Materials (Jul 2020)

Low Temperature Thermal Atomic Layer Deposition of Aluminum Nitride Using Hydrazine as the Nitrogen Source

  • Yong Chan Jung,
  • Su Min Hwang,
  • Dan N. Le,
  • Aswin L. N. Kondusamy,
  • Jaidah Mohan,
  • Sang Woo Kim,
  • Jin Hyun Kim,
  • Antonio T. Lucero,
  • Arul Ravichandran,
  • Harrison Sejoon Kim,
  • Si Joon Kim,
  • Rino Choi,
  • Jinho Ahn,
  • Daniel Alvarez,
  • Jeff Spiegelman,
  • Jiyoung Kim

DOI
https://doi.org/10.3390/ma13153387
Journal volume & issue
Vol. 13, no. 15
p. 3387

Abstract

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Aluminum nitride (AlN) thin films were grown using thermal atomic layer deposition in the temperature range of 175–350 °C. The thin films were deposited using trimethyl aluminum (TMA) and hydrazine (N2H4) as a metal precursor and nitrogen source, respectively. Highly reactive N2H4, compared to its conventionally used counterpart, ammonia (NH3), provides a higher growth per cycle (GPC), which is approximately 2.3 times higher at a deposition temperature of 300 °C and, also exhibits a low impurity concentration in as-deposited films. Low temperature AlN films deposited at 225 °C with a capping layer had an Al to N composition ratio of 1:1.1, a close to ideal composition ratio, with a low oxygen content (7.5%) while exhibiting a GPC of 0.16 nm/cycle. We suggest that N2H4 as a replacement for NH3 is a good alternative due to its stringent thermal budget.

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