2006 Fiscal Year Final Research Report Summary
Microstructure characterization of semiconducting iron disilicide thin films by using the HARECXS and the CBED methods
| Project/Area Number |
16360315
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Physical properties of metals
|
|---|
| Research Institution | KYUSHU UNIVERCITY |
|---|
Principal Investigator |
ITAKURA Masaru Kyushu University, Faculty of Engineering Sciences, Associate Professor, 大学院総合理工学研究院, 助教授 (20203078)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
HATA Satoshi Kyushu University, Faculty of Engineering Sciences, Associate Assistant, 大学院総合理工学研究院, 助手 (60264107)
KUWANO Noriyuki Kyushu University, Art, Science and Technology Center for Cooperative Research, Professor, 産学連携センター, 教授 (50038022)
OKUYAMA Tetsuya Kurume National College of Technology, Professor, 助教授 (40270368)
|
|---|
| Project Period (FY) |
2004 – 2006
|
| Keywords | iron disilicide / thin films / epitaxial growth / transmission electron microscopy / ALCHEMI / CBED / crystallographic orientation / silicon substrate |
|---|
| Research Abstract |
In this study, epitaxial β-FeSi_2 films were prepared by sputtering on the flat and the patterned Si(001) substrates under various substrate temperatures (T_s) with deposition rates of Fe (V_<Fe>), and the microstructures of these films were characterized by transmission electron microscopy (TEM). The following results were obtained.
(1)In the film deposited on the flat Si(001) substrate, precipitates of flat-bottom shaped β-FeSi_2 and those of round-bottom shaped α-FeSi2 are formed at T_s=500℃ and V_<Fe>=0.02 nm/s. The β-FeSi_2 adopts the epitaxy to (001)_<Si>, plane, while α-FeSi_2 selects the epitaxy to {111}_<Si>, planes inside the Si matrix. At T_s=350℃ and V_<Fe>=0.01 nm/s, a continuous β-FeSi_2 layer are formed epitaxially on the Si(001) substrate without forming α-FeSi_2. The lower temperature and the higher Fe-concentration suppress the formation of a-FeSi_2 and promote the formation of β-FeSi_2.
(2)In the film deposited on the patterned Si(001) substrate, both β-and α-FeSi_2 precipitates are formed in the top-hills and the valleys of the patterned substrate, while only α-FeSi_2 precipitates are formed in the sidewalls. Not only the growth conditions but also geometric situations affect strongly the epitaxial growth of FeSi_2 precipitates.
(3)In the film deposited on Cu-mediated Si(001) substrate, non-radiative recombination centers in the β-FeSi_2 grains and the hetero-interface are improved, and then PL intensity from the β-FeSi_2 grains can be increased significantly.
(4)ALCHEMI (atom location by channeling enhanced microanalysis) method of electron diffraction was employed to study the atomic configuration of the β-FeSi_2 film grown on Cu-mediated Si(001) substrate. In the β-FeSi_2 film, Cu atoms tend to occupy the Fe-site.
(5)Clear CBED (convergent beam electron diffraction) patterns from the β-FeSi_2 grain and the Si substrate were measured successfully, in order to estimate the lattice strain near the hetero-interface.
|
