An Analysis on Optimal Design and Electrical Characteristics of CT-IGBT(Circular Trench IGBT)

CT-IGBT의 최적 설계 및 전기적 특성에 관한 분석

  • Kwak, Sang-Hyeon (Department of Electrical Engineering, Korea University) ;
  • Seo, Jun-Ho (Department of Electrical Engineering, Korea University) ;
  • Seo, In-Kon (Department of Electrical Engineering, Korea University) ;
  • Sung, Man-Young (Department of Electrical Engineering, Korea University)
  • 곽상현 (고려대학교 전기공학과) ;
  • 서준호 (고려대학교 전기공학과) ;
  • 서인곤 (고려대학교 전기공학과) ;
  • 성만영 (고려대학교 전기공학과)
  • Published : 2008.11.06

Abstract

The conventional IGBT has two problems to make the device taking high performance. The one is high on state voltage drop associated with JFET region, the other is low breakdown voltage associated with concentrating the electric field on the junction of between p base and n drift. This paper is about the structure to effectively improve both the lower on state voltage drop and the higher breakdown voltage than the conventional IGBT. For the fabrication of the circular trench IGBT with the circular trench layer, it is necessary to perform the only one wet oxidation step for the circular trench layer. Analysis on both the on state voltage drop and the Breakdown voltage show the improved values compared to the conventional IGBT structure. Because the circular trench layer disperses electric field from p base and n drift junction to circular trench, the breakdown voltage increase. The on state voltage drop decrease due to reduction of JFET region and direction change of current path which pass through reversed layer channel.

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