Journal of the Korean Crystal Growth and Crystal Technology (한국결정성장학회지)

The Korea Association of Crystal Growth (한국결정성장학회)
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Defects analysis of RE : YAG (RE = Nd3+, Er3+) single crystal synthesized by Czochralski method

Czochralski법으로 성장된 RE : YAG(RE = Nd3+, Er3+) 단결정의 결함분석

  • Park, Cheong Ho (Div. of Materials Engineering & Convergence Technology, Gyeongsang National Univ.) ;
  • Joo, Young Jun (Div. of Materials Engineering & Convergence Technology, Gyeongsang National Univ.) ;
  • Kim, Hye Young (Dept. of Nano & Advanced Materials Engineering, Gyeongsang National Univ.) ;
  • Shim, Jang Bo (Thin Film Materials Research Center, Korea Research Institute of Chemical Technology) ;
  • Kim, Cheol Jin (Research Institute of Green Energy Convergence Technology, Gyeongsang National Univ.)
  • 박청호 (경상대학교 나노신소재융합공학과) ;
  • 주영준 (경상대학교 나노신소재융합공학과) ;
  • 김혜영 (경상대학교 세라믹공학과) ;
  • 심장보 (한국화학연구원 박막재료 연구센터) ;
  • 김철진 (경상대학교 그린에너지융합연구소)
  • Received : 2015.12.28
  • Accepted : 2016.01.29
  • Published : 2016.02.29
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Abstract

RE : YAG ($RE=Nd^{3+}$, $Er^{3+}$) single crystals are laser diodes and generally grown by Czochralski method with controlling the various growth parameter. Since the defects occurred by temperature gradient or the rotation speed of solid-liquid growth interface act as the decline of crystal optical property during the growth procedure, crystalline quality improvement via defects analysis is necessary. The etch pit density (EPD) analysis was used to confirm the surface defect of grown RE : YAG single crystal and to select the area of transmission electron microscopy (TEM) analysis. Defects in the specimen produced by tripod polishing method such as buckling, rod shaped, bend contours by internal stress, segregation and others were observed by using 200 kV TEM and 300 kV FE-TEM.

RE : YAG 단결정은 레이저 발진 소재로 다양한 성장 변수를 제어하면서 Czochralski법으로 성장된다. 성장과정 동안 고액계면의 온도구배 및 회전속도에 의해 발생하는 결함들은 결정의 광학적 특성 저하로 작용하기 때문에 결함 분석을 통한 결정 품질의 향상을 필요로 한다. 격자결함 밀도 분석(EPD)을 통하여 성장된 RE : YAG 단결정의 표면 결함 존재를 확인하였고, 이를 통해 투과전자현미경(TEM) 분석영역을 선택하였다. 선택한 영역의 시편은 트라이포드 연마 방법으로 제작하였고, 200 kV 투과전자현미경과 300 kV 전계 방사형 투과전자현미경(FE-TEM)을 사용하여 buckling, rod shaped, 내부응력에 의한 bend contours, 편석 등의 결함들을 관찰하였다.

Keywords

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