METHOD FOR GROWING HEMISPHERICAL GRANULAR SILICON

摘要

PROBLEM TO BE SOLVED: To provide a method for forming an integrated circuit device incorporating a conductor having irregular surface. SOLUTION: Hemispherical granular silicon(HSG-Si) is deposited on a polysilicon by plasma deposition. In the plasma deposition of HSG-Si, the substrate deposition 42 temperature can be set over a wide range as compared with low pressure chemical vapor deposition(LPCVD). Plasma deposition of HSG-Si is performed in an electron cyclotron resonance chemical vapor deposition(ECR-CVD) system at an input power level of 100-1500W, a total pressure of 5-60mTorr, and a substrate 42 temperature of 600 deg.C or below. A mixture of silane and hydrogen gas (H2 /SiH4 +H2 ) where the dilution ratio of hydrogen is 70-99% is employed in the ECR-CVD system. Native oxide is cleaned off from the polysilicon surface prior to plasma deposition of HSG-Si.