SEMICONDUCTOR ELEMENT MANUFACTURING METHOD EMPLOYING COATING AND DIFFUSING METHOD, AND DIODE STRUCTURE

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor element manufacturing method employing a coating and diffusing method which can form a diode of high breakdown voltage in a semiconductor substrate at a low cost, and to provide a diode structure. SOLUTION: A thermal oxidation film 32 containing any one of impurity atoms selected from among phosphorus, arsenic, antimony and boron is coated on at least an Si wafer 31 and baked to form a diffusion source 35, a predetermined quantity of impurity supplied by heating from the diffusion source 35 is diffused in the Si wafer 31, and then, an n+layer 36 as an implantation control layer having the fixed number of impurities is formed by stopping the supply of the impurities by removing the diffusion source 35. An n+layer 36a is formed by re-heating so that the n+layer 36 has a target junction depth and density, and a p++layer 37a is formed on the n+layer 36a by the same method of forming the n+layer 36a. A depth direction junction portion 24 and a bending angle junction portion R on pn structure portions 36a, 37a where polarities become p++n+or n++p+n-in this formation are removed by etching, and the diode is formed. COPYRIGHT: (C)2008,JPO&INPIT