, and even if other gases are used to etch other materials, an etching rate higher than that of the conventional apparatus can be achieved.

The reason why the magnet was rotated in this apparatus was to generate a uniform magnetic field, make the plasma uniform, and improve the uniformity of etching.

〔Effect of the invention〕

As described above, if the semiconductor manufacturing apparatus of the present invention is used, it is more effective than the conventional apparatus. An etching speed about 5 times faster can be obtained, and the uniformity is improved.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the structure of a conventional parallel plate type RIE. FIG. 2 is a diagram showing the structure of a conventional triode type RIE. FIG. 3 is a diagram showing the structure of a conventional magnetron type RIE. FIG. 4 is a diagram showing the structure of the dry etching apparatus of the present invention. 101.201, 301, 401... Electrode 202.4
02...Auxiliary electrode 303.403...Magnet 104.204,304,404...Reaction chamber 105.
205, 305, 405... wafer 106, 206,
306,406...High frequency 107.207,307,
407...Gas inlet 108.208, 308, 40
8... Gas exhaust port and above, Seiko Epson Corporation

Claims (1)

[Claims] In dry etching equipment, a wafer is placed on either side of flat plate electrodes placed in parallel and etching is performed by applying high frequency to the electrodes. A semiconductor manufacturing device characterized by having a magnetic field.