High voltage semiconductor device having high breakdown voltage and method of fabricating the same

Abstract

A high voltage semiconductor device, including: a high concentration collector area of a first conductive type; a low concentration collector area of a first conductive type formed on the high concentration collector area; a base area of a second conductive type formed on the low concentration collector area and having a trench perforating the low concentration collector area in a vertical direction at the edge of the trench; a high concentration emitter area of a first conductive type formed on a predetermined upper surface of the base area; and an emitter electrode, a base electrode, and a collector electrode isolated from one another and connected to the emitter area, the base area, and the collector area, respectively. High breakdown voltage can be obtained with a narrow junction termination area due to the trench.

What is claimed is:  
     
         1 . A high voltage semiconductor device, comprising: 
 a high concentration collector area of a first conductive type;    a low concentration collector area of a first conductive type formed on the high concentration collector area;    a base area of a second conductive type formed on the low concentration collector area and having a trench which penetrates the low concentration collector area in a vertical direction at the edge of the trench;    a high concentration emitter area of a first conductive type formed on a predetermined upper surface of the base area; and    an emitter electrode, a base electrode, and a collector electrode isolated from one another and connected to the emitter area, the base area, and the collector area, respectively.    
     
     
         2 . The high voltage semiconductor device of  claim 1 , wherein the width of the trench is {fraction (1/10)} times the depth of the trench.  
     
     
         3 . The high voltage semiconductor device of  claim 1 , further comprising an oxide layer which fills the trench.  
     
     
         4 . A method of fabricating a high voltage semiconductor device, comprising: 
 preparing a semiconductor substrate having a high concentration collector area and a low concentration collector area of a first conductive type;    forming a base area of a second conductive type on the low concentration collector area;    forming a high concentration emitter area of a first conductive type on a predetermined upper portion of the base area;    forming a trench penetrating the base area and the low concentration collector area at the edge of the base area, spaced apart from the emitter area; and    forming an emitter electrode, a base electrode, and a collector electrode connected to the emitter area, the base area, and a semiconductor substrate, respectively.    
     
     
         5 . The method of  claim 4 , wherein the trench is formed using a reactive ion etching method.  
     
     
         6 . The method of  claim 5 , wherein the reactive ion etching is performed using Cl 2  or SF 6  as a reaction gas.  
     
     
         7 . The method of  claim 4 , wherein the width of the trench is {fraction (1/10)} times the depth of the trench.