Advertisement

Photoelectrochemically combined mechanical polishing of n-type gallium nitride wafer by using metal nanoparticles as photocathodes

  • Liwei Ou
  • Zhigang Dong
  • Renke KangEmail author
  • Kang ShiEmail author
  • Dongming Guo
ORIGINAL ARTICLE

Abstract

In this study, we developed a photoelectrochemically combined mechanical polishing (PECMP) method to process n-type gallium nitride (GaN) wafer. The methodological features include (1) the pre-adsorption of metal nanoparticles (MNPs) within the polishing pad; (2) the use of ultraviolet (UV)-light to irradiate the wafer under the polishing solution containing oxidizing reagents and abrasives. During polishing, a tight contacting between MNPs and newly exposed GaN surface may construct a photoelectrochemical (PEC) circuit, similar as a solar cell system. In terms of PEC oxidation/etching mechanism, MNPs with a suitable work function can act as the photocathodes to facilitate the extraction of the photogenerated conduction band (CB) electrons of GaN by the oxidizing agents; thus, the photogenerated valence band (VB) holes may oxidize the GaN surface. We designed a novel equipment to enable the alternating of GaN wafer between PEC oxidation and mechanical polishing. Results show that when PECMP employing gold (Au) MNPs and 0.18 wt% SiO2 abrasives, the fastest material removal rate (MRR) attains 198.6 nm/h and the surface roughness (Ra) reaches 1.55 nm (5 × 5 μm2). PECMP has the distance-sensitive material removal ability due to the higher polishing pressure generated at the tops of rough surface, at which the tighter MNP-GaN contact causes the faster PEC oxidation. The presented results reveal that PECMP is a promising approach to polish inert semiconductors in high efficiency and high quality.

Keywords

Gallium nitride Photoelectrochemically combined mechanical polishing Metal nanoparticles Material removal rate Chemical mechanical polishing 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Notes

Funding information

This work received financial support from the National Natural Science Foundation of China (No. 51575085, 91523102, 21273183, 21621091), the National key Research and Development Program of China (Grant No.2016YFB1102205), and the National Science and Technology Major Project of China (Grant No. 2014ZX02504001004).

