硅基纳米湿敏元件特性、机理研究及其测试仪设计
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摘要
以硅片为衬底制作了纳米钛酸钡(BaTiO_3)膜湿敏元件。用硬脂酸盐法合成纳米钛酸钡材料，丝网印刷法将纳米钛酸钡涂在硅衬底上制成电阻式湿敏元件。测试分析了元件的性能参数，结果表明，元件具有较高的灵敏度。元件阻抗(Z)和电容(C)值随测试频率及相对湿度(RH)而变化，但基本不随测试电压变化。在1V，100Hz条件下，元件阻抗～相对湿度关系曲线的线性最好。
用复阻抗法对硅衬底纳米钛酸钡湿敏元件的感湿机理进行了分析讨论。实验测量得到湿敏元件在不同相对湿度下的复阻抗特性曲线，然后用各种理想等效电路的复阻抗曲线与实际测量的纳米钛酸钡湿敏元件的复阻抗特性曲线进行比较，寻找一组最相近的曲线。结果表明，纳米钛酸钡湿敏元件的感湿特性可以等效为两个电阻—电容并联电路的串联再与另一个电阻串联的等效电路。这个电路在改变电阻与电容参数的情况下，复阻抗特性曲线的变化规律可以很好的与纳米钛酸钡湿敏元件的实验测量的不同湿度下复阻抗特性曲线的变化规律相吻合。分析出相应的等效电路之后，结合等效电路有关参数的变化规律，分析讨论了纳米钛酸钡湿敏元件的感湿机理。低湿时，感湿材料本身颗粒电阻和电容(传导载流子和材料极化)及吸附的少量水分子共同起作用；高湿时，吸附的水分子的电离及水分子引起的电极处的空间电荷极化起主要作用。
纳米钛酸钡感湿芯片是一种电阻式湿度传感器。100Hz交流电压作用下，该感湿芯片的输出电阻值对数与相对湿度之间的线性最好，且在相对湿度11％～98％范围内其阻值变化了4个数量级，感湿灵敏度较高。但是，电阻跨度大成为测湿电路设计的难题。本论文基于单片机AT89C2051，采用程控放大技术，设计了简单化、智能化的湿度测试仪，有效解决了上述难题。
The humidity sensor is fabricated with nanometer BaTiO3 film on silicon substrate. The nanometer BaTiO3 is synthesized by stearic acid method and is screen printed on silicon substrate to make the resistive type humidity sensor. The properties of the sensor were measured and analyzed. The results show that the sensor processes high sensitivity. The measurement voltage does not influence the properties of the sensor, while the impedance and the capacitance of the sensor change with the relative humidity (RH) and the measurement frequency. The best linearity of the impedance vs. RH curve is reached under the voltage 1V and the frequency 100Hz.
Complex impendence techniques are used to analyze the humidity sensing mechanism of nanometer barium titanate humidity sensors on silicon substrate. The curves of resistance, capacitance and complex impedance of the sensors versus relative humidity (RH) are measured at different frequencies. An equivalent circuit model associated with resistors and capacitors is built. The complex impedance properties of the equivalent circuit changing with parameters of the resistance and the capacitance are coincident with complex impedance properties of BaTiO3 humidity sensor changing with RH in practice. The sensing mechanism of the sensor is discussed. In low RH range, the humidity sensing properties are determined mainly by the crystal grain resistance and the capacitance on the grain interfaces. In high humidity RH range, the polarization and ionization of the absorbed water makes a main contribution to humidity sensing properties.
Nanometer barium titanate humidity sensor is a resistive sensor. The resistance changes from 103 to 106 in the RH range of 11%-98%, which shows the high sensitivity of sensor. A simple, intelligent, precision humidity measuring instrument is designed by using singlechip AT89C2051, programmable gain amplifier technology. The difficult design problems of wide resistance changing range are solved.
