本論文為利用化學氣相傳導法 (CVT) 成長過渡金屬三硫屬化合物 TiS3 及金屬硒代磷酸鹽化合物 AgBiP2Se6，並研究材料之結構、光學與電學特性。藉由 EDS、XPS、TEM 與 XRD 確認成長之材料與預期相符，並得知 TiS3 為單斜晶系而 AgBiP2Se6 為菱方晶系。由拉曼光譜觀察到 TiS3 具有四種 Ag 震動模態，AgBiP2Se6 具有陽離子震盪、Se-P-Se 震動模態及 P-P 拉伸三種震動模態，透過極化拉曼及溫度相依實驗觀察不同角度和溫度下，各震動模態的消長變化，進而探討共面非對稱之特性 (In-Plane Anisotropy)。光學量測中，利用顯微光激螢光光譜、穿透實驗及熱調制光譜可得材料之能隙，TiS3 具有 1.1 eV 直接能隙與 0.9 eV 間接能隙，並觀察到螢光強度會隨著厚度變薄而增強，而 AgBiP2Se6 具有 1.35 eV 能隙躍遷訊號，搭配變溫實驗可發現能量會隨溫度降低而增加，逐漸藍移至 1.47 eV。電學量測中得到 TiS3 電阻率為 0.12 Ω-cm、AgBiP2Se6 電阻率為 0.023 Ω-cm；利用熱探針及霍爾量測可知材料皆為 n 型半導體，濃度分別為 1018 cm-3 及 1019 cm-3。在變溫電阻率實驗中TiS3 呈現半導體行為，AgBiP2Se6 則是金屬行為，最後進行 TiS3 熱電量測顯示其具有高導電度及高 Seebeck 係數。概括上述結果顯示兩材料皆具有很強的光吸收效應及高導電特性，有利於開發相關之光電元件及催化劑。

Structural and opto-electronic characterizations of transition-metal trichalcogenides TiS3 and metal chalcogen-diphosphates AgBiP2Se6 are presented in this study. TiS3 and AgBiP2Se6 single crystals were grown by chemical vapor transport (CVT) using ICl3 as a transport agent. X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy measurements were used to validate the composition of the growth material. Transmission electron microscope and X-ray diffraction verify that TiS3 is crystallized in monoclinic structure while AgBiP2Se6 is rhombohedral structure. Raman spectroscopy reveals that TiS3 has four vibration modes: Agrigid, Aginternal-I, Aginternal-II, and AgS-S. TiS3 exhibits in-plane anisotropy when the direction of the sample is changed. AgBiP2S6 has three vibration modes: cation vibration, Se-P-Se deformation mode, and P-P bond. Polarized Raman and temperature-dependent Raman measurements detect the peak fluctuations and the atomic stretching. Micro-PL, transmittance, and thermoreflectance measurements were done to analyze the energy gap. The direct band gap of TiS3 is 1.1 eV, and its indirect band gap is 0.9 eV. The energy gap of AgBiP2Se6 in 1.35 eV. The temperature-dependent experiment reveals that band gap increases as temperature is decreased, and the value shows blue-shift behavior from 1.35 eV to 1.47 eV. Hall measurements indicate that both materials are n-type semiconductors with high carrier concentration and low resistivity. Compared with the general semiconductor like TiS3, AgBiP2Se6 shows the behavior of the degenerate semiconductor. Thermoelectric measurements for TiS3 reveal a high Seebeck coefficient at 300 K.

[1] J. O. Island, A. J. M. Mendoza, M. Barawi, R. Biele, E. Flores, J. M. Clamagirand, J. R. Ares, C. Sánchez, H. S. J. van der Zant, R. D’Agosta, I. J Ferrer, and A. C. Gomez, "Electronics and optoelectronics of quasi-1D layered transition metal trichalcogenides," 2D Materials, vol. 4, no. 2, p. 022003, 2017.
[2] S. Srivastava and B. Avasthi, "Preparation, structure and properties of transition metal trichalcogenides," Journal of materials science, vol. 27, no. 14, pp. 3693-3705, 1992.
[3] J. O. Island, M. Barawi, R. Biele, A. Almazán, J. M. Clamagirand, J. R. Ares, C. Sánchez, H. S. J. van der Zant, J. V. Álvarez, R. D'Agosta, I. J. Ferrer, and A. C. Gomez, "TiS3 transistors with tailored morphology and electrical properties," Advanced Materials, vol. 27, no. 16, pp. 2595-2601, 2015.
