Two-dimensional (2-D) doping profiles of differently doped Si homostructures were investigated by scanning capacitance microscopy (SCM) and scanning Kelvin probe microscopy (SKPM). The calibrated doping concentration of the n-step Si layers was in the range of 4.2e14 ~ 1.7e19 cm-3. In SCM, measured dC/dV signals were converted to 2-D doping concentrations using the NIST FASTC2D program. To compare the SCM-based 2-D dopant profiles with those obtained by SKPM, a contact potential difference (CPD) between a probe tip and the Si sample surface was measured in SKPM. Using the relation between a work function and a doping concentration of Si, the doping concentrations were extracted from the measured CPD. Initial SCM results had good agreements with the calibrated data, but the SKPM results showed little difference due to the presence of the top native oxide layer and the superposition between neighbor potentials.
Conference Dates: June 5-8, 2005
Conference Location: Daytona Beach, FL
Conference Title: Ultra Shallow Junction 2005
Pub Type: Conferences
Doping density, Potential, Scanning capacitance microscopy, Scanning Kelvin probe microscopy