用复阻抗法对硅衬底纳米钛酸钡湿敏元件的感湿机理进行了分析讨论。实验测量得到湿敏元件在不同相对湿度下的复阻抗特性曲线，然后用各种理想等效电路的复阻抗曲线与实际测量的纳米钛酸钡湿敏元件的复阻抗特性曲线进行比较，寻找一组最相近的曲线。结果表明，纳米钛酸钡湿敏元件的感湿特性可以等效为两个电阻—电容并联电路的串联再与另一个电阻串联的等效电路。这个电路在改变电阻与电容参数的情况下，复阻抗特性曲线的变化规律可以很好的与纳米钛酸钡湿敏元件的实验测量的不同湿度下复阻抗特性曲线的变化规律相吻合。分析出相应的等效电路之后，结合等效电路有关参数的变化规律，分析讨论了纳米钛酸钡湿敏元件的感湿机理。低湿时，感湿材料本身颗粒电阻和电容(传导载流子和材料极化)及吸附的少量水分子共同起作用；高湿时，吸附的水分子的电离及水分子引起的电极处的空间电荷极化起主要作用。
纳米钛酸钡感湿芯片是一种电阻式湿度传感器。100Hz交流电压作用下，该感湿芯片的输出电阻值对数与相对湿度之间的线性最好，且在相对湿度11％～98％范围内其阻值变化了4个数量级，感湿灵敏度较高。但是，电阻跨度大成为测湿电路设计的难题。本论文基于单片机AT89C2051，采用程控放大技术，设计了简单化、智能化的湿度测试仪，有效解决了上述难题。
The humidity sensor is fabricated with nanometer BaTiO3 film on silicon substrate. The nanometer BaTiO3 is synthesized by stearic acid method and is screen printed on silicon substrate to make the resistive type humidity sensor. The properties of the sensor were measured and analyzed. The results show that the sensor processes high sensitivity. The measurement voltage does not influence the properties of the sensor, while the impedance and the capacitance of the sensor change with the relative humidity (RH) and the measurement frequency. The best linearity of the impedance vs. RH curve is reached under the voltage 1V and the frequency 100Hz.
Complex impendence techniques are used to analyze the humidity sensing mechanism of nanometer barium titanate humidity sensors on silicon substrate. The curves of resistance, capacitance and complex impedance of the sensors versus relative humidity (RH) are measured at different frequencies. An equivalent circuit model associated with resistors and capacitors is built. The complex impedance properties of the equivalent circuit changing with parameters of the resistance and the capacitance are coincident with complex impedance properties of BaTiO3 humidity sensor changing with RH in practice. The sensing mechanism of the sensor is discussed. In low RH range, the humidity sensing properties are determined mainly by the crystal grain resistance and the capacitance on the grain interfaces. In high humidity RH range, the polarization and ionization of the absorbed water makes a main contribution to humidity sensing properties.
Nanometer barium titanate humidity sensor is a resistive sensor. The resistance changes from 103 to 106 in the RH range of 11%-98%, which shows the high sensitivity of sensor. A simple, intelligent, precision humidity measuring instrument is designed by using singlechip AT89C2051, programmable gain amplifier technology. The difficult design problems of wide resistance changing range are solved.
