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:
performing a main etch step on the basis of a main etch plasma atmosphere so as to form an opening in a dielectric material of a metallization system of a semiconductor device; and performing a plurality of over-etch steps on the basis of an over-etch plasma atmosphere, each of said plurality of over-etch steps comprising an increase of electromagnetic power of a first radio frequency and an increase of electromagnetic power of a second radio frequency, in each over-etch step, wherein a first rate of increase of electromagnetic power of said first radio frequency is greater than a second rate of increase of electromagnetic power of said second radio frequency, said first radio frequency being higher than said second radio frequency.