DEVELOPMENT OF A METAL PATTERNED CANTILEVER FOR SCANNING CAPACITANCE MICROSCOPY AND ITS APPLICATION TO THE OBSERVATION OF SEMICONDUCTOR-DEVICES

The performance of scanning capacitance microscopy (SCM) strongly depe nds on the probe used. We have developed an original probe suitable fo r SCM (SCM probe), which uses a pyramid-shaped metal tip and metal lea d line patterned on a silicon nitride cantilever. We installed the SCM probe on a SCM based on a commercial atomic force microscope (AFM). D ifferences in silicon oxide thickness and differences of dopant types and densities in a silicon substrate with a thermal oxide layer were s uccessfully imaged by SCM simultaneously with AFM using the SCM probe. Boundaries between different dopant types and densities, which were n ot recognizable by AFM, were clearly observed by SCM. Signal-to-noise ratio and reproducibility were improved in the SCM images obtained wit h the SCM probe when compared with images obtained with a metal-coated silicon nitride cantilever. (C) 1997 American Vacuum Society. [S0734- 211X(97)04604-0].