引文
[1] 刘迎春，叶湘滨编著．现代新型传感器原理与应用．第一版．北京：国防工业出版社，1998年1月．297
[2] 单成祥编著．传感器的理论与设计基础及其应用．第一版．北京：国防工业出版社，1999．467-468
[3] 单成祥编著．传感器的理论与设计基础及其应用．第一版．北京：国防工业出版社，1999．468
[4] 单成祥编著．传感器的理论与设计基础及其应用．第一版．北京：国防工业出版社，1999．189
[5] 刘迎春，叶湘滨编著．现代新型传感器原理与应用．第一版．北京：国防工业出版，1998年1月．191-192
[6] 高清桥，小长井诚编著，秦起佑，蒋冰，徐同举等译校．传感器电子学．北京：宇航出版社，1999．469
[7] 康昌鹤，唐省吾等编著．气、湿敏器件及其应用．北京：科学出版社，1988．210-216
[8] A.M..taurino, S.Capone, Psiciliano, T.Toccoli et al..Nanostructured TiO_2 thin film prepaid by supersonic beams and their application in a sensor array for the discrimibation of VOC. Sensor and Actuator B, 2003, Vol.92:292-302
[9] W.Cun, Z.Jincai, et al., Preparation characterization and photocatalytic activity of nano-sized ZnO/SnO_2 coupled photocatalysts. Appl. Cata, 2002, Environ:1-11
[10] Li.G.Q, Lai.P.T, Zheng.S.H, Huang.M.Q and Liu.B.Y. Effect of chemical composition on humidity sensitivity of Al/BaTiO_3/Si structure. Appl. Phys. Let., 1995,Vol.6:2436-2438
[11] Chen S N, Ramarkrishnan E S, Huang R S, et al. A new thin film humidity micro-sensor. IEEE Electron Device Lett., 1984, DEL-5:452-453
[12] Sager K, Gerlach G, Schroyh A. A humidity sensor of new type. Sensors and Actuators B, 1995,Vol. 23: 177-180
[13] Li.G.Q, Huang.M.Q, Zheng.S.H, et. al.. A new thin film humidity and thermal micro-sensor with Al/SrNb_xTi_(1-x)O_3/SiO_2/Si sructure. Sensor and Actuators B, 1995,Vol.23:177-180
[14] Chow L L N, Tuen M M. Reactive sputtered TiO_2 thin film humidity sensor with negative substrate bias. Sensors and Actuators B, 2001,vol,76:304-309
[15] Li.G.Q, Lai.P.T, Zheng.S.H, Huang.M.Q and Cheng.Y.C. Photo, Thermal and humidity sensitivity characteristics of Sr_(1-x)La_xTiO_3 film on SiO_2/Si substrate. Sensors and Actuators A, 1997, Vol. 639:223-226.
[16] G.Sberveglieri, R.Murri, N.Pinto. Characterization of porous Al_2O_3-SiO_2/Si sensor for low and medium humidity ranges. Sensors and Actuators B 1995,Vol.23:177-180
[17] T.Seiyama, N.Yamazoe, H.Arai Ceramic humidity sensors. Sensors and Actuators, 1983,Vol.4:85-95
[18] Y.Shimizu, M.Shimabuku ro, H.Arai, T.Seiyama. Enhancement of humidity sensitivity for perovskitetype oxides having semiconducttivity. Chem. Lett., 1985,Vol.7:917-920
[19] Li.G.Q, Huang.M.Q, Zheng.S.H, Sensitivity of humidity and its mechanism for SrTiO_3 films deposited on SiO_2/Si substrate. Acta Physica Sinica, 1998,Vol.47(1):160-167
[20] 王子枕，王晓慧，杨桦等．BaTiO_3纳米晶的湿敏特性研究．功能材料，1996，27(3)：258-260
[21] 陈秀芳，莫茂松等．纳米级La_(1-x)Ba_xCoO_3半导体陶瓷的制备与湿敏性能．无锡轻工大学学报，2001，vol．20(3)：261-264
[22] Wang Jing, Xu Bao Kun, Ruan Ping Sheng, Wang Shi Ping. Preparation and electrical properties of the
