JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS, vol. 34, no. 4A, page. 1916 - 1921, 1995-04
JOURNAL OF APPLIED PHYSICS, vol. 78, no. 9, page. 5604 - 5608, 1995-11-01
APPLIED SURFACE SCIENCE, vol. 78, no. 3, page. 285 - 292, 1994-07