| Project/Area Number |
05045034
|
|---|
| Research Category |
Grant-in-Aid for international Scientific Research
|
| Allocation Type | Single-year Grants |
|---|
| Section | University-to-University Cooperative Research |
|---|
| Research Institution | Shibaura Institute of Technology |
|---|
Principal Investigator |
NAGATOMO Takao Shibaura Inst.of Tech., Professor, 工学部, 教授 (70052868)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
魏 光普 上海大学, 材料科学系, 教授
張 志林 上海大学, 材料科学系, 教授
OMOTO Osamu Shibaura Inst.of Tech., Professor, 工学部, 教授 (60052693)
WEI Gaung-pu Shanghai University, Professor
ZHANG Zhi-lin Shanghai University, Professor
米井 健治 芝浦工業大学, 工学部, 教授 (50052816)
|
|---|
| Project Period (FY) |
1993 – 1994
|
| Project Status |
Completed (Fiscal Year 1994)
|
| Budget Amount *help |
¥4,000,000 (Direct Cost: ¥4,000,000)
Fiscal Year 1994: ¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1993: ¥2,000,000 (Direct Cost: ¥2,000,000)
|
|---|
| Keywords | Tin sulfide / Tin disulfide / Vacuum-Evaporation / Valency Control / Characterization / Heterojunction / Photovoltaic Effect / Thin Film Solar Cell / SnS_2 pnヘテロ接合19GA01:棚村浩匡、野口英智、野口純司、長友隆男、大本修 / 硫化錫 / ヘテロ接合 |
|---|
| Research Abstract |
Tin sulfide (SnS) is one of the promising materials for low-cost thin film solar cell, because of a bandgap of 1.3-1.4eV and the absorption coefficient larger than 10^4cm^<-1>. In this study, we have investigated the physical properties of vacuum-evaporated SnS films and the photovoltaic properties n-CdS/p-SnS and n-SnS_2/p-SnS heterojunctions.
Vacuum-deposited SnS films are always p-type conduction with a resistivity of 13-20OMEGAcm, carrier density of 6.3*10^<14>-1.2*10^<15>cm^<-3>, and a Hall mobility of 400-500cm^2/Vs. The activation energy for conduction of the SnS films was about 0.28-0.34eV.The resistivity of SnS films became about two order of magnitude larger than that of as-grown films by the doping of antimony metal. We cannot get an n-type SnS film in the present stage.
The n-CdS/p-SnS heterojunctions were made by depositing n-CdS,p-SnS and Ag ohmic electrode on the transparent electrode ITO films by turns. The barrier height phi_B was estimated to be 0.56eV from the saturation current, assuming Richardson constant of a free electron. The 1/C^2-V curve is roughly straight line, the voltage intercept is 0.49V.The heterojunction behaves as a metal/semiconductor Schottky barrier, in which the CdS layr plays the role of a metal. From the analysis of the slope of 1/C^2-V plots measured at 1MHz, the width of the depletion layr at zero bias was 3.01*10^<-5>cm. The photovoltaic properties of a short-circuit current of 7mA/cm^2, an open-circuit voltage of 0.1V,and a fill factor of 0.42 for n-CdS/p-SnS heterojunction were obtained under the illumination of 100 mW/cm^2.
From the analysis of Ag/n-SnS_2 and Al/p-SnS Schottky diodes, the electron affinities of n-SnS_2 and p-SnS films were 4.67eV and 3.72eV,respectively. Accordingly, SnS_2 film is not suitable for the window material of p-SnS film.
|
