PLASMA-ASSISTED SURFACE MODIFICATION AND RADICAL DIAGNOSTICS

Plasma-assisted deposition and etching have widely been applied to microelectronics devices in industries as well as to huge vacuum devices in nuclear fusion. A more detailed understanding of plasma processing is essential for development of new techniques for small-scale (< 1/4 mum) etching and large-scale ( > 10 m) deposition. A scaling law for uniformity of large-scale deposition was found in a simulation experiment of boron coating of fusion devices, using a less hazardous boride B10H14 (decaborane). Moreover, boron etching by a fluorocarbon plasma was demonstrated along with a new modeling of surface-coverage effects. Appearance mass spectrometry which is a powerful tool for neutral radical detection, has successfully been applied to a CF4 containing RF plasma for semiconductor etching. Addition of a small amount of H-2 into CF4 drastically modified the kinetics of CF2 and CF3 radicals as a result of surface processes.