References

  1. 1.
    Xu X, Vaudo RP, Brandes GR (2003) Fabrication of GaN wafers for electronic and optoelectronic devices. Opt Mater 23:1–5.  https://doi.org/10.1016/S0925-3467(03)00051-X CrossRefGoogle Scholar
  2. 2.
    Pearton SJ, Zolper JC, Shul RJ, Ren F (1999) GaN: processing, defects, and devices. J Appl Phys 86:1–78.  https://doi.org/10.1063/1.371145 CrossRefGoogle Scholar
  3. 3.
    Fujii K, Karasawa K, Ohkawa K (2005) Hydrogen gas generation by splitting aqueous water using n-type GaN photoelectrode with anodic oxidation. Jpn J Appl Phys 44:L543–L545.  https://doi.org/10.1143/JJAP.44.L543 CrossRefGoogle Scholar
  4. 4.
    Ebrahimi M, Hanzaki AZ, Abedi HR, Azimi M, Mirjavadi SS (2017) Correlating the microstructure to mechanical properties and wear behavior of an accumulative back extruded Al-Mg2Si in-situ composite. Tribol Int 115:199–211.  https://doi.org/10.1016/j.triboint.2017.05.034 CrossRefGoogle Scholar
  5. 5.
    Cheng K, Huo D (2013) Micro cutting: fundamentals and applications. Wiley, ChichesterCrossRefGoogle Scholar
  6. 6.
    Hoseinlaghab S, Mirjavadi SS, Sadeghian N, Jalili I, Azarbarmas M, Besharati Givi MK (2015) Influences of welding parameters on the quality and creep properties of friction stir welded polyethylene plates. Mater Des 67:369–378.  https://doi.org/10.1016/j.matdes.2014.11.039 CrossRefGoogle Scholar
  7. 7.
    Zhao D, Lu X (2013) Chemical mechanical polishing: theory and experiment. Friction 1:306–326.  https://doi.org/10.1007/s40544-013-0035-x CrossRefGoogle Scholar
  8. 8.
    Luo JF, Dornfeld DA (2001) Material removal mechanism in chemical mechanical polishing: theory and modeling. IEEE Trans Semicond Manufact 14:112–133.  https://doi.org/10.1109/66.920723 CrossRefGoogle Scholar
  9. 9.
    Kasai T, Bhushan B (2008) Physics and tribology of chemical mechanical planarization. J Phys Condens Mat 20:1–13.  https://doi.org/10.1088/0953-8984/20/22/225011 CrossRefGoogle Scholar
  10. 10.
    Aida H, Takeda H, Koyama K, Katakura H, Sunakawa K, Doi T (2011) Chemical mechanical polishing of gallium nitride with colloidal silica. J Electrochem Soc 158:H1206–H1212.  https://doi.org/10.1149/2.024112jes CrossRefGoogle Scholar
  11. 11.
    Gong H, Pan G, Zhou Y, Shi X, Zou C, Zhang S (2015) Investigation on the surface characterization of Ga-faced GaN after chemical-mechanical polishing. Appl Surf Sci 338:85–91.  https://doi.org/10.1016/j.apsusc.2015.02.107 CrossRefGoogle Scholar
  12. 12.
    Deng H, Endo K, Yamamura K (2015) Plasma-assisted polishing of gallium nitride to obtain a pit-free and atomically flat surface. Ann CIRP Manuf Technol 64:531–534.  https://doi.org/10.1016/j.cirp.2015.04.002 CrossRefGoogle Scholar
  13. 13.
    Wang J, Wang T, Pan G, Lu X (2015) Mechanism of GaN CMP based on H2O2 slurry combined with UV light. ECS J Solid State Sci Technol 4:P112–P117.  https://doi.org/10.1149/2.0191503jss CrossRefGoogle Scholar
  14. 14.
    Shi X, Zou C, Pan G, Gong H, Xu L, Zhou Y (2017) Atomically smooth gallium nitride surface prepared by chemical mechanical polishing with S2O8 2--Fe2+ based slurry. Tribol Int 110:441–450.  https://doi.org/10.1016/j.triboint.2016.09.037 CrossRefGoogle Scholar
  15. 15.
    Minsky MS, White M, Hu EL (1996) Room-temperature photoenhanced wet etching of GaN. Appl Phys Lett 68:1531–1533.  https://doi.org/10.1063/1.115689 CrossRefGoogle Scholar
  16. 16.
    Bardwell JA, Webb JB, Tang H, Fraser J, Moisa S (2001) Ultraviolet photoenhanced wet etching of GaN in K2S2O8 solution. J Appl Phys 89:4142–4149.  https://doi.org/10.1063/1.1352684 CrossRefGoogle Scholar
  17. 17.
    Zhang M, Hou F, Wang Z, Zhang S, Pan G (2017) Photoelectrochemical etching of gallium nitride surface by complexation dissolution mechanism. Appl Surf Sci 410:332–335.  https://doi.org/10.1016/j.apsusc.2017.03.063 CrossRefGoogle Scholar
  18. 18.
    Zhuang D, Edgar JH (2005) Wet etching of GaN, AlN, and SiC: a review. Mater Sci Eng R 48:1–46.  https://doi.org/10.1016/j.mser.2004.11.002 CrossRefGoogle Scholar
  19. 19.
    Dogliotti L, Hayon E (1967) Flash photolysis of persulfate ions in aqueous solutions study of the sulfate and ozonide radical anions. J Phys Chem 71:2511–2516.  https://doi.org/10.1021/j100867a019 CrossRefGoogle Scholar
