Lithium ions with dosages of 2.6 x 1012, 2.6 x 1013, 2.6 x 1014 and 2.6 x 1015/cm2 were implanted into a GaN thin film grown on sapphire substrates. The diffusion behavior of these implanted Li ions in GaN thin film at different temperature anneals was studied using secondary ion mass spectrometry. In general, the diffusion profiles showed relatively little movement of Li in the GaN thin film at up to 700C. At <500C), up-hill diffusion dominated the Li profiles and, at >800C, out-diffusion dominated the Li profiles.

Diffusion Behavior of Implanted Li Ions in GaN Thin Films Studied by Secondary Ion Mass Spectrometry. F.Salman, L.Chow, B.Chai, F.A.Stevie: Materials Science in Semiconductor Processing, 2006, 9[1-3], 375-9

Figure 1

Diffusivity of Sn in Epitaxial GaN

(open circles: microscopic – no AlN, open squares: macroscopic – no AlN

filled circles: microscopic – AlN, filled squares: macroscopic – AlN)