humidity sensing films of BaTiO_3/polystyrene sulfonic sodium. Materials Chemistry and Physics, 2003,Vol.78:746-750
[23] Hwang T J, Choi G M. Humidity response characteristics of barium titanate. J.Am. Ceram. Soc., 1993,Vol.76:766-768
[24] Huang H J, Shushtarian S S, Kanetkar S M, et al., Humidity sensitivity of La~+-doped BaTiO_3 semiconductor thin film deposited by pilsed excimer laser ablation. J.Mater.Sci.Lett.,1993,vol. 12:63-65
[25] H.A.Saner and J.R.Fisher. Processing of positive temperature coefficient thermistors. J.Am. Ceram. Soc., 1960,Vol.43:297-300
[26] Seema Agarwal, G.L.Sharma. Humidity sensing properties of (Ba, Sr)TiO_3 thin films grown by hydrothermal-electrochemical method. Sensors and Actuators B, 2002,Vol.86:205-211
[27] Wang J, Xu B, Liu G, et al.. Improvement of nanocrastal BaTiO_3 humidity sensing properties, sensors and Acuators B, 2000,Vol.66:159-160
[28] G.V.Lewis, C.R.A., Catlow and R.E.W. Casselton. PTCR effect in BaTiO_3. J.AM. Ceram. Soc., 1985 Vol.68:555-558
[29] Wang J, Xu B, Liu G, et al.. Influence of doping on humidity sensing properties of nanocrystal BaTiO_3. J.Mater.Sci.Lett., 1998,Vol.17:875-859
[30] Wang J, Lin Q, Zhou R, et al.. Humidity sensors based on composite material of nano- BaTiO_3 and polymer RMX. Sensors and Actuators B, 2002,Vol.81:248-253.
[31] 牛德芳等编著．半导体传感器及其应用．第一版．大连：大连理工大学出版社，1993年2月．197-198
[32] Wu.M.T, Sun H.T, Li.P. CuO-doped ZnCr_2 O_4-LiZnVO_4 thick-film humidity sensor. Sensors and Actuators B, 1994,Vol.17:109-112
[33] 张彤，徐宝琨等．用直流、交流方法分析高分子电阻型湿敏元件的敏感机理．传感技术学报，2001，Vol．2：129-133
[34] Yen Y C, Tseng T Y. Analysis of the d.c. and a.c. properties of K_2O-doped porous Ba_(0.5)Sr_(0.5)TiO_3 ceramic humidity sensor. J. Mater.Sci., 1989,Vol.24:2739-2745
[35] 方佩敏编著．新编传感器原理·应用·电路祥解．第一版．北京：电子工业出版社，1994年10月．45-47
[36] 刘迎春编著．传感器原理 设计与应用．第一版．湖南：国防科技大学出版社，1989年2月．228
[37] Chen ZhiWei, Liu Bohua. Complex impendance analysis of humidity-sebsitive mechanism on Ti-AL-Li materials. Xian: Proceeding of the second East Asia Conference on Chemical Sensor, 1995.221-223
[38] Feng.C.D,Sun.S.L,Wang.H, C.U.Sagre, Sagre.C.U, J.R.Stetter. Sensors and Actuators B, Vol.40, 1997:217
[39] 张靖漓，卢跃东，吴国标等．La_(1-x)Sr_xFeO_3系电子陶瓷的湿敏特性的研究．无机材料学报，1992，Vol．37(1)：37-41
[40] Bondaremka V, Grebinskij S, Mickevicius S,et al.. Humidity sensors based on H_2V_(11)TiO_(30.3)·nH_2O xerogels. Sensora and Actuators B, 1999,Vol.55:60-64
[41] Traversa E, Gnappi G, Montenero A, et al.. Ceramic thin films by sol-gel processing as novel materials for integrated humidity sensors. Sensors and Actuators B, 1996,Vol;31:59-70
[42] Janez Holc, Jaroslav Slunecko, Marko Hrovat. Temperature characteristics of electrical properties of (Ba, Sr)TiO_3 thick film humidity sensors. Sensors and Actuators B, 1995,Vol.26:99-102
