NiO: Co, Mg Diffusion

The migration of Co and Mg in monocrystals was measured, at various temperatures and partial pressures, by depositing a thin film of the diffusant, by annealing, and by using secondary ion mass spectrometry or X-ray spectrometry to monitor the diffusion profiles. It was found that the results (tables 111 and 112) could be described by the expressions:

Mg: D (cm2/s) = 1.45 x 10-2PO2 (atm)0.172 exp[-2.58(eV)/kT]

Co: D (cm2/s) = 5.15 x 10-2PO2 (atm)0.175 exp[-2.54(eV)/kT]

By further analyzing the data, some insight into the impurity/vacancy interactions was obtained. This suggested that Co and Mg interacted quite strongly with VNi" during exchange jumps, but hardly interacted at all when they were in stable positions.

H.Boussetta, N.Tabet, C.Monty: Journal de Physique III, 1992, 2[10], 1845-71

Table 111

Diffusion of Mg in NiO

Temperature (C)	PO2 (atm)	D (cm2/s)
1016	0.00003	8.6 x 10-13
1100	0.21	3.8 x 10-12
1103	0.00001	1.35 x 10-12
1165	0.00006	3.05 x 10-12
1200	0.21	1.75 x 10-11
1210	0.00005	5.36 x 10-12
1210	0.011	1.82 x 10-11
1210	0.0025	1.5 x 10-11
1210	0.00058	1.1 x 10-11
1245	0.00018	1.0 x 10-11
1245	0.00005	7.54 x 10-12
1245	0.00003	6.86 x 10-12
1245	0.000002	6.76 x 10-12
1296	0.00007	1.85 x 10-11
1300	0.21	6.1 x 10-11
1305	0.00005	2.07 x 10-11
1400	0.21	1.6 x 10-10
1400	0.00016	5.53 x 10-11
1485	0.00015	1.29 x 10-10
1500	0.21	3.8 x 10-10
1600	0.21	1.1 x 10-9
1700	0.21	2.5 x 10-9

Table 112

Diffusion of Co in NiO

Temperature (C)	PO2 (atm)	D (cm2/s)
1100	0.21	1.94 x 10-11
1100	0.0005	1.39 x 10-11
1125	0.00019	1.6 x 10-11
1170	0.21	5.4 x 10-11
1180	0.00014	2.3 x 10-11
1200	0.21	7.94 x 10-11
1245	0.011	9.8 x 10-11
1245	0.0025	6.4 x 10-11
1245	0.00058	5.36 x 10-11
1245	0.00018	4.8 x 10-11
1245	0.00003	3.6 x 10-11
1245	0.000001	2.56 x 10-11
1245	0.0000002	2.28 x 10-11
1300	0.21	3 x 10-10
1315	0.00008	9.31 x 10-11
1394	0.0005	3.3 x 10-10
1400	0.21	8.13 x 10-10
1500	0.21	2.26 x 10-9
1510	0.0006	1.17 x 10-9
1600	0.21	5.46 x 10-9
1700	0.21	1.29 x 10-8