| 학회 | 한국재료학회 |
| 학술대회 | 2016년 가을 (11/16 ~ 11/18, 경주 현대호텔) |
| 권호 | 22권 2호 |
| 발표분야 | G. 나노/박막 재료 분과 |
| 제목 | Optimization of tin monosulfide thin film by atomic layer deposition |
| 초록 | According to the rise of renewable energy technology, thin film solar cell has been researched with copper indium gallium selenide (CIGS), cadmium telluride (CdTe) as the alternative of silicon based solar cell. They have an outstanding conversion efficiency due to high absorption coefficient and suitable band gap for solar cell. However, high cost of indium, tellurium, and gallium is a problem, due to their reserves or refinement process. Furthermore, cadmium is a very toxic metal to be grouped 1 carcinogen classified by the International Agency for Research on Cancer (IARC). Hence, new material is required to substitute CIGS and CdTe. Among recent studied materials, tin monosulfide (SnS) is a promising material as thin film solar cell absorber. SnS is non-toxic and has low cost due to its abundance. Additionally, it has proper optical properties for solar cells, direct band gap of 1.4 eV and high absorption coefficient above 104 cm-1. But high crystallinity (large grain size) and large area uniformity should be achieved to apply as solar cell absorber. In this study, SnS thin films were deposited on Si/SiO2 (285nm oxidized) substrate with tetrakis(dimethylamino)tin (Sn[N(CH3)2]4, TDMASn) and hydrogen sulfide (H2S) by atomic layer depositon (ALD). To optimize SnS ALD process for high crystallinity and uniform film, we changed process pressure, dosing time and purge time at 160℃. TDMASn and H2S injection time ratio were fixed to 1:3. Then, we synthesized SnS film at 160, 170, 180, 190℃ with the selected process condition. Grain size, crystallinity and uniformity were analyzed with X-ray diffractometer (XRD) and atomic force microscopy (AFM). Film thickness, structure and SAD (selected area diffraction) pattern were verified by transmission electron microscope (TEM). The chemical bonding state, compositions were characterized, using X-ray photoelectron spectroscopy (XPS). Optical properties such as absorption coefficient, optical band offset and minority carrier lifetime were measured by ultraviolet/visible/near- infrared spectrophotometer, ultraviolet photoelectron spectroscopy (UPS) and time-resolved photoluminescence (TRPL) respectively. |
| 저자 | 최형수, 신석윤, 박주현, 함기열, 이주현, 이승진, 전형탁 |
| 소속 | 한양대 |
| 키워드 | solar cell; crystallinity; uniformity; tetrakis(dimethylamino)tin (TDMASn); Atomic Layer Deposition (ALD) |
