US 7,381,644 B1 · Pulsed PECVD method for modulating hydrogen content in hard mask

Abstract

A method for forming a PECVD deposited ashable hardmask (AHM) with less than 30% H content at a process temperature below 500° C., e.g., about 400° C. produces low H content hard masks having the property of high selectivity of the hard mask film to the underlying layers for successful integration of the film, and are suitable for use with 193 nm generation and below lithography schemes wherein high selectivity of the hard mask to the underlying layers is required. The low temperature, low H films are produced by use of a pulsed film hydrocarbon precursor plasma treatment that reduces the amount of hydrogen incorporated in the film and therefore drives down the etch rate of the hard mask thus increasing the selectivity. The lower temperature process also allows reduction of the overall thermal budget for a wafer.

Claims31

Dependent claims

A method of forming an ashable hard mask, comprising:

providing a semiconductor device substrate in a deposition chamber;
depositing on the substrate an ashable hard mask film by a plasma enhanced chemical vapor deposition (PECVD) process wherein the process temperature is below 500° C. and the resulting hard mask has a hydrogen content of less than 30%, the deposition process comprising a pulsed delivery flow of a hard mask precursor to the deposition chamber with a duty cycle of less than 100%;
and,
treating the deposited film with a plasma, during a time when the precursor flow is off.

1 more element

Dependencies are inferred from the claim text.

Pulsed PECVD method for modulating hydrogen content in hard mask

Life of this patent

Pulsed PECVD method for modulating hydrogen content in hard mask

Life of this patent

Abstract

Claims31