JPS63249329A - Plasma cvd system - Google Patents

Abstract

PURPOSE:To improve a step coverage due to the step gap on wafers by moving the wafers with the diffusion of reactive active species. CONSTITUTION:A reaction chamber (reactive active species forming chamber) 1 is kept in a vacuum, a gas flows from a reactive gas inlet 3, a glow discharge is generated between coaxial type electrodes 8 applied with alternating current voltage (high-frequency generator) 5, the reactive gas is excited and active species are formed. The active species are diffused toward the substrate (wafers) 6 on a stage 7 wherein a temperature is controlled and a film is formed on the substrate. Since the stage 7 moves along an arc in the direction shown by an arrow while being rotated, the angle of the substrate with respect to the active species is changed, overhanging is restrained and the film is formed even on a step region. This improves a step coverage.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a plasma CVD apparatus, and more particularly, to a plasma CVD apparatus with better step coverage.

[Conventional technology]

Conventional plasma CVD equipment applies alternating current voltage between opposing electrodes, excites the gas between the electrodes with that energy, and generates active species, thereby forming a film on a substrate fixed on one electrode. I was doing membranes.

[Problem that the invention seeks to solve]

Conventionally, in plasma CVD, the step coverage of patterns on wafers has been affected compared to normal pressure CVD and low pressure CVD.
It was said that C. However, as the pattern on a wafer becomes finer, the vertical bjLIII cannot follow it, so the aspect ratio of the pattern tends to improve. For this reason, even in plasma CVD, overhang becomes a problem and there is a drawback that the step coverage becomes insufficient.

[Means for solving problems]

The present invention eliminates the above-mentioned conventional drawbacks and provides a plasma CVD apparatus with better step coverage. The basic configuration of the present invention will be described below.

First, a reactive gas is caused to flow between electrodes to which an alternating voltage is applied to generate reactive species. Next, the substrate is placed downstream of the reactant gas at an appropriate distance from this electrode. Furthermore, the method further includes the step of moving the substrate in the reactive species diffused from the glow discharge region.

〔Example〕

Next, Example 1 of the present invention will be described with reference to FIG. 1. The reaction chamber (1) is maintained at a vacuum level of several mTorr to several Torr. Gas flows through the reactant gas inlet (2) and glow discharge occurs between the coaxial electrodes (4) to which an alternating current voltage (5) is applied, the reactant gas is excited and active species are formed.

The activated species were placed in a stage (7
) on the substrate (6) and forms a film on the substrate. Since the stage (7) moves on an arc while rotating in the direction of the arrow, the angle of the substrate with respect to the active species changes.
Overhangs are suppressed and the film is also deposited on the stepped portions, improving the performance of the stepped pulpit. Excess gas is exhausted from the outlet (3).

[Example 2] Next, Example (n) of the present invention will be described. In this example, the configuration of the reactive species generating section in Example 1 was changed from a coaxial type to a parallel plate type. Other basic configurations are the same as in the first embodiment.

〔Effect of the invention〕

As explained above, in the plasma CVD apparatus according to the present invention, since the wafer moves against the diffusion of reactive active species, step coverage caused by steps on the wafer can be improved. Furthermore, since the reactive active species generation section and the reaction chamber are separated, only reactive active species with relatively long lifetimes reach the reaction chamber, while charged particles with short lifetimes recombine and do not reach the reaction chamber. . Therefore, it has the effect of avoiding plasma damage.

[Brief explanation of drawings]

Figure 1 shows Example 1 of the present invention, and Figure 2 shows Example 1 of the present invention.
FIG. 1...Reactive species generation chamber, 2...
... Film formation chamber, 3... Reaction gas inlet,
4... Reaction gas outlet, 5... High frequency generator, 6... Wafer, 7... Stage, 8... Electric power very.

Claims (1)

[Claims] A plasma CVD apparatus characterized by a structure consisting of a chamber that generates active species of a reactive gas necessary for film formation by excitation with electromagnetic waves, and a separate film formation chamber connected to the active species generation chamber. .