Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
59 words
In a process for etching a substrate with the aid of a gas plasma produced either by ultra-high frequency waves, or by radio-frequency waves and ultra-high frequency waves, the improvement comprising that the gaseous medium used for forming the plasma comprises at least one non-carbon-containing fluorinating gas, at least one rare gas and at least one non-carbon-containing oxidizing gas.
Claim 2
Dependent Claim
59 words
In a process for etching a substrate with the aid of a gas plasma produced either by ultra-high frequency waves, or by radio-frequency waves and ultra-high frequency waves, the improvement comprising that the gaseous medium used for forming the plasma comprises at least one non-carbon-containing fluorinating gas, at least one rare gas and at least one non-carbon-containing oxidizing gas.
Claim 3
Dependent Claim
25 words
Process according to claim 1, characterized in that the gaseous medium also comprises at least one other gas chosen from among nitrogen and chlorine-containing gases.
Claim 4
Dependent Claim
24 words
Process according to any one of the claims 1 and 2, characterized in that the non-carbon-containing fluorinating gas is sulphur hexafluoride SF 6 .
Claim 5
Dependent Claim
26 words
Process according to any one of the claims 1 and 2, characterized in that the rare gas is argon or a mixture of argon and helium.
Claim 6
Dependent Claim
19 words
Process according to any one of the claims 1 and 2, characterized in that the oxidizing gas is oxygen.
Claim 7
Dependent Claim
19 words
Process according to claim 1, characterized in that the gaseous medium is constituted by sulphur hexafluoride, argon and oxygen.
Claim 8
Dependent Claim
48 words
Process according to claim 6, characterized in that the respective flow rates of sulphur hexafluoride, argon and oxygen are 4 to 500 cm 3 standard/min for SF 6 , 4 to 500 cm 3 standard/min for Ar and 2 to 500 cm 3 standard/min for 0 2 .
Claim 9
Dependent Claim
20 words
Process according to claim 1, characterized in that the gaseous medium is constituted by sulphur hexafluoride, argon, oxygen and nitrogen.
Claim 10
Dependent Claim
58 words
Process according to claim 8, characterized in that the respective flow rates of sulphur hexafluoride, argon, oxygen and nitrogen are 4 to 500 cm 3 standard/min for SF 6 , 4 to 500 cm 3 standard/min for Ar, 1 to 300 cm 3 standard/min for O 2 and 1 to 300 cm 3 standard/min for N 2 .
Claim 11
Dependent Claim
22 words
Process according to any one of the claims 1, 2 and 6 to 9, characterized in that the substrate is of silicon.
Claim 12
Dependent Claim
27 words
Process according to any one of the claims, 2 and 6 to 9, characterized in that etching is performed under a pressure of 0.1 to 300 Pa.
Claim 13
Dependent Claim
113 words
Process according to any one of the claims 1, 2 and 6 to 9, characterized in that etching is carried out by means of a gas plasma produced by ultra-high frequency waves and radio-frequency waves by confining on the substrate by a cell made from a material transparent to ultra-high frequency waves a gas plasma produced by transverse monomode coupling between a waveguide traversed by ultra-high frequency waves and the cell in which at least part of the gaseous etching medium circulates perpendicular to the ultra-high frequency waves to be directed onto the substrate and by simultaneously applying to the substrate a d.c. or a.c. voltage having a frequency in the radio-frequency range.
Claim 14
Dependent Claim
91 words
Process according to any one of the claims 1, 2 and 6 to 9, characterized in that etching is carried out by means of a gas plasma produced by ultra-high frequency waves by confining on the substrate using a cell made from a material transparent to ultra-high frequency waves a gas plasma produced by transverse monomode coupling between a waveguide traversed by ultra-high frequency waves and the cell in which at least part of the gaseous etching medium circulates perpendicular to the ultra-high frequency waves to be directed onto the substrate.