[4] T. V. Vu, O. Y. Khyzhunc, A. A. Lavrentyevd, B. V. Gabreliane, V. I. Sabovf, M. Y. Sabov, M. Y. Filep, A. I. Pogodin, I. E. Barchiy, A. O. Fedorchukh, B. Andriyevsky, and M. Piasecki, "Highly anisotropic layered crystal AgBiP2Se6: Growth, electronic band-structure and optical properties," Materials Chemistry and Physics, vol. 277, p. 125556, 2022.
[5] V. Liubachko, A. Oleaga, A. Salazar, A. Kohutych, K. Glukhov, and Yu. Vysochanskii, "Cation role in the thermal properties of layered materials M1+M3+P2(S, Se)6 (M1+ = Cu, Ag; M3+ = In, Bi)," Physical Review Materials, vol. 3, no. 10, p. 104415, 2019.
[6] B. Xu, H. Xiang, Y. Xia, K. Jiang, X. Wan, J. He, J. Yin, and Z. Liu, "Monolayer AgBiP2Se6: An atomically thin ferroelectric semiconductor with out-plane polarization," Nanoscale, vol. 9, no. 24, pp. 8427-8434, 2017.
[7] H. Schäfer, "Chemical transport reactions," Academic Press, New York, 1964.
[8] D. Hu, G. Xu, L. Xing, X. Yan, J. Wang, J. Zheng, Z. Lu, P. Wang, X. Pan, and L. Jiao, "Two‐dimensional semiconductors grown by chemical vapor transport," Angewandte Chemie International Edition, vol. 56, no. 13, pp. 3611-3615, 2017.
[9] I. J. Ferrer, J. R. Ares, J. M. Clamagir, M. Barawi, and C. Sánchez, "Optical properties of titanium trisulphide (TiS3) thin films," Thin Solid Films, vol. 535, pp. 398-401, 2013.
[10] M. A. Gave, D. Bilc, S. Mahanti, J. D. Breshears, and M. G. Kanatzidis, "On the lamellar compounds CuBiP2Se6, AgBiP2Se6 and AgBiP2S6. Antiferroelectric phase transitions due to cooperative Cu+ and Bi3+ ion motion," Inorganic chemistry, vol. 44, no. 15, pp. 5293-5303, 2005.
[11] H. Seiler, "Secondary electron emission in the scanning electron microscope," Journal of Applied Physics, vol. 54, no. 11, pp. R1-R18, 1983.
[12] C. M. Becchi and M. D'Elia, "Introduction to the basic concepts of modern physics," Springer, New York, 2007.
[13] R. F. Egerton, "Physical principles of electron microscopy," Springer, New York, 2005.
[14] J. F. Watts and J. Wolstenholme, "An introduction to surface analysis by XPS and AES," John Wiley & Sons Inc, New York, 2003.
[15] X. Zhu, R. Birringer, U. Herr, and H. Gleiter, "X-ray diffraction studies of the structure of nanometer-sized crystalline materials," Physical Review B, vol. 35, no. 17, p. 9085, 1987.
[16] C. Kittel, "Introduction to solid state physics," John Wiley & Sons Inc, New York, 1996.
[17] S. N. Magonov and M. H. Whangbo, "Surface Analysis with STM and AFM," VCH, Weinheim, 1996.
[18] P. Graves and D. Gardiner, "Practical raman spectroscopy," Springer, New York, 1989.
[19] S. Perkowitz, "Optical characterization of semiconductors: infrared, Raman, and photoluminescence spectroscopy," Academic Press, San Diego, 1993.
[20] H. W. Verleur, "Determination of optical constants from reflectance or transmittance measurements on bulk crystals or thin films," Journal of the Optical Society of America, vol. 58, no. 10, pp. 1356-1364, 1968.
[21] B. Seraphin, R. Hess, and N. Bottka, "Field Effect of the Reflectivity in Germanium," Journal of Applied Physics, vol. 36, no. 7, pp. 2242-2250, 1965.
[22] F. H. Pollak and H. Shen, "Modulation spectroscopy of semiconductors: bulk/thin film, microstructures, surfaces/interfaces and devices," Materials Science and Engineering R: Reports, vol. 10, no. 7-8, pp. xv-374, 1993.
[23] C. H. Ho, H. W. Lee, and Z. H. Cheng, "Practical thermoreflectance design for optical characterization of layer semiconductors," Journal of Review of Scientific Instruments, vol. 75, no. 4, pp. 1098-1102, 2004.
