Using SuperScan™ and SuperScan II™ to improve Vt variations in a p-channel power MOSFET device

SuperScan™ and SuperScan II™, software add-on programs that can be used with AMAT VIISta medium current implanters, have been used to improve center-to-edge Vt variations in a power device. By using SuperScan™ for implanting an n-type doped body implant, an improvement has been seen in radial, center-to-edge Vt variations by up to 32% (ΔVt = 170mV) compared to implanting without SuperScan™ (ΔVt = 250mV). However, if the Vt non-uniformity pattern is slightly off-center, the correction in Vt variation may be better suited for the use of SuperScan II™, which can implant radial patterns which are off-center. An improvement of up to 64% (ΔVt = 90mV) has been seen in center-to-edge Vt variations for off-center patterns by using SuperScan II™ for implanting the same n-type doped body implant.