[43] V.Bondarenka, S.Grebinskij, S.Mickevcius, V.VolkovG. Zacharova. Thin films of poly vanadium molybdenum acid as starting materials for humidity sensors. Sensors and Actuators B, 1995,Vol.28: 227-231
[44] 张靖漓，卢跃东，吴国标．用复阻抗法分析MgCr_2O_4-TiO_2湿敏陶瓷感湿机理．传感技术学报，1993，Vol．3：37—40
[45] 张良莹，姚熹编著．电介质物理．第一版．西安：西安交通大学出版社，1990年6月．170-171
[46] 张良莹，姚熹编著．电介质物理．第一版．西安：西安交通大学出版社，1990年6月．172-173
[47] 王兢，吴英奎，万徽．硅衬底纳米钛酸钡湿敏元件分析．大连理工大学学报，2003，Vol．43(7)：522-526
[48] 胡在华，彭楚武，夏一翔．测控系统中智能式温湿度传感器的实现．传感器世界，2001，Vol．2：39-42
[49] 翟俊祥．PGA204／205可编程增益放大器的原理和应用．国外电子元器件，1999，Vol．5：36-38
[50] 姚嘉．单片12位数据采集系统MAX187及应用．国外电子元器件，1996，Vol．10：9-12
[51] 黎民．数字万用表的制作与使用．香港：万里书店有限公司，1983年9月．59-61
[52] 黄维荣．MAX7219在智能仪表中的应用．电子技术，1997，Vol．8：384-387
[53] 王祁，聂伟，于航．智能传感器常用软件及设计．传感器技术，1998，Vol．17(3)：49-51
[54] 赵新民．智能仪器设计基础．哈尔滨：哈尔滨工业大学出版社，1999
[55] 吴晓帆，康珏，蔡自兴．传感输出信号的线性化处理．自动化仪表．1998，Vol．19(7)：37-39
[2] 单成祥编著．传感器的理论与设计基础及其应用．第一版．北京：国防工业出版社，1999．467-468
[3] 单成祥编著．传感器的理论与设计基础及其应用．第一版．北京：国防工业出版社，1999．468
[4] 单成祥编著．传感器的理论与设计基础及其应用．第一版．北京：国防工业出版社，1999．189
[5] 刘迎春，叶湘滨编著．现代新型传感器原理与应用．第一版．北京：国防工业出版，1998年1月．191-192
[6] 高清桥，小长井诚编著，秦起佑，蒋冰，徐同举等译校．传感器电子学．北京：宇航出版社，1999．469
[7] 康昌鹤，唐省吾等编著．气、湿敏器件及其应用．北京：科学出版社，1988．210-216
[8] A.M..taurino, S.Capone, Psiciliano, T.Toccoli et al..Nanostructured TiO_2 thin film prepaid by supersonic beams and their application in a sensor array for the discrimibation of VOC. Sensor and Actuator B, 2003, Vol.92:292-302
[9] W.Cun, Z.Jincai, et al., Preparation characterization and photocatalytic activity of nano-sized ZnO/SnO_2 coupled photocatalysts. Appl. Cata, 2002, Environ:1-11
[10] Li.G.Q, Lai.P.T, Zheng.S.H, Huang.M.Q and Liu.B.Y. Effect of chemical composition on humidity sensitivity of Al/BaTiO_3/Si structure. Appl. Phys. Let., 1995,Vol.6:2436-2438
[11] Chen S N, Ramarkrishnan E S, Huang R S, et al. A new thin film humidity micro-sensor. IEEE Electron Device Lett., 1984, DEL-5:452-453
[12] Sager K, Gerlach G, Schroyh A. A humidity sensor of new type. Sensors and Actuators B, 1995,Vol. 23: 177-180
[13] Li.G.Q, Huang.M.Q, Zheng.S.H, et. al.. A new thin film humidity and thermal micro-sensor with Al/SrNb_xTi_(1-x)O_3/SiO_2/Si sructure. Sensor and Actuators B, 1995,Vol.23:177-180
[14] Chow L L N, Tuen M M. Reactive sputtered TiO_2 thin film humidity sensor with negative substrate bias. Sensors and Actuators B, 2001,vol,76:304-309
[15] Li.G.Q, Lai.P.T, Zheng.S.H, Huang.M.Q and Cheng.Y.C. Photo, Thermal and humidity sensitivity characteristics of Sr_(1-x)La_xTiO_3 film on SiO_2/Si substrate. Sensors and Actuators A, 1997, Vol. 639:223-226.
