On-line capacitance—Voltage doping profile measurement of low-dose ion implants

An on-line computer-controlled measurement system gathers and analyzes 1-MHz capacitance-voltage data for ion-implanted MOS structures. The analysis algorithm takes into account the majority-carrier distribution for depletion-region widths of less than two Debye lengths and is, therefore, valid for implant profile measurements up to the semiconductor-oxide interface. data and implant profiles are presented for low-dose implants in the 10¹¹-10¹²-cm^-2range. The measurement technique is a sensitive indicator of low-dose implant distribution and may be used in the process control of MOSFET threshold-adjusting implants and other low-dose implant applications.