| 摘要 |
PROBLEM TO BE SOLVED: To enhance ESD resistance level by a method wherein the thickness of an N↑- conductivity type layer beneath a P↑+ conductivity type layer is specified, also the specific resistance of the N↑- conductivity type layer is specified. SOLUTION: Within a diode 1 wherein an N↑- conductivity type layer 7 is provided on an N↑+ conductivity type semiconductor substrate 8 so as to form a P↑+ conductivity type layer 6 formed in the layer 7, when the interval between the electrodes 2 and 3 of the diode 1 is inverse-biased, a depletion layer 4 is expanded to the N layer side so as to form the bulk resistance R mainly by the residual N layer. When the specific resistance is whithin the range of 10-25Ω-cm also assuming the thickness of the semiconductor substrate and the N↑- conductivity type layer respectively to be t1 and t2, by designing t1/t2=5.0-54.5 (%), a semiconductor device in ESD resistance level exceeding 30,000 V also in repeated inverse voltage exceeding 400 V can be manufactured, thereby making feasible enhancing the ESD resistance level. |
