研究生: |
饒峻宇 Jao, Chun-Yu |
---|---|
論文名稱: |
鈷-60加馬射線對稠五苯薄膜的各向異性結構與電子特性之影響 The effects of Co60 gamma-ray on the structure and electronic properties of pentacene thin-film anisotropically |
指導教授: |
李志浩
Lee, Chih-Hao |
口試委員: |
楊耀文
Yang, Yaw-Wen 王嘉興 Wang, Chia-Hsin |
學位類別: |
碩士 Master |
系所名稱: |
原子科學院 - 核子工程與科學研究所 Nuclear Engineering and Science |
論文出版年: | 2020 |
畢業學年度: | 108 |
語文別: | 中文 |
論文頁數: | 74 |
中文關鍵詞: | 輻射損傷 、稠五苯 、X射線 、X射線吸收光譜 、電子特性 |
外文關鍵詞: | Radiation damage, Pentacene, X-ray, X-ray absorption spectroscopy, Electronic properties |
相關次數: | 點閱:3 下載:0 |
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本次研究使用熱蒸鍍將稠五苯沉積於熱生長300 nm的二氧化矽之重摻雜(p-type)矽基板上,並暴露於60Co加馬射線下接受輻射照射,接著探討稠五苯薄膜受輻射照射後在In-Plane(面內)與Plane Normal(面外)各向異性上的原子結構、電子結構、電阻率以及載子遷移率等變化。
利用國家同步輻射中心(NSRRC)的光束線來分析樣品;由X-ray繞射觀察到既使在3000 Gy輻射照射下的稠五苯薄膜與未受輻射照射的樣品相比其積分強度下降仍不超過10%,可能暗示著在結晶性、分子排序程度等結構方面擁有著不錯的輻射抗性;接著使用X-ray近吸收邊光譜學分析其電子結構,觀察到經過輻射照射後電子軌域的未佔據態提升,可能是經過輻射暴露後於稠五苯薄膜中產生了更多的能態缺陷來幫助載子傳輸擁有更多能量與空間的位置來躍遷使得導電性增加;亦或是在輻射暴露期間於稠五苯內部產生了許多的自由基或離子而導致載子濃度增加。
在量測稠五苯薄膜電性時,觀察到輻射照射後的面內電阻下降而面外電阻變化極小,因此利用霍爾效應確認薄膜載子濃度的改變,發現輻射照射後的載子濃度逐漸上升使得薄膜的導電度增加,且各向異性上的載子遷移率隨劑量增加而下降,可能是輻射照射後分子排序輕微變差所導致的。另外,藉著後退火處理嘗試恢復薄膜的初始特性,並利用XRD觀察到在較低劑量400 Gy的條件下其繞射峰強度恢復至原本的90%,但在3000 Gy的高劑量下並無改變,此結果可能是由於高劑量下所造成的永久性輻射損傷而導致的;而在電阻率方面僅能恢復至原本的30%,無法完全恢復至初始電阻率。
經過這次的實驗與分析,由於輻射照射後稠五苯薄膜電子特性的改變顯著,或許可以使稠五苯應用在高輻射區域中作為感測器,但後退火處理並無法讓電性完全的恢復,故作為可重複使用的輻射偵檢器,必須有更深入的討論與研究。
Pentacene thin films was prepared by thermal evaporation technique on a heavily p-type doped silicon substrate containing thermally grown 300 nm SiO2. And the sample was irradiated by using Co60 gamma source. The variation of atomic structure, electronic structure, resistivity and carrier mobility of pentacene film before and after irradiation were studied.
X-ray diffraction results showed that even after radiation to 3000 Gy, the degradation of integrated intensity of pentacene is less than 10% when compared to pristine sample, suggesting that the structure of pentacene remains robust. The electronic structure of pentacene films were analyzed by using near edge x-ray absorption spectroscopy. We noticed that in case of irradiated samples density of the unoccupied state increased might be due to some energy states created during irradiation to help carrier transport or increase in carrier concentration might be due to ions and free radicals formed during irradiation.
Electrical measurement results revealed a decrease in in-plane resistivity and a negligible change for plane-normal resistivity after irradiation. So we used Hall Effect measurement to determine carrier concentration. This result is consistent with XAS data in which an increase in carrier concentration after irradiation was also revealed. Mobility decrease might be due to the structural disorder present after irradiation. In addition, we observed from post-annealing treatment that in case of low dose, the XRD intensity gets recovered around 90% , whereas in case of high dose samples only slight change was observed which could be due to permanent defects created in the sample. Whereas the resistivity after post annealing treatment gets recovered by about 30%. Overall, the experimental results point to a possible use of pentacene for radiation sensor applications in the future.
1. Tsumura, A., H. Koezuka, and T. Ando, "Macromolecular electronic device: Field‐effect transistor with a polythiophene thin film". Applied Physics Letters, 1986. 49(18): p. 1210-1212.
