DOI QR코드

DOI QR Code

Characterization of GaN epitaxial layer grown on nano-patterned Si(111) substrate using Pt metal-mask

Pt 금속마스크를 이용하여 제작한 나노패턴 Si(111) 기판위에 성장한 GaN 박막 특성

  • Kim, Jong-Ock (School of Semiconductor and Chemical Engineering, Semiconductor Physics Research Center, Chonbuk National University) ;
  • Lim, Kee-Young (School of Semiconductor and Chemical Engineering, Semiconductor Physics Research Center, Chonbuk National University)
  • 김종옥 (전북대학교 반도체 화학공학부, 반도체 물성 연구소) ;
  • 임기영 (전북대학교 반도체 화학공학부, 반도체 물성 연구소)
  • Received : 2013.06.24
  • Accepted : 2014.09.18
  • Published : 2014.09.30

Abstract

An attempt to grow high quality GaN on silicon substrate using metal organic chemical vapor deposition (MOCVD), herein GaN epitaxial layers were grown on various Si(111) substrates. Thin Platinum layer was deposited on Si(111) substrate using sputtering, followed by thermal annealing to form Pt nano-clusters which act as masking layer during dry-etched with inductively coupled plasma-reactive ion etching to generate nano-patterned Si(111) substrate. In addition, micro-patterned Si(111) substrate with circle shape was also fabricated by using conventional photo-lithography technique. GaN epitaxial layers were subsequently grown on micro-, nano-patterned and conventional Si (111) substrate under identical growth conditions for comparison. The GaN layer grown on nano-patterned Si (111) substrate shows the lowest crack density with mirror-like surface morphology. The FWHM values of XRD rocking curve measured from symmetry (002) and asymmetry (102) planes are 576 arcsec and 828 arcsec, respectively. To corroborate an enhancement of the growth quality, the FWHM value achieved from the photoluminescence spectra also shows the lowest value (46.5 meV) as compare to other grown samples.

본 연구에서는 Si(111) 기판을 이용하여 고품질의 GaN 박막을 성장하기 위하여 다양한 패턴을 갖는 Si 기판을 제작하였다. Si(111) 기판위에 이온 스퍼터(ion-sputter)를 이용하여 Pt 박막을 증착한 후 열처리(thermal annealing)하여 Pt 금속 마스크를 형성하고 유도 결합 플라즈마 이온 식각(inductively coupled plasma-reactive ion etching, ICP-RIE) 공정을 통하여 기둥(pillar)형태의 나노 패턴된 Si(111) 기판을 제작하였고 리소그래피 공정을 통하여 마이크로 패턴된 Si(111) 기판을 제작하였다. 일반적인 Si(111) 기판, 마이크로 패턴된 Si(111) 기판 및 나노 패턴된 Si(111) 기판위에 유기화학기상증착(metal organic chemical vapor deposition, MOCVD) 방법으로 GaN 박막을 성장하여 표면 특성과 결정성 및 광학적 특성을 분석하였다. 나노 패턴된 Si(111) 기판위에 성장한 GaN 박막은 일반적인Si(111) 기판과 마이크로 패턴된 Si(111) 기판위에 성장한 GaN 박막보다 표면의 균열과 거칠기가 개선되었다. 나노 패턴된 Si(111) 기판위에 성장한 GaN (002)면과 (102)면에 x-선 회절(x-ray diffraction, XRD) 피크의 반폭치(full width at half maximum, FWHM)는 576 arcsec, 828 arcsec으로 다른 두 기판위에 성장한 GaN 박막 보다 가장 낮은 값을 보여 결정성이 향상되었음을 확인하였다. Photoluminescence(PL)의 반폭치는 나노 패턴된 Si(111) 기판위에 성장한 GaN 박막이 46.5 meV으로 다른 기판위에 성장한 GaN 박막과 비교하여 광학적 특성이 향상되었음을 확인하였다.

