OPTICAL AND ELECTRICAL-PROPERTIES OF ELECTRON-CYCLOTRON-RESONANCE CHEMICAL-VAPOR-DEPOSITED SINXH FILMS

Silicon nitride (SiN(x):H) films were deposited on both InP and Si sub strates at temperatures ranging from room temperature to 400-degrees-C by electron cyclotron resonance (ECR) plasma chemical-vapour depositi on. The silicon source used was ditertiary butyl silane (SiH2(C4H9)2) that was activated by ECR plasmas composed of nitrogen alone or in com bination with hydrogen or argon. The effects of various deposition par ameters on the film properties are reported. The film indices of refra ction ranged from 1.85 to 2.0, while the buffered HF etch rates were a s low as 6 angstrom min-1 (1 angstrom = 10(-10) m). Si/N ratios of the films ranged from 0.70 to 2.5, while the total hydrogen content was f ound to be approximately 20 to 25 at.%. Incorporation of carbon from t he organic silicon source was efficiently suppressed (< 1%) by the add ition of a small amount of H-2 to the ECR plasma gas. To study the ele ctrical properties of the SiN(x):H films, metal-insulator-semiconducto r structures were fabricated. Film resistivities as high as 2 x 10(15) OMEGA) cm and insulator dielectric constants from 4 to 5 were measure d.