中 文 摘 要
氣體感測器的基本原理是在絕緣材料基板上鍍上一層對待測氣體具感測性質的半導體薄膜，吸附氣體與薄膜材料作用產生導電性質的變化，再量測之。
本實驗以真空蒸鍍熱氧化法製備摻雜貴金屬鋅銦氧化薄膜氣體感測器。實驗過程中首先利用物理氣相沈積法蒸鍍鋅、銦於氧化鋁基板上，再將此薄膜置入高溫爐中進行高溫熱處理及氧化，之後將其置於感測系統中測量其對酒精及一氧化碳之感測度、應答時間及回復時間，並以電子顯微鏡觀察薄膜表面形態。探討在不同蒸鍍速率、氧化條件、原子比例，及以貴重金屬之內部或外部的摻雜下其晶態構造及氣體感測性質隨製程條件及組成變化的情形，同時探討感測的結果與感測機制是否相符及不同工作溫度所產生的效應。
由實驗結果顯示：1.蕭特基接觸及感測氣體與吸附氧離子及晶格氧原子間的反應等感測機制可能同時存在。2.在相同條件下對酒精比對一氧化碳具有更高的感測度。3.對於酒精與一氧化碳分別存在一最佳感測溫度，此溫度分別為3450C與5000C。4.蒸鍍速率較快時，薄膜表面分子明顯結合成較大分子團。5.氧化膜之表面形態及感測度隨原子比而異，對酒精與一氧化碳之感測度，分別在鋅銦原子比為1:1.266與1:0.114時有最佳感測值。6.當氧化速度加快時，薄膜有鬚晶產生。7.內部摻雜貴金屬的結果，感測度呈現下降的趨勢。表面摻雜時，對酒精感測度明顯下降，且回復時間亦有減少的趨勢。

Abstract
The gas sensors consist of a thin film deposited on an electrical insulated substrate, which is sensitive to some gases. Because of the interaction of adsorbed gas with sensor, the sensor electrical properties change, and the change can be detected.
In the study, the ZnO and In2O3 thin films doped with precious metal were prepared by vacuum deposition of a thin film of zinc and indium on Al2O3 substrate followed with thermal annealing and oxidation. The sensitivity, response time, and recovery time for ethanol and CO were measured and the surface morphology is examined by SEM. The sensors were prepared at different rate of deposition, using different atomic ratio, and are oxidized under controlled condition. The effects of operation temperature on the sensitivity were measured and compared with theory. The effects of inner and surface doping of precious metal, manufacturing condition, and compositions on morphology and sensitivity were examined too.
The experimental results show that (1) the underlying mechanisms of the sensitivity probably include Schottky contact and the reactions of sensitive gases with the adsorbed oxygen ion and lattice oxygen, (2) the sensor has a higher sensitivity to ethanol than CO, (3) the sensor has a optimum sensitivity at 3450C and 5000C for ethanol and CO, respectively, (4) larger clusters are produced at higher deposition rate, (5) surface morphology and sensitivity change with atomic ratio, with the best sensitivity at an atomic ratio of Zn to In of 1/1.266 and 1/0.114 for ethanol and CO, respectively, (6) oxidation at higher rate results in a whisker structure on the oxide film, (7) inner doping leads to a decrease in sensitivity, and surface doping leads to an obvious decrease in sensitivity for ethanol and a decrease in recovery time.
Keyword：gas sensor、zinc、indium、thin film、doping

參考文獻
1. T.Takashi, Oxygen sensor, Sensors and Actuators B Vol.14 pp.109 (1988).
2. 鄭煜騰，氣體感測器的市場分析與發展概況，科儀新知第18卷5期76~84頁(1995).
3.曾明漢，觸媒燃燒型氣體感測器，材料與社會第68卷57頁(1992).
4.葉陶淵，化學感測器中氣體感測器的新動向，科儀新知第20卷4期75頁(1999).
