TECHNIQUE FOR REDUCING PLASMA-INDUCED ETCH DAMAGE DURING THE FORMATION OF VIAS IN INTERLAYER DIELECTRICS BY MODIFIED RF POWER RAMP-UP

摘要

When performing plasma assisted etch processes for patterning complex metallization systems of microstructure devices, the probability of creating plasma-induced damage, such as arcing, may be reduced or substantially eliminated by using a superior ramp-up system for the high frequency power and the low frequency power. To this end, the high frequency power may be increased at a higher rate compared to the low frequency power component, wherein, additionally, a time delay may be applied so that, at any rate, the high frequency component reaches its target power level prior to the low frequency component.

主权项

1. A method, comprising:
establishing a first plasma etch atmosphere in a process environment by supplying electromagnetic power of a first radio frequency and electromagnetic power of a second radio frequency to said process environment, said first radio frequency being higher than said second radio frequency; forming an opening in a dielectric layer of a metallization structure of a microstructure device by exposure to said first plasma etch atmosphere, said opening being positioned above a conductive region and extending to a first depth in said dielectric material; at least reducing supply of electromagnetic power of said first and second radio frequencies; establishing a second plasma etch atmosphere in said process environment by increasing electromagnetic power of said first radio frequency within a first time interval and increasing electromagnetic power of said second radio frequency within a second time interval that starts at some point after said first time interval is started; and increasing a depth of said opening so as to extend to a second depth by exposing said dielectric material to said second plasma etch atmosphere.