Hostname: page-component-7b7567c8c-7pwfn Total loading time: 0 Render date: 2026-11-15T19:59:21.172Z Has data issue: false hasContentIssue false

Deposition of Gan Films Using Seeded Supersonic Jets

Published online by Cambridge University Press:  21 February 2011

H. Henry Lamb
Affiliation:
Department of Chemical Engineering, North Carolina State University, Raleigh, NC 27695-7905
Ken K. Lai
Affiliation:
Department of Chemical Engineering, North Carolina State University, Raleigh, NC 27695-7905
Victor Torres
Affiliation:
Department of Materials Science and Engineering, North Carolina State University, Raleigh, NC 27695-7907
Robert F. Davis
Affiliation:
Department of Materials Science and Engineering, North Carolina State University, Raleigh, NC 27695-7907
Get access

Abstract

GaN films were deposited on sapphire (0001) from triethylgallium (TEG) and NH3 seeded in separate He free jets. as the dissociative chemisorption of NH3 is expected to be rate-limiting in GaN growth, the NH3/He nozzle temperature was varied to control the incident kinetic energy of the NH3 molecules. Using an NH3/TEG flow ratio of 205 and an NH3/He nozzle temperature of 400°C, stoichiometric films were deposited at substrate temperatures ≥530°C. Scanning electron microscopy revealed that films deposited at 580°C are polycrystalline α-GaN with randomly oriented 0.5-μm grains. Films with a closely similar morphology are deposited by using an NH3/He nozzle temperature of 90°C. IN contrast, films deposited at 580°C using an NH3/He nozzle temperature of 510°C consist of whiskers (aspect ratio = c A. 4) which exhibit a-GaN (0001)/sapphire (0001) heteroepitaxy, as evidenced by X-ray diffraction and reflection high-energy electron diffraction.

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable