Real-time in-line testing of semiconductor wafers

An apparatus for measuring damage of an ion implanted semiconductor wafer during semiconductor processing, said apparatus comprising:

• a head assembly comprising a surface photovoltage electrode;
• a conveyer for conveying said wafer such that a surface of said wafer is substantially parallel to said surface photovoltage electrode of said head assembly during said semiconductor processing;
• a light source generating light having a wavelength, and having a maximum intensity, said light source being modulated over a plurality of frequencies up to the maximum intensity, said maximum intensity being insufficient to affect charge distribution in said wafer;
• and
• a detector for detecting with said surface photovoltage electrode a photovoltage induced at the surface of said wafer in response to said light;
• and
• a processor in electrical communication with said detector for calculating an electrical property of said wafer from said photovoltage induced at the surface of said wafer.

A method of measuring damage of an ion implanted semiconductor wafer during semiconductor processing, said method comprising the steps of:

• a) growing an oxide layer on the semiconductor wafer;
• b) performing ion implantation on said wafer;
• c) conveying said wafer such that a surface of said wafer is substantially parallel to a surface photovoltage electrode of a head assembly during said semiconductor processing;
• d) exposing at least a portion of said wafer to light having a wavelength and having a maximum intensity, the light intensity being modulated at a frequency up to the maximum intensity, said maximum intensity being insufficient to affect charge distribution in said wafer;
• e) detecting with said surface photovoltage electrode a photovoltage induced at the surface of said wafer in response to said light;
• f) calculating an electrical property of said wafer from said photovoltage induced at the surface of said wafer, and
• g) repeating steps d–f for a plurality of light intensity modulation frequencies.