CHEMISORPTION OF BA ON DEUTERIUM-TERMINATED SI(100) SURFACE

The system of Ba overlayers deposited on a deuterium-terminated Si(100 ) surface was investigated by means of MDS (metastable de-excitation s pectroscopy) and TDS (thermal desorption spectroscopy). Deposition of Ba overlayers caused the reduction of Si-D bond strength because of ch arge donation to Si substrate from Ba atoms. The other half reacted wi th adsorbed Ba atoms entirely to form Ba-D bonds. Therefore, all the S i-D bonds were lost, which is quite different from the alkali/D/Si(100 ) system. More Ba deposition did not induce the desorption of D atoms. The formed Ba-D bonds are considered to stay between the first and se cond layer.