Investigation of micropores in amorphous hydrogenated carbon by a pulsed positron beam
The positron lifetime (PLT) in a thin film of amorphous hydrogenated carbon (a-C:H) was studied by a pulsed positron beam. For the first time the PLT was measured in a layer which is as thin as 100 nm. PLTs of 400(5) ps for the surface state and 348(3) ps in the volume of the film were obtained. The diffusion length of the positrons was measured to be only 4(1) nm. From these results, it was concluded that in the specimen investigated at least 3% of the total volume is occupied by micropores about 0.5 nm in diameter, which may make possible the diffusion of molecular hydrogen in a-C:H.
Bibliographic Reference: Article: Physical Review Letters, Volume 60 (1988), No. 15, pp. 1550-1553
Record Number: 198910475 / Last updated on: 1994-12-01
Original language: en
Available languages: en