2. Cantatore, E., et al.," A 13.56-MHz RFID System Based on Organic Transponders". IEEE Journal of Solid-State Circuits, 2007. 42(1): p. 84-92.
3. Baude, P.F., et al., "Pentacene-based radio-frequency identification circuitry". Applied Physics Letters, 2003. 82(22): p. 3964-3966.
4. M. G. Kane, I.G.H., J. Campi, M. S. Hammond, B. Greening, C. D., J.A.N. Sheraw, D. J. Gundlach, J. R. Huang, C. C. Kuo, L. Jia, T. N., and J.L.W. Jackson, J. Francl, "AMLCDs using Organic Thin-Film Transistors on Polyester Substrates".SID Symposium Digest of Technical Papers, 2001.
5. Mabeck, J.T. and G.G. Malliaras, "Chemical and biological sensors based on organic thin-film transistors". Anal Bioanal Chem, 2006. 384(2): p. 343-53.
6. B. Nickel, et al.,"Dislocation arrangements in pentacene thin films". Physical Review B, 2004. 70(12).
7. Veaceslav Coropceanu, J.r.m.C., Demetrio A. da Silva Filho, Yoann Olivier, Robert Silbey, and Jean-Luc Bre´das, "Charge Transport in Organic Semiconductors''. American Chemical Society, 2007.
8. Malenfant, C.D.D.a.P.R.L., ''Organic Thin Film Transistors for Large Area Electronics''. Adv. Mater, 2002.
9. 維基百科Polythiophene, https://upload.wikimedia.org/wikipedia/commons/0/03/Polythiophene_repeat_unit.png.
10. 維基百科Polyacetylene, https://zh.wikipedia.org/wiki/%E8%81%9A%E4%B9%99%E7%82%94#/media/File:Trans-Polyacetylene.svg.
11. Shirakawa, H., ''The Discovery of Polyacetylene Film: The Dawning of an Era of Conducting Polymers (Nobel Lecture)''. Angew. Chem. Int. Ed, 2001.
12. 維基百科Rubrene, https://en.wikipedia.org/wiki/Rubrene#/media/File:Rubrene.svg.
13. 維基百科C60, https://zh.wikipedia.org/wiki/%E5%B7%B4%E5%85%8B%E6%98%8E%E6%96%AF%E7%89%B9%E5%AF%8C%E5%8B%92%E7%83%AF#/media/File:Buckminsterfullerene.svg.
14. 維基百科Pentacene, https://zh.wikipedia.org/wiki/%E5%B9%B6%E4%BA%94%E8%8B%AF#/media/File:Pentacene.svg.
15. Ruiz, R., et al., ''Structure of pentacene thin films''. Applied Physics Letters, 2004. 85(21): p. 4926-4928.
16. Kim, B.-s., et al., ''Effect of Dodecane on the Surface Structure and the Electronic Properties of Pentacene on Modified Si (001)''. Applied Science and Convergence Technology, 2016. 25(2): p. 28-31.
17. Ersen Mete, I.l.D.l., M. Fatih Danıs¸man, and S¸inasi Ellialtıog˘lu, ''Pentacene Multilayers on Ag(111) Surface''. J. Phys. Chem., 2010.
18. Werzer, O., et al., ''Full X-ray pattern analysis of vacuum deposited pentacene thin films''. The European Physical Journal B, 2008. 66(4): p. 455-459.
19. Stefan Kowarik, K.B., Alexander Hinderhofer, Adam Schwartzberg, J. Oriol Osso´,| David Kilcoyne, Frank Schreiber, and Stephen R. Leone, ''Crystal Grain Orientation in Organic Homo- and Heteroepitaxy of Pentacene and Perfluoropentacene Studied with X-ray Spectromicroscopy''. J. Phys. Chem., 2010.
20. Jeong-Woo Park, K.-J.B., Jieun Ghim, Seok-Ju Kang, Jeong-Ho Park, and Dong-Yu Kim, ''Effects of Copper Oxide/Gold Electrode as the Source-Drain Electrodes in Organic Thin-Film Transistors''. Electrochem. Solid-State Lett., 2007.
21. Christine C. Mattheus, G.A.d.W., *,†,‡ Robert A. de Groot,†,‡ and Thomas T. M. Palstra†, ''Modeling the Polymorphism of Pentacene''. JACS ARTICLES, 2003.
22. Jurchescu, O.D., J. Baas, and T.T.M. Palstra, ''Effect of impurities on the mobility of single crystal pentacene''. Applied Physics Letters, 2004. 84(16): p. 3061-3063.
23. Yamashita, Y., ''Organic semiconductors for organic field-effect transistors''. Sci Technol Adv Mater, 2009. 10(2): p. 024313.