  20. 20.
    Gao Y, Gao N, Deng Y, Yang Y, Ma Y (2012) Ultraviolet (UV) light-activated persulfate oxidation of sulfamethazine in water. Chem Eng J 248:248–253.  https://doi.org/10.1016/j.cej.2012.04.084 CrossRefGoogle Scholar
  21. 21.
    Peyton GR (1993) The free-radical chemistry of persulfate-based total organic carbon analyzers. Mar Chem 41:91–103.  https://doi.org/10.1016/0304-4203(93)90108-Z CrossRefGoogle Scholar
  22. 22.
    Adewuyi YG (2005) Sonochemistry in environmental remediation. 2. Heterogeneous sonophotocatalytic oxidation processes for the treatment of pollutants in water. Environ Sci Technol 39:8557–8570.  https://doi.org/10.1021/es0509127 CrossRefGoogle Scholar
  23. 23.
    van Dorp DH, Weyher JL, Kooijman MR, Kelly JJ (2009) Photoetching mechanisms of GaN in alkaline S2O8 2- solution. J Electrochem Soc 156:D371–D376.  https://doi.org/10.1149/1.3183807 CrossRefGoogle Scholar
  24. 24.
    Sell K, Barke I, Polei S, Schumann C, von Oeynhausen V, Meiwes-Broer K (2010) Surface photovoltage of Ag nanoparticles and Au chains on Si(111). Phys Status Solidi B 247:1087–1094.  https://doi.org/10.1002/pssb.200945577 CrossRefGoogle Scholar
  25. 25.
    Zhang Z, Yates JT (2012) Band bending in semiconductors: chemical and physical consequences at surfaces and interfaces. Chem Rev 112:5520–5551.  https://doi.org/10.1021/cr3000626 CrossRefGoogle Scholar
  26. 26.
    Schäfer S, Koch AHR, Cavallini A, Stutzmann M, Sharp ID (2012) Charge transfer across the n-Type GaN-electrolyte interface. J Phys Chem C 116:22281–22286.  https://doi.org/10.1021/jp302000x CrossRefGoogle Scholar
  27. 27.
    Miura N, Nanjo T, Suita M, Oishi T, Abe Y, Ozeki T, Ishikawa H, Egawa T, Jimbo T (2004) Thermal annealing effects on Ni/Au based schottky contacts on n-GaN and AlGaN/GaN with insertion of high work function metal. Solid-State Electr 48:689–695.  https://doi.org/10.1016/j.sse.2003.07.006 CrossRefGoogle Scholar
  28. 28.
    Weyher JL, Tichelaar FD, Zandbergen HW, Macht L, Hageman PR (2001) Selective photoetching and transmission electron microscopy studies of defects in heteroepitaxial GaN. J Appl Phys 90:6105–6109.  https://doi.org/10.1063/1.1416137 CrossRefGoogle Scholar
  29. 29.
    Youtsey C, Romano LT, Molnar RJ, Adesida I (1999) Rapid evaluation of dislocation densities in n-type GaN films using photoenhanced wet etching. Appl Phys Lett 74:3537–3539.  https://doi.org/10.1063/1.124153 CrossRefGoogle Scholar
  30. 30.
    Youtsey C, Romano LT, Adesida I (1998) Gallium nitride whiskers formed by selective photoenhanced wet etching of dislocations. Appl Phys Lett 73:797–799.  https://doi.org/10.1063/1.122005 CrossRefGoogle Scholar
  31. 31.
    Murata J, Sadakuni S (2015) Photo-electrochemical etching of free-standing GaN wafer surfaces grown by hydride vapor phase epitaxy. Electrochim Acta 171:89–95.  https://doi.org/10.1016/j.electacta.2015.04.166 CrossRefGoogle Scholar
  32. 32.
    Liu L, Edgar JH (2002) Substrates for gallium nitride epitaxy. Mater Sci Eng R 37:61–127.  https://doi.org/10.1016/S0927-796X(02)00008-6 CrossRefGoogle Scholar
  33. 33.
    Detchprohm T, Xia Y, Xi Y, Zhu M, Zhao W, Li Y, Schubert EF, Liu L, Tsvetkov D, Hanser D, Wetzel C (2007) Dislocation analysis in homoepitaxial GaInN/GaN light emitting diode growth. J Cryst Growth 298:272–275.  https://doi.org/10.1016/j.jcrysgro.2006.10.129 CrossRefGoogle Scholar
  34. 34.
    Kim HM, Oh JE, Kang TW (2001) Preparation of large area free-standing GaN substrates by HVPE using mechanical polishing liftoff method. Mater Lett 47:276–280.  https://doi.org/10.1016/S0167-577X(00)00249-4 CrossRefGoogle Scholar

Copyright information

© Springer-Verlag London Ltd., part of Springer Nature 2019

Authors and Affiliations

  1. 1.Institute of Advanced Manufacturing Technology, School of Mechanical EngineeringDalian University of TechnologyDalianPeople’s Republic of China
  2. 2.Department of Chemistry and State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical EngineeringXiamen UniversityXiamenPeople’s Republic of China

Personalised recommendations