Experimental evidence for the transient enhanced diffusion of B in ion-implanted samples was presented. The implanted B diffused several μm into the samples when they were annealed at 1600 and 1700C for 600s, but the in-diffused tails remained unaffected when the annealing time was increased to 0.5h at the same temperatures. The lower limit on the effective B diffusivity at 1600C was estimated to be 7 x 10-12cm2/s (table 9). This value was 160 times higher than published equilibrium B diffusivities.

Transient Enhanced Diffusion of Implanted Boron in 4H-Silicon Carbide M.S.Janson, M.K.Linnarsson, A.Hallén, B.G.Svensson, N.Nordell, H.Bleichner: Applied Physics Letters, 2000, 76[11], 1434-6

 

 

Table 9

Effective Diffusivities of B in SiC

 

Sample

Temperature (C)

D (cm2/s)

implanted

1600

6.7 x 10-12

implanted

1700

1.3 x 10-11

implanted

2050

2.5 x 10-11

buried layer

1700

2.0 x 10-13