[16] G.Sberveglieri, R.Murri, N.Pinto. Characterization of porous Al_2O_3-SiO_2/Si sensor for low and medium humidity ranges. Sensors and Actuators B 1995,Vol.23:177-180
[17] T.Seiyama, N.Yamazoe, H.Arai Ceramic humidity sensors. Sensors and Actuators, 1983,Vol.4:85-95
[18] Y.Shimizu, M.Shimabuku ro, H.Arai, T.Seiyama. Enhancement of humidity sensitivity for perovskitetype oxides having semiconducttivity. Chem. Lett., 1985,Vol.7:917-920
[19] Li.G.Q, Huang.M.Q, Zheng.S.H, Sensitivity of humidity and its mechanism for SrTiO_3 films deposited on SiO_2/Si substrate. Acta Physica Sinica, 1998,Vol.47(1):160-167
[20] 王子枕，王晓慧，杨桦等．BaTiO_3纳米晶的湿敏特性研究．功能材料，1996，27(3)：258-260
[21] 陈秀芳，莫茂松等．纳米级La_(1-x)Ba_xCoO_3半导体陶瓷的制备与湿敏性能．无锡轻工大学学报，2001，vol．20(3)：261-264
[22] Wang Jing, Xu Bao Kun, Ruan Ping Sheng, Wang Shi Ping. Preparation and electrical properties of the
humidity sensing films of BaTiO_3/polystyrene sulfonic sodium. Materials Chemistry and Physics, 2003,Vol.78:746-750
[23] Hwang T J, Choi G M. Humidity response characteristics of barium titanate. J.Am. Ceram. Soc., 1993,Vol.76:766-768
[24] Huang H J, Shushtarian S S, Kanetkar S M, et al., Humidity sensitivity of La~+-doped BaTiO_3 semiconductor thin film deposited by pilsed excimer laser ablation. J.Mater.Sci.Lett.,1993,vol. 12:63-65
[25] H.A.Saner and J.R.Fisher. Processing of positive temperature coefficient thermistors. J.Am. Ceram. Soc., 1960,Vol.43:297-300
[26] Seema Agarwal, G.L.Sharma. Humidity sensing properties of (Ba, Sr)TiO_3 thin films grown by hydrothermal-electrochemical method. Sensors and Actuators B, 2002,Vol.86:205-211
[27] Wang J, Xu B, Liu G, et al.. Improvement of nanocrastal BaTiO_3 humidity sensing properties, sensors and Acuators B, 2000,Vol.66:159-160
[28] G.V.Lewis, C.R.A., Catlow and R.E.W. Casselton. PTCR effect in BaTiO_3. J.AM. Ceram. Soc., 1985 Vol.68:555-558
[29] Wang J, Xu B, Liu G, et al.. Influence of doping on humidity sensing properties of nanocrystal BaTiO_3. J.Mater.Sci.Lett., 1998,Vol.17:875-859
[30] Wang J, Lin Q, Zhou R, et al.. Humidity sensors based on composite material of nano- BaTiO_3 and polymer RMX. Sensors and Actuators B, 2002,Vol.81:248-253.
