Optimization of the specific on-resistance of the COOLMOS/sup TM/

The optimized values for the physical and geometrical parameters of the p- and n-regions used in the voltage-sustaining layer of the COOLMOS/sup TM/ are presented. Design of the parameters is aimed to produce the lowest specific on-resistance, R/sub on/ for a given breakdown voltage, V/sub B/. A new relationship between the R/sub on/ and V/sub B/ for the COOLMOS/sup TM/ is developed as R/sub on/=C/spl middot/V/sub B//sup 1.32/, where the constant C is dependent on the cell dimension and pattern geometry. It is also found that by putting a thin layer of insulator between the p-region and its neighboring n-regions, the value of R/sub on/ can be further reduced. The possibility of incorporating the insulating layer may open up opportunities for practical implementation of the COOLMOS/sup TM/ for volume production.