Fabrications and Analysis of Schottky Diode of Silicon Carbide Substrate with novel Junction Electric Field Limited Ring

새로운 전계 제한테 구조를 갖는 탄화규소 기판의 쇼트키 다이오드의 제작과 특성 분석

  • Published : 2006.07.01

Abstract

We have used the silicon-carbide(4H-SiC) instead of conventional silicon materials to develope of the planar junction barrier schottky rectifier for ultra high breakdown voltage(1,200 V grade). The substrate size is 2 inch wafer, Its concentration is $3*10^{18}/cm^{3}$ of $n^{+}-$type, thickness of epitaxial layer $12{\mu}m$ conentration is $5*10^{15}cm^{-3}$ of n-type. The fabticated devices are junction barrier schottky rectifier, The guard ring for improvement of breakdown voltage is designed by the box-like impurity of boron, the width and space of guard ring was designed by variation. The contact metals to rectify were used by the $Ni(3,000\:{\AA})/Au(2,000\:{\AA})$. As a results, the on-state voltage is 1.26 V, on-state resistance is $45m{\Omega}/cm^{3}$, maximum value of improved reverse breakdown voltage is 1180V, reverse leakage current density is $2.26*10^{-5}A/CM^{3}$. We had improved the measureme nt results of the electrical parameters.

초고내압용 (1,200 V급) 의 플래너 접합 장벽 쇼트키 정류기 개발을 위해서 기존의 실리콘 재질 대신에 탄화규소 (4H-SiC) 제질을 사용하였다 . 기판의 크기는 2 인치 웨이퍼이며, 농도는 $3*10^{18}/cm^{3}$$n^{+}-$형이며, 에피층은 두께 $12{\mu}m$, 농도는 $5*10^{15}/cm^{-3}\:n-$형이다. 제작 소자는 접합 장벽 쇼트키 다이오드이며, 항복전압을 개선시키기 위해 고농도 의 보론 보호테의 불순물 분포를 사각모양 설계하였으며, 보호태의 폭과 간격을 변화하였다 . 정류성 접촉 금속은 $Ni(3,000\:{\AA})/Au(2,000\:{\AA})$ 사용하였다 . 결과로써, 소자의 특성은 온-상태 전압이 1.26 V, 온-상태 저항은 m$45m{\Omega}/cm^{3}$으로 낮은 특성과역방향 항복전압은 1,180 V의 최대값이며, 이 항복전압의 역방향 누설전류밀도는 $2.26*10^{-5}A/CM^{3}$의 값이며, 전기적 파라미터의 특성 결과가 개선되었다.

Keywords

References

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