Importance

Loading Importance Indicators...

Abstract

The present invention consists in a method of plasma treatment of a semiconductor substrate in a process chamber connected to a vacuum line via a valve, said treatment including a plurality of cycles comprising at least one etching step during which an etching gas is introduced alternating with at least one passivation step during which a passivation gas is introduction into said chamber, which method includes the following operations: (a) a reference pressure P.sub.ref is defined at which it is wished to effect the treatment, (b) the position of the valve is fixed during the first etching step, (c) the pressure in the process chamber is allowed to stabilize during n cycles, (d) the pressure in the process chamber is measured during the etching step during m cycles, with m at least equal to 2, and an average pressure value P.sub.c is calculated from the measurements effected, (e) after n+m cycles, the position of the valve is corrected with a view to obtaining a pressure in the process chamber that approximates the reference pressure value P.sub.ref, (f) the steps (c) to (e) are repeated until the calculated average pressure P.sub.c is substantially equal to the reference pressure value P.sub.ref so that it is no longer necessary to correct the position of the valve.

Loading the Abstract Image...

First Claim