2011 journal article

Spectroscopic measurements of the surface stoichiometry of chemical vapor deposited GaN

APPLIED PHYSICS LETTERS, 98(8).

By: H. Craft n, A. Rice n, R. Collazo n, Z. Sitar n & J. Maria n

co-author countries: United States of America 🇺🇸
Source: Web Of Science
Added: August 6, 2018

We report on the surface stoichiometry of Ga-polar GaN films grown by metalorganic chemical vapor deposition as studied by x-ray photoelectron spectroscopy. GaN film surfaces are found to be Ga-rich, with Ga:N ratios ranging from 1.3:1 to 3.2:1. In vacuo ion-beam sputter/annealing studies show that these treatments drive the apparent Ga:N surface composition farther from unity, either through a decrease in surface contamination, oxidation of the surface, or both. Simple annealing experiments decrease the Ga:N ratio. The measured GaN ratio is correlated with the GaN growth time, suggesting that residual Ga precursor after growth interacts with the GaN surface as it cools.