Keywords

References

  1. S. Strite and H. Morkoc, "GaN, AlN, and InN: A review", J. Vac. Sci. Technol. B. 10(4), 1237 (1992). https://doi.org/10.1116/1.585897
  2. T. Tetsuya, T. Hideo, S. Shigetoshi and S. Hiromitsu, "Optcial Properties of Strained AlGaN and GaInN on GaN", Jpn. J. Appl. Phys. 36(2B), L177 (1997). https://doi.org/10.1143/JJAP.36.L177
  3. S. Nakamura, M. Senoh, S. Nagahama, N. Iwasa, T. Yamada, T. Matsushita H. Kiyoku and Y. Sugimoto, "InGaN-Based Multi-Quant$\mu$m-Well-Structure Laser Diodes", Jpn. J. Appl. Phys. 35(1B), L74 (1996). https://doi.org/10.1143/JJAP.35.L74
  4. R. Chu, Z. Chen and Y. Pei, "MOCVD-Grown AlGaN Buffer GaN HEMTs With V-Gates for Microwave Power Applications", IEEE Trans. Electron Devices. 30(9), 910 (2009). https://doi.org/10.1109/LED.2009.2026659
  5. S. C. Jain, M. Willander, J. Narayan and R. Van Overstraeten, "III-nitrides: Growth, characterization, and properties", J. Appl. Phys. 87(3), 965 (2000). https://doi.org/10.1063/1.371971
  6. J. Park, M. W. Shin and C. C. Lee, "Measurement of temperature profiles on visible light-emitting diodes by use of a nematic liquid crystal and an infrared laser", Optics Lett. 29(22), 2657 (2004).
  7. L. Kim and M. W. Shin, "Thermal Resistance Measurement of LED Package with Multichips", IEEE Trans. Compon Packag Tech. 30(4), 632 (2007). https://doi.org/10.1109/TCAPT.2007.906332
  8. H. J. Kang, H. Y. Song and M. Y. Jeong, "Design of Structure for High-Efficiency LEDs On Patterned Sapphire SubStrate", J. Microelectron. Packag. Soc., 18(4), 91 (2011).
  9. B. K. Yu, M. Y. Kim and T. S. Oh, "Anisotropic Wet-Etching Process Of Si substrate for Formation of Thermal Vias in High-Power LED Packages", J. Microelectron. Packag. Soc., 19(4), 51 (2012). https://doi.org/10.6117/kmeps.2012.19.4.051
  10. A. Dadgar, M. Poschenrieder, J. Blasing, O. Contreras, F. Bertram, T. Riemann, A. Reiher, M. Kunze, I. Da$\mu$miller, A. Krtschil, A. Diez, A. Kaluza, A. Modlich, M. Kamp, J. Christen, F. A. Ponce, E. Kohn and A. Krost, "MOVPE growth of GaN on Si(111) substrates", J. Cryst. Growth. 248, 556 (2003). https://doi.org/10.1016/S0022-0248(02)01894-8
  11. X. Zhang, S. J. Chua, P. Li, K. B. Chong and Z. C. Feng, "Enhanced optical emission from GaN films grown on a silicon substrate", Appl. Phys. Lett. 74(14), 1984 (1999). https://doi.org/10.1063/1.123721
  12. A. Dadgar, J. Blaing, A. Diez and A. Krost, "Crack-Free, Highly Conducting GaN layers on Si Substrates by Ge Doping", Appl. Phys. Ex., 4, 011001 (2011). https://doi.org/10.1143/APEX.4.011001
  13. A. Reiher, J. Bläsing, A. Dadgar, A. Diez and A. Krost, "Efficient stress relief in GaN heteroepitaxy on Si(111) using lowtemperature AlN interlayers", J. Cryst. Growth. 248, 563 (2003). https://doi.org/10.1016/S0022-0248(02)01880-8
  14. H. Ishikawa, K. Shimanaka, M. Azfar bin, M Amir, Y. Hara and M. Nakanishi, "Improved MOCVD growth of GaN on Sion- porous-silicon substrates", Phys. Stat. Sol(C). 7(7), 2049 (2010). https://doi.org/10.1002/pssc.200983496
  15. L. S. Wang, S. J. Chua, S. Tripathy, K. Y. Zang, B. Z. Wang and J. H. Teng, "Nanopatterning and selective area epitaxy of GaN on Si substrate", Proc. of SPIE., 6894, 68940 (2008).
  16. C. C. Huang, S. J. Chang, C. H. Kuo, C. H. Wu, C. H. Ko, H. Wann, Y. C. Cheng and W. J. Lin, "Single Crystalline GaN Epitaxial Layer Prepared on Nano-patterned Si(001) Substrate", J. Electrochem. Soc. 158(6), H626 (2011) https://doi.org/10.1149/1.3569753
  17. S. Pal and C. Jacon, "Silicon-a new substrate for GaN growth", Bull. Mater. Sci. 27(6), 501 (2004). https://doi.org/10.1007/BF02707276
  18. S. D. Hersee, X. Y. Sun, X. Wang and M. N. Fairchild, "Nanoheteroepitaxial growth of GaN on Si nanopillar arrays", Appl. Phys. Lett., 97, 124308 (2005).
  19. Y. Li, S. You, M. Zhu, L. Zhao and W. Hou, "Defect-reduced green GaInN/GaN light-emitting diode on nanopatterned sapphire", Appl. Phys. Lett., 98, 151102 (2011). https://doi.org/10.1063/1.3579255
  20. J. Elsner and R. Jones, "Theory of Threading Edge and Screw Dislocation in GaN", Phys. Rev. Lett., 79(19), 3672 (1997). https://doi.org/10.1103/PhysRevLett.79.3672
  21. H. Ishikawa, G. Y. Zhao, N. Nakada, T. Egawa, T. Jimbo and M. umeno, "GaN on Si substrate with AlGaN/AIN Intermediate Layer", Jpn. J. Appl. Phys., 38(5A), L492 (1999). https://doi.org/10.1143/JJAP.38.L492
  22. Josh Abell and T. D. Moustakas, "The role of dislocations as nonradiative recombination center in InGaN quantum wells", Appl. Phys. Lett., 92, 091901 (2008). https://doi.org/10.1063/1.2889444