5. P.B.Weisz, Effects of electronic charge transfer between adsorbate and solid on chemsiorption and catalysis , J.Chem.Phys Vol.21 pp.1531 ~ 1538 (1953).
6. T.seiyama,A.Kato,K.Fajiishi,M.Nagatahi,A new detector for gaseous components using semiconductive thin films, Analystical chemistry 34 pp.1502 (1962).
7. P.J.Shaver,Activated tungsten oxide gas detectors,Appl. Phys. Lett.,11 pp.255~257(1967).
8. 蔡嬪嬪，氣體感測器的新動向，工業材料150期98頁(1999).
9.李俊遠，氣體感測器介，工業材料124期83頁(1997).
10.W.Gople,Chemical sensor technologies：Empirical art and systematic research, Acomprehensive Survey ,Vol.2 New York：VCH pp.91 (1991).
11. 陳一誠，金屬氧化物半導體型氣體感測器，材料與社會第68期 62~66頁(1992).
12. K.Reichelt And X.Jlang, The Preparation of Thin Film by Physical Vapor Deposition Methods, Thin Solid Films pp.91~26(1990).
13. J.W.Mattews, Epitaxial Growth,, Part B Chapter 4, Acdamic Process (1975).
14. D. R. Uhlmann, B. Chalmers, The energetic of nucleation , American chemical society publication Washington D.C (1996).
15. C.E. Morosanu, Nucleation and Growth of CVD Film, Elsevier Ams- terdam Oxford New York pp.163~164(1990).
16. J.A.Venables,G.D.T.Spiller and M.H.Ken, Nncleation and Growth of Thin film, Report Progress of Physics Vol.47 p349-359 (1984).
17.J.A.Venable and G.L.Price, Epitaxial Growth PartB CH4 pp.381 (1975).
18. N. Yamazoe, J. Fuchigami, M. Kishikawa and T.Seiyama, Interac- tions of tin oxide surface with O2, H2O and H2, Surface Science, Vol. 86 pp.335~344 (1979).
19. S.R.Morrision ,Chemical sensors in Semiconductor Sensors , ed. S.M.Sze ,New York:John Wiley and Sons Inc. pp.383 (1994).
20. H.Windischmann and P.Mark, A model for the operation of a thin film SnOx conductance-modulation carbon monoxide sensor, Journal of the electrochemical society Vol.126 No.4 pp.627~633 (1979).
21. D. Kohl, Surface processes in the detection of reducing gases with SnO2-based devices, Sensors and Actuators Vol.18 pp.71~113 (1989)
22. S. R. Morrison, The Chemical Physics of Surfaces 2nd , New York: Plenum Press pp.251 (1990).
23. N. Yamazoe, J. Fuchigami, M. Kishikawa and T.Seiyama, Interac- tions of tin oxide surface with O2, H2O and H2, Surface Science Vol.86 pp. 335-344 (1979).
24. K. M. Sancier, ESR evidence of CO oxidation by more than one oxygen species sorbed on ZnO, Journal of Catalysis Vol.9 pp. 331~335 (1967).
25. J. F. Mcaleer, P. T. Moseley, J. O. W. Norris and D. E. Williams, Tin dioxide gas sensors, Journal of the Chemical Society. Faraday Trans- actions Vol. 83 pp. 1323~1346 (1987).
26. S. C. Chang, Thin-film semiconductor NOx sensor, IEEE Transac- tions on Electron Devices Vol. ED-26, No. 12 pp. 1875~1880 (1979).
27. G. Heiland, Homogeneous semiconducting gas sensors, Sensors and Actuators Vol.2 pp. 343~361 (1982).
28. G.Sberveglieri,S.Groppelli,P.Nelli&A.Camanzi ,Bismuth-doped tin oxide thin-film gas sensors, Sensors and Actuators B Vol.3 pp183~189 (1991).
29. Kyung.Hyun Cha，Hee Chan Park，Kwang Ho Kim ,Effect of palladium doping and film thickness on the H2-gas sensing chara- cteristics of SnO2, Sensors and Actuators B Vol.21 pp.91~96 (1994).
