"STUDY OF STRUCTRE AND PROPERTY OF MAGNETIC FILMS MADE WITH M.B.E."

1998 Fiscal Year Final Research Report Summary

• Project/Area Number: 09650765
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Structural/Functional materials
• Research Institution: KYUSHU UNIVERSITY
• Principal Investigator: MASUDA Masataka KYUSHU UNIVERSITY,FACULTY OF ENGINEERING,ASSOCIATE PROFESSOR, 工学研究科, 助教授 (40165725)
• Co-Investigator(Kenkyū-buntansha): JYOKO Yukimi KYUSHU UNIVERSITY,FACULTY OF ENGINEERING,ASSISTANT, 工学研究科, 助手 (40211974)
• Project Period (FY): 1997 – 1998
• Keywords: MBE METHOD / ARTIFICIAL LATICE FILMS / Pt-Co MULTI-LAYER FILMS / MAGNETIC DOMAIN STRUCTURE / M.F.M

Research Abstract

I made artificial lattice films of Pt/Co with the MBE.I valued the effect of the growth speed and the substrate temperature on the film structure by the "in situ" RHEED analysis, and I decided a suitable film formation condition. For the formation films on silicon (Ill) substrate, it was valued as a suitable condition to make Pt layer of 20 nm thickness, of 473K temperature as a buffer layer. I evaluated the boundary strain and the consistency of films with the precise measurements of AFM on surface structure of films. By the thin film X-ray diffraction, I evaluated fine structure of films and I attempted, to quantify the stacking property of films as an artificial lattice. With XPS analysis, which is connected with ultra high vacuum tunnel to MBE chamber, I made sure the composition modulation of nm order period that is formed normal directions to the film. The result of VSM measurement showed that the period of artificial lattice and formation condition of films affect the magnetic characteristic. By observation of magnetic domain structure with MFM, I found that domain size decreases with the increasing of Co layer thickness. We explained this phenomenon with the evaluation of magnetic energy as sum of static magnetic energy and magnetic wall energy. We calculated static magnetic potential distribution with BEM for the magnetic domains with magnetic wall of 90 degree and 45 degree. We compared the result of MFM with the calculated value arid discussed magnetic domain structure of artificial lattice films.
We improved the Hall magnetic measurement device to measure giant magnetic resistivity in 5kOe magnetic field. We confirmed that boundary structure of films affects magnetic characteristic. We discussed the magnetic characteristic of the granular structure films prepared with sputtering device. We evaluated the magnetic characteristic and X-ray diffraction profile under the alternation of boundary structure by the annealing.