Evolution transients were measured in hydrogenated amorphous material which had been prepared by the Si implantation of crystalline Si, followed by H implantation. The evolution curves were found to be similar for various H concentrations, but were associated with entirely different atomic and nano-scale structures; as revealed by small-angle X-ray scattering and infra-red absorption data. The results were explained in terms of H diffusion-controlled effusion, with a limited density of available sites, in the amorphous material, for occupation by H. Diffusion through highly disordered material with a low H content was found to be governed by an activation energy of 2.26eV.

S.Acco, W.Beyer, E.E.Van Faassen, W.F.Van der Weg: Journal of Applied Physics, 1997, 82[6], 2862-8

 

Table 174

Diffusivity of D and H in Si

 

Diffusant

T (K)

D (cm2/s)

D

270

3.7 x 10-12

D

265

2.2 x 10-12

D

260

1.6 x 10-12

D

255

1.2 x 10-12

D

250

6.6 x 10-13

D

245

4.7 x 10-13

D

240

1.9 x 10-13

D

235

1.8 x 10-13

D

230

8.2 x 10-14

D

225

5.4 x 10-14

H

270

7.6 x 10-12

H

265

5.7 x 10-12

H

260

2.7 x 10-12

H

255

1.9 x 10-12

H

245

6.0 x 10-13

H

240

3.7 x 10-13

H

235

2.8 x 10-13

H

230

1.2 x 10-13

H

220

4.0 x 10-14