Dry Etching Characteristics of GaN using a Magnetized Inductively Coupled $CH_4/H_2/Ar$ Plassma

자화 유도 결합형 $CH_4/H_2/Ar$ 플라즈마를 이용한 GaN 건식 식각 특성

  • 김문영 (경북대 전자전기공학부 대학원) ;
  • 심종경 (경북대 전자전기공학부 석사) ;
  • 태흥식 (경북대 전자전기공학부) ;
  • 이호준 (위덕대 전기공학과) ;
  • 이용현 (경북대 전자전기공학부 정) ;
  • 이정희 (경북대 전자전기공학부) ;
  • 백영식 (경북대 전자전기공학부 정)
  • Published : 2000.04.01

Abstract

This paper proposes the improvement of the etch rate of GaN using a magnetized inductively coupled $CH_4/H_2/Ar$plasma. The gradient magnetic field with the axial direction is investigated using Gauss-meter and the ion current density is measured using double Langmuir probe. The applied magnetic field changes the ion current density profile in the radial direction, resulting in producing the higher density in the outer region than in the center. GaN dry etching process is carried out based on the measurements of the ion current density. The each rate of 2000 /min is achieved with $CH_4/H_2/Ar$ chemistries at 800 W input power, 250W rf bias power, 10 mTorr pressure and 100 gauss magnetic field.

Keywords

a magnetized inductively coupled $CH_4/H_2/Ar$ plasma;ion current density;GaN;dry etching;etch rate

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