Electron beam assisted platinum film deposition has been found to be an effective method to protect the sample surface for both FIB and TEM analysis. In this paper, the phenomena of electron beam assisted deposition of platinum will be reviewed The results suggest that a 45 nm thick residual Pt film can effectively protects (100) silicon from damage induced by ion beam assisted Pt deposition. A carbon based organic layer under the electron beam assisted Pt has been observed. The mechanism and results on exposed oxide thickness measurements will be discussed. It is suggested that a carbon glue cap be used as a protective layer or polysilicon be deposited in line before submitting the wafer for TEM sample preparation and observation.