JPS62113425A - Semiconductor manufacturing equipment - Google Patents

Abstract

PURPOSE:To accurately determine the end of an etching process by a method wherein a heating means is provided on the wall of a reaction container. CONSTITUTION:A heating wire 7 is provided on the outer wall of a chamber 1 opposite to a termination detecting sensor 5 so that the emission spectrum of plasma generated in the chamber 1 may reach the termination detecting sensor 5 without being shielded by the heating wire 7. The inside wall of the chamber 1 is warmed when an electric current is applied to the heating wire 7 attached to the chamber 1, which prevents etching-created products from adhering to the inner wall of the chamber 1. This ensures accurate detection of the end of etching.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to semiconductor manufacturing equipment, and particularly relates to end point determination of dry etching equipment. This figure shows the configuration of the semiconductor manufacturing equipment used for etching, in which (11 is a completely transparent channel into which an appropriate etching gas is fed, <-2 (21
1''j Inside the upper electrode, (31 is the semiconductor substrate to be etched, (4) is the semiconductor substrate (31 is placed on the lower 1! pole, (5) is a sensor that detects the etching gas by the emission spectrum, This sensor (51 is provided on the outer periphery of the channel/<-m. (6) is the sensor (51)
This is the stand on which 61 is attached.

Next, W will be explained. Introduce an appropriate gas into the chamber (1) and use the pump to defecate (1).
) is reduced to, for example, about 0.1 to 10 (Torr), and in this state, when harmonic power is applied to the upper electric fit (21), a glow discharge is generated in the chamber +Il, and this discharge generates plasma. The chemically active component and lower part of the plasma that exist in the low-temperature plasma are generated.
Etching is performed by a chemical reaction with the layer to be processed on the surface of the semiconductor substrate (3) placed on 41. In order to perform etching with high precision, there must be no material to be etched.
It is necessary to detect when the base material has come out. When a substance is excited in a plasma state and emits light, it has a wavelength that corresponds to its energy. For example, the characteristic wavelength of SiF'4 produced when etching a nitride film is 336 (nm), and by examining this with the end point detection sensor (5), the presence or absence of the substance and changes in the amount can be detected. The end point of etching can be detected.

[Problem that the invention seeks to solve]

In conventional semiconductor manufacturing equipment, the number of times of etching is repeated (reaction products generated during etching adhere to the inner wall surface of the chamber (1), and the surface becomes cloudy, making it difficult to judge the end point by the sensor (6)). The reason for this problem is that while normal reaction products are exhausted in a gaseous state, when a reaction product with a low vapor pressure, such as AtCl3, is produced, the chamber ( !; It solidifies and becomes particles and adheres to the inner wall, which has a lower temperature than the inside.

The present invention was made to solve the above-mentioned problems, and an object of the present invention is to provide a semiconductor manufacturing apparatus that can reliably determine the end point of etching.

[Means for solving problems]

The semiconductor manufacturing apparatus according to the present invention is capable of reliably determining the end point by providing a heating means on the wall surface of the reaction tank.

[Effect]

By heating the wall surface of the reaction tank using the semiconductor manufacturing apparatus (d) of the present invention, the reaction product adhering to the inner wall of the reaction tank can be eliminated and the end point of etching can be reliably determined.

〔Example〕

FIG. 1 is a perspective view showing an example of the present invention.

Moreover, FIG. 2 is a partially enlarged view. (11 to (6) are completely the same as the conventional device shown in Fig. 3, and their explanations are omitted. It must be arranged so that the emission spectrum of the plasma generated in the chamber (1) reaches the end point detection sensor (51) without being blocked by the heat ray (7).

In the main conductor manufacturing apparatus configured as described above, the inner wall of the chamber (ll) is heated by passing a current through the secondary heating wire (7) housed in the chamber (fl+), and reaction products generated during etching are heated. can prevent adhesion.

In addition, in the above embodiment, there is a hot wire (7) on the outer wall of the chamber mountain.
Although a hot wire (7) may be provided on the inner wall of the chamber (11). In this case, the effect of preventing reaction product adhesion will be improved, but the hot wire (7) may be damaged and the chamber H
cause internal contamination. Therefore, when using this method, it is necessary to coat with quartz or the like.

Alternatively, a hot wire (7) may be embedded inside the chamber (1), producing the same effect.

〔Effect of the invention〕

As explained above, the present invention has a partial structure in which a heating means is provided on the wall of the reaction tank, so that the end point can be determined reliably and dry etching can be performed with high accuracy.

[Brief explanation of drawings]

! FIG. 1 is a perspective view showing a semiconductor manufacturing apparatus according to an embodiment of the present invention. Figure IJ2 is a partially enlarged view, and Figure 3 is a perspective view showing a conventional semiconductor manufacturing apparatus. In the figure, fil is a chamber, (21 is an upper electrode,
(31 is a semiconductor substrate, (4) is a lower electrode, (51 is a sensor for detecting the end point, (6) is a sensor mounting base, and (7) is a hot wire. The same symbols in each figure are the same or equivalent. shall indicate the part.

Claims (2)

[Claims] (1) a reaction tank that houses a semiconductor substrate to be dry etched; a pair of electrodes that are provided in the reaction tank to face each other and apply high frequency power to the etching gas introduced into the reaction tank; Etching completion detection means is provided on the outer periphery of the reaction tank and detects the emission spectrum of plasma generated by the high-frequency power; A semiconductor manufacturing apparatus comprising a reaction product adhesion prevention means for preventing generated reaction products from adhering to an inner wall surface. (2) The semiconductor manufacturing apparatus according to claim 1, wherein the reaction product adhesion prevention means is a hot wire using a heating resistor.