SILICON TRENCH ETCHING IN A MULTIFREQUENCY DISCHARGE REACTOR

In this work we investigated dry etching of the trench structures in a gas CCl2F2 in a multi-frequency discharge reactor. The influence of the changes of the etching parameters (low and high frequencies, power and pressure) on the etching process properties (etch rate and selectivity) was investigated. Using a planar diode system with low frequency, 10-100 kHz, applied to the work support and high frequency, 13.56 MHz, to the facing electrode, Si etch rates of 400 nm min-1 were achieved with selectivities of > 100:1 for silicon oxide.