[31] 牛德芳等编著．半导体传感器及其应用．第一版．大连：大连理工大学出版社，1993年2月．197-198
[32] Wu.M.T, Sun H.T, Li.P. CuO-doped ZnCr_2 O_4-LiZnVO_4 thick-film humidity sensor. Sensors and Actuators B, 1994,Vol.17:109-112
[33] 张彤，徐宝琨等．用直流、交流方法分析高分子电阻型湿敏元件的敏感机理．传感技术学报，2001，Vol．2：129-133
[34] Yen Y C, Tseng T Y. Analysis of the d.c. and a.c. properties of K_2O-doped porous Ba_(0.5)Sr_(0.5)TiO_3 ceramic humidity sensor. J. Mater.Sci., 1989,Vol.24:2739-2745
[35] 方佩敏编著．新编传感器原理·应用·电路祥解．第一版．北京：电子工业出版社，1994年10月．45-47
[36] 刘迎春编著．传感器原理 设计与应用．第一版．湖南：国防科技大学出版社，1989年2月．228
[37] Chen ZhiWei, Liu Bohua. Complex impendance analysis of humidity-sebsitive mechanism on Ti-AL-Li materials. Xian: Proceeding of the second East Asia Conference on Chemical Sensor, 1995.221-223
[38] Feng.C.D,Sun.S.L,Wang.H, C.U.Sagre, Sagre.C.U, J.R.Stetter. Sensors and Actuators B, Vol.40, 1997:217
[39] 张靖漓，卢跃东，吴国标等．La_(1-x)Sr_xFeO_3系电子陶瓷的湿敏特性的研究．无机材料学报，1992，Vol．37(1)：37-41
[40] Bondaremka V, Grebinskij S, Mickevicius S,et al.. Humidity sensors based on H_2V_(11)TiO_(30.3)·nH_2O xerogels. Sensora and Actuators B, 1999,Vol.55:60-64
[41] Traversa E, Gnappi G, Montenero A, et al.. Ceramic thin films by sol-gel processing as novel materials for integrated humidity sensors. Sensors and Actuators B, 1996,Vol;31:59-70
[42] Janez Holc, Jaroslav Slunecko, Marko Hrovat. Temperature characteristics of electrical properties of (Ba, Sr)TiO_3 thick film humidity sensors. Sensors and Actuators B, 1995,Vol.26:99-102
[43] V.Bondarenka, S.Grebinskij, S.Mickevcius, V.VolkovG. Zacharova. Thin films of poly vanadium molybdenum acid as starting materials for humidity sensors. Sensors and Actuators B, 1995,Vol.28: 227-231
[44] 张靖漓，卢跃东，吴国标．用复阻抗法分析MgCr_2O_4-TiO_2湿敏陶瓷感湿机理．传感技术学报，1993，Vol．3：37—40
[45] 张良莹，姚熹编著．电介质物理．第一版．西安：西安交通大学出版社，1990年6月．170-171
[46] 张良莹，姚熹编著．电介质物理．第一版．西安：西安交通大学出版社，1990年6月．172-173
[47] 王兢，吴英奎，万徽．硅衬底纳米钛酸钡湿敏元件分析．大连理工大学学报，2003，Vol．43(7)：522-526
[48] 胡在华，彭楚武，夏一翔．测控系统中智能式温湿度传感器的实现．传感器世界，2001，Vol．2：39-42
[49] 翟俊祥．PGA204／205可编程增益放大器的原理和应用．国外电子元器件，1999，Vol．5：36-38
[50] 姚嘉．单片12位数据采集系统MAX187及应用．国外电子元器件，1996，Vol．10：9-12
[51] 黎民．数字万用表的制作与使用．香港：万里书店有限公司，1983年9月．59-61
[52] 黄维荣．MAX7219在智能仪表中的应用．电子技术，1997，Vol．8：384-387
[53] 王祁，聂伟，于航．智能传感器常用软件及设计．传感器技术，1998，Vol．17(3)：49-51
[54] 赵新民．智能仪器设计基础．哈尔滨：哈尔滨工业大学出版社，1999
[55] 吴晓帆，康珏，蔡自兴．传感输出信号的线性化处理．自动化仪表．1998，Vol．19(7)：37-39