The new generation of the photoelectric measurement methods of mos structure parameters

Abstract

New generation of MOS (metal-oxide-semiconductor) system photoelectric measurement methods has been developed. These methods are based on a new approach to the photoelectric phenomena occurring at low electric fields in the dielectric layer. Basic features of this approach were outlined, with the emphasis on its practical applications. Principles underlying some of the new measurement methods were presented, underscoring the importance of the effective contact potential difference (ECPD or PhiMS) determination method. This method is the most sensitive and accurate of the existing methods of PhiMS determination. These measurement methods have been recently improved, allowing for the first time, to determine distributions of local PhiMS values over the gate area of MOS structures. Distributions of PhiMSvalues were determined for metal-gate and silicon-gate MOS structures. Comparison of the results obtained was presented. Methods were also developed to determine distributions of potential barrier height local values at gate-dielectric and semiconductor-dielectric interfaces. Examples of such distributions were given and their causes, as well as consequences were discussed