http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Hot wall epitaxy방법에 의한 AgInS<sub>2</sub> 박막의 성장과 광전류 특성
김혜숙,홍광준,정준우,방진주,김소형,정태수,박진성,Kim, H.S.,Hong, K.J.,Jeong, J.W.,Bang, J.J.,Kim, S.H.,Jeong, T.S.,Park, J.S. 한국재료학회 2002 한국재료학회지 Vol.12 No.7
A silver indium sulfide ($AgInS_2$) epilayer was grown by the hot wall epitaxy method, which has not been reported in the literature. The grown $AgInS_2$ epilayer has found to be a chalcopyrite structure and evaluated to be high quality crystal. From the photocurrent measurement in the temperature range from 30 K to 300 K, the two peaks of A and B were only observed, whereas the three peaks of A, B, and C were seen in the PC spectrum of 10 K. These peaks are ascribed to the band-to-band transition. The valence band splitting of $AgInS_2$ was investigated by means of the photocurrent measurement. The crystal field splitting, $\Delta_{cr}$ , and the spin orbit splitting, $\Delta_{so}$ , have been obtained to be 0.150 eV and 0.009 eV at 10 K, respectively. And, the energy band gap at room temperature has been determined to be 1.868 eV. Also, the temperature dependence of the energy band gap, $E_{g}$(T), was determined.d.
HWE(Hot Wall Epitaxy)에 의한 CuGaSe₂/GaAs epilayer 성장과 광전기적 특성
홍광준,정준우,백형원,정경아,방진주,진윤미,김소형 조선대학교 기초과학연구소 2001 自然科學硏究 Vol.24 No.-
수평 전기로에서 CuGaSe₂ 다결정을 합성하여 HWE(Hot Wall Epitaxy) 방법으로 CuGaSe₂/GaAs epilayer를 반절연성 GaAs(100)기판 위에 성장하였다. CuGaSe₂/GaAs epilayer는 증발원의 온도를 610℃, 기판의 온도를 450℃로 하였다. CuGaSe₂/GaAs epilayer의 결정성의 조사에서 20K에서 광발광(photoluminescence) 스펙트럼이 672.6nm(1.8432eV)에서 엑시톤 방출 스펙트럼이 가장 강하게 나타났으며, 이중결정 X-선 요동곡선(DCRC)의 반폭치(FWHM)도 138 arcsec로 가장 작아 최적 성장 조건임을 알 수 있었다. Hall 효과는 van der Pauw 방법에 의해 측정되었으며, 온도에 의존하는 운반자 농도와 이동도는 293K에서 각각 4.87×10^(23) electron/m³, 1.29×10² m²/v-s 였다. CuGaSe₂/GaAs epilayer의 광전류 단파장대 봉우리들로부터 20K에서 측정된 ΔCr(Crystal field splitting)은 약 0.09 eV ΔSo(spin orbit coupling)는 0.2498 eV였다. 20K의 광발광 측정으로부터 고품질의 결정에서 볼 수 있는 자유 엑시톤 (free exciton)과 매우 강한 세기의 중성 받개(acceptor) 구속 엑시톤 (bound exciton)등의 피크가 관찰되었다. 이때 받개 구속 엑시톤 (bound exciton)의 반치폭과 결합에너지는 각각 8meV와 93.2meV 였다. 또한 Haynes rule에 의해 구한 불순물의 활성화 에너지는 466meV였다. The stochiometric mixture of evaporating materials for the CuGaSe₂/GaAs epilayer was prepared from horizontal furnace. Using extrapolation method of X-ray diffraction patterns for the polycrystal CuGaSe₂, it was found tetragonal structure whose lattice constant a_(0) and c_(0) were 5.615 Å and 11.025 Å, respectively. To obtain the CuGaSe₂/GaAs epilayer, CuGaSe₂ mixed crystal was deposited on throughly etched GaAs(100) by the Hot Wall Epitaxy(HWE) system. The source and substrate temperature were 610 ℃ and 450 ℃ respectively. The crystalline structure of CuGaSe₂/GaAs epilayer was investigated by the double crystal X-ray diffraction(DCXD). Hall effect on this sample was measured by the method of van der pauw and studied on carrier density and mobility depending on temperature. From Hall data, the mobility was likely to be decreased by pizoelectric scattering in the temperature range 30 K to 150 K and by polar optical scattering in the temperature range 150 K to 293 K. From the photocurrent spectra by illumination of polarized light of the CuGaSe₂/GaAs epilaye. We have found that values of spin orbit coupling ΔSo and crystal field splitting ΔCr was 0.0900 eV and 0.2498 eV, respectively. From the photoluminescence measurement of CuGaSe₂/GaAs epilayer, we observed free excition(Ex) observable only in high quality crystal and neutral acceptor-bound exciton (A^(0); X) having very strong peak intensity. And, the full width at half maximum and binding energy of neutral donor bound excition were 8 meV and 93.2 meV, respectively. By Haynes rule, an activation energy of impurity was 466 meV.