[24] A. Axelevitch and G. Golan, "Hot-probe method for evaluation of majority charged carriers concentration in semiconductor thin films," Facta universitatis-series Electronics and Energetics, vol. 26, no. 3, pp. 187-195, 2013.
[25] O. Philips’Gloeilampenfabrieken, "A method of measuring specific resistivity and Hall effect of discs of arbitrary shape," Philips Research Report, vol. 13, no. 1, pp. 1-9, 1958.
[26] D. K. Schroder, "Semiconductor material and device characterization," John Wiley & Sons Inc, New York, 1990.
[27] K. Uchida, S. Takahashi, K. Harii, J. Ieda, W. Koshibae, K. Ando, S. Maekawa, and E. Saitoh, "Observation of the spin Seebeck effect," Journal of Nature, vol. 455, no. 7214, pp. 778-781, 2008.
[28] T. C. Harman, J. H. Cahn, and M. J. Logan, "Measurement of thermal conductivity by utilization of the Peltier effect," Journal of Applied Physics, vol. 30, no. 9, pp. 1351-1359, 1959.
[29] W. H. Chen, C. Y. Liao, and C. I. Hung, "A numerical study on the performance of miniature thermoelectric cooler affected by Thomson effect," Journal of Applied Energy, vol. 89, no. 1, pp. 464-473, 2012.
[30] 倪祥圃, "熱電優值 ZT 量測方法之研究與實作," 碩士, 機械工程學研究所, 國立臺灣大學, 台北市, 2016.
[31] M. E. Fleet, S. L. Harmer, X. Liu, and H. W. Nesbitt, "Polarized X-ray absorption spectroscopy and XPS of TiS3: S K-and Ti L-edge XANES and S and Ti 2p XPS," Surface science, vol. 584, no. 2-3, pp. 133-145, 2005.
[32] K. Endo, H. Ihara, K. Watanabe, and S. I. Gonda, "XPS study of one-dimensional compounds: TiS3," Journal of Solid State Chemistry, vol. 44, no. 2, pp. 268-272, 1982.
[33] J. F. Moulder, W. F. Stickle, P. E. Sobol, and K. D. Bomben, "Handbook of X-ray photoelectron spectroscopy," Perkin-Elmer Corporation, Minnesota, 1992.
[34] A. Lipatov, M. J. Loes, H. Lu, J. Dai, P. Patoka, N. S. Vorobeva, D. S. Muratov, G. Ulrich, B. Kästner, A. Hoehl, G. Ulm, X. C. Zeng, E. Rühl, A. Gruverman, P. A. Dowben, and A. Sinitskii, "Quasi-1D TiS3 nanoribbons: mechanical exfoliation and thickness-dependent Raman spectroscopy," ACS Nano, vol. 12, no. 12, pp. 12713-12720, 2018.
[35] N. Tripathi, V. Pavelyev, P. Sharma, S. Kumar, A. Rymzhina and P. Mishra, "Review of titanium trisulfide (TiS3): A novel material for next generation electronic and optical devices," Materials Science in Semiconductor Processing, vol. 127, p. 105699, 2021.
[36] W. Kong , C. Bacaksiz, B. Chen, K. Wu, M. Blei, X. Fan, Y. Shen, H. Sahin, D. Wright, D. S. Narang, and S. Tongay, "Angle resolved vibrational properties of anisotropic transition metal trichalcogenide nanosheets," Journal of Nanoscale, vol. 9, no. 12, pp. 4175-4182, 2017.
[37] Y. P. Varshni, "Temperature dependence of the energy gap in semiconductors," physica, vol. 34, no. 1, pp. 149-154, 1967.
[38] L. M. Beley, O. A. Mykajlo, V. O. Stephanovych, and I. P. Studenjak, "Dipole glassy state evidence for CuInP2(SexS1-x)6 ferrielectric mixed crystals from Raman scattering and optical absorption data," Ukrainian Journal of Physical Optics, vol. 8, pp. 13-24, 2007.
[39] X. Wang, J. Wang, J. Wang, B. Wei, and Z. Wang, "Atomic structure and electronic property of two-dimensional ferroelectric CuInP2Se6," Ceramics International, vol. 46, no. 6, pp. 7014-7018, 2020.
[40] C. H. Ho, S. F. Hu, and H. W. Chang, "Thermoreflectance characterization of the band-edge excitons observed in multilayered CuInP2S6," FlatChem, vol. 29, p. 100290, 2021.