24. Cheng, H.L., et al., ''Thickness-Dependent Structural Evolutions and Growth Models in Relation to Carrier Transport Properties in Polycrystalline Pentacene Thin Films''. Advanced Functional Materials, 2007. 17(17): p. 3639-3649.
25. Horowitz, G., ''Organic thin film transistors: From theory to real devices''. Journal of Materials Research, 2011. 19(7): p. 1946-1962.
26. Shtein, M., et al., ''Effects of film morphology and gate dielectric surface preparation on the electrical characteristics of organic-vapor-phase-deposited pentacene thin-film transistors''. Applied Physics Letters, 2002. 81(2): p. 268-270.
27. Ruiz, R., ''Thickness Dependence of Mobilityin Pentacene Thin-Film Transistors''. Adv. Mater., 2005.
28. V.Pesavento, P., ''Film and contact resistance in pentacene thin-film transistors: Dependence on film thickness, electrode geometry, and correlation with hole mobility''. Journal of Applied Physics, 2006.
29. Cai, L., et al., ''60Co Gamma–Ray Irradiation Effects on Pentacene-Based Organic Thin-Film Transistors''. Materials Science Forum, 2011. 687: p. 576-579.
30. Neuhold, A., et al., ''X-ray radiation damage of organic semiconductor thin films during grazing incidence diffraction experiments''. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2012. 284: p. 64-68.
31. Wang, C.H., S.W. Chen, and J. Hwang, ''Ordering of pentacene in organic thin film transistors induced by irradiation of infrared light''. Applied Physics Letters, 2009. 95(10).
32. Raval, H.N., et al., ''Investigation of effects of ionizing radiation exposure on material properties of organic semiconducting oligomer – Pentacene''. Organic Electronics, 2013. 14(6): p. 1467-1476.
33. 清大鈷六十輻射照射場, http://thor.site.nthu.edu.tw/.
34. Woods, J.W.T.S.a.R.J., AN INTRODUCTION TO RADIATION CHEMISTRY, Wiley-Interscience,1990
35. Hubbell, J.H., ''Photon Mass Attenuation and Mass Energy-AbsorptioCno efficients for H, C, N, 0, Ar, and Seven Mixtures from 0.1 keV to 20 MeV''. Radiation Research, 1977.
36. 布拉格定律示意圖X-raydiffraction–BrukerD8Discover, http://highscope.ch.ntu.edu.tw/wordpress/?p=41141.
37. X-RAY吸收光譜的三個區域, https://zh.wikipedia.org/wiki/X%E5%B0%84%E7%B7%9A%E5%90%B8%E6%94%B6%E5%85%89%E8%AD%9C#/media/File:XASFig.jpg.
38. Stöhr, J., NEXAFS Spectroscopy. Springer:Berlin, 1992.
39. Fan Zheng, B.-N.P., Soonjoo Seo, Paul G. Evans and F. J. Himpsel, ''Orientation of pentacene molecules on SiO2 : From a monolayer to the bulk''. THE JOURNAL OF CHEMICAL PHYSICS, 2007.
40. 詹丁山, 數據分析步驟簡介「X光吸收光譜暑期訓練營講義」. 2017.
41. NEXAFS, https://www-ssrl.slac.stanford.edu/nexafs.html.
42. 汪建民, 材料分析. 2014.
43. KEITHLEY, KEITHLEY 2400 MANUAL.
44. halleffect圖, http://ezphysics.nchu.edu.tw/prophys/basicexp/expnote/hall/hall_97Feb.pdf.
45. Lin, Y.-J., H.-Y. Tsao, and D.-S. Liu, ''Effects of a metallic front gate on the temperature-dependent electronic property of pentacene films''. Materials Chemistry and Physics, 2014. 148(1-2): p. 431-434.
46. Toshiyuki Kakudate, N.Y., ''Polymorphism in pentacene thin films on SiO2 substrate''. APPLIED PHYSICS LETTERS, 2007.
47. Dimitrakopoulos, C.D., ''Molecular beam deposited thin films of pentacene for organic field effect transistor applications''. J. Appl. Phys., 1996.
48. Günther, A.A., ''Hole mobility in thermally evaporated pentacene: Morphological and directional dependence''. Appl. Phys. Lett., 2015.
49. Klauk, H., et al., ''High-mobility polymer gate dielectric pentacene thin film transistors''. Journal of Applied Physics, 2002. 92(9): p. 5259-5263.
50. Jeong, S.-G., et al., ''Effect of post-fabrication thermal annealing on Fermi-level pinning phenomenon in metal-pentacene junctions''. Organic Electronics, 2012. 13(9): p. 1511-1515.
51. Ji, T., S. Jung, and V.K. Varadan, ''On the correlation of postannealing induced phase transition in pentacene with carrier transport''. Organic Electronics, 2008. 9(5): p. 895-898.