30. D.A.Neamen, Semiconductor physics and devices, The McGraw-Hill Companies Inc. pp104 (1999).
31. G.C.Bond,M.J.Fuller and L.Molloy, Oxidation of carbon monoxide catalysed by palladium on tin oxide:an example of spillover catalysis, proc.6th Intern.Congr.Catalysis,London U.K. pp356~364 (1988).
32. N.Yamazoe,Y.Kurokawa and T.Seiyama, Effects of additives on sem- iconductor gas sensors , Sensors and Actuators B Vol.4 pp283~289 (1983).
33. S.R.Morrison, Selectivity in semiconductor gas sensors, Sensors and Actuators B Vol.12 pp.425 (1987).
34. Colin J. Smithells, Vapor pressure in Metal s Reference Book, London and Boston：Butterworths pp.231 (1967).
35. J. Watson, A note on the electrical characterization of solid-state gas sensors, Sensors and Actuators B Vol. 8 pp. 173~177 (1992).
36. F.Reti,M.Fleischer,H.Meixner and J.Giber, Influence of water on the coadsorption of oxidizing and reducing gases on the β–Ga2O3 surface, Sensors and Actuators B Vol.18-19 pp.138~142 (1994).
37. N.Barsen and R.Ionescu, The mechanism of the interaction between CO and an SnO2 surface: the role of water vapor ,Sensors and Actu- ators B Vol.12 pp.71~75 (1993) .
38.Andrew P.Lee, Temperature modulation in semiconductor gas sensing, Sensors and Actuator B Vol.60 pp35~42 (1999).
39. P.T.Moseley , Materials selection for semiconductor gas sensors, Sen- sors and Actuators B Vol.6 pp.149-156 (1992).
40. IRA N. Levine, Physical chemistry 4th edition, McGraw-Hill, New York pp443(1995).
41. R Bene, Application of quadrupole mass spectromter for the analysis of near-surface gas composition during DC sensor-tests, Vacuum Vol. 50 number3-4 pp.331~337 (1998).
42. D.Kohl, Adsorption and decomposition of methane on gallium oxide films, Sensors and Actuator B Vol.59 pp140~145 (1999).
43.G.Gaggiotti, Temperature dependencies of sensitivity and surface chemical composition of SnO gas sensor, Sensors and Actuators B Vol.24-25 pp516~519 (1995).
44.J.Mizsei, How can sensitive and selective semiconductor gas sensors be made, Sensors and Actuators B Vol.23 pp173~176 (1995).
45. G. Sberveglieri,S. Groppelli, P. Nelli, A. Tintinelli, G. Giunta, A no- vel method for the proparation of NH3 sensors based on ZnO-In thin films ,Sensors and Actuators B Vol.24-25 pp.588-590 (1995) .
45. Toshihiro Miyata, High sensitivity chlorine gas sensor using multi- component transparent conducting oxide thin film, Sensors and Actuators B Vol.69 pp.16~21(2000).
47. G.Sberveglieri, Response to nitric oxide of thin and thick SnO2 film containing trivalent additives, Sensors and Actuators B Vol.1 pp.79~82 (1990).
48. R.D. Doherty, Dendritic growth in crystal growth, ed. Brian R. Pamp- lin , New York：Pergamon pp.485 (1980).
49. D.KOHL, The role of noble metals in the chemistry of solid-state gas sensor, Sensors and Actuators B Vol.1 pp.158~165 (1990).
50.W.P. Kang, Catalyst adsorptive oxide semiconductor gas sensors, Sen- sors and Actuators B Vol.13~14 pp.682~684 (1993).
51.吳榮宗，過渡金屬特性與催化活性，工業觸媒概論第六章102~112頁 (1983).
52.Shigenori, Matsushina, New methods for supporting palladium on tin oxide gas sensor, Sensors and Actuators B Vol.9 pp.71~78(1992)