Two-dimensional impurity profiling near the mask edge using anodisation

An experimental scheme for measuring the two-dimensional impurity profile near the mask edge is described, based on forming a U-groove in silicon by anisotropic etching leaving only the sidewall resistors. 2-D impurity profiling of the sidewall resistor is achieved by constant-voltage anodisation and etching the resultant oxide. An n × m resistor array structure for simultaneously obtaining the 2-D impurity profile is also described.