摘要
本文介绍了氢离子敏场效应晶体管的温度特性,分析了敏感膜-溶液间的界面电势差及其温度系数,并采用线性近似法提出了反映溶液pH 值与输出电压、温度和器件常数之间关系的表达式。介绍了一种可以测量pH 值与温度的微机温度补偿系统。采用温度特性已知的标准缓冲液标定常数后,就可对待测液进行测量。标定与测量均可自动进行。研究表明该系统可以在pH 值很宽的范围进行补偿。在pH4.00、6.86与9.20标准缓冲液中,温度由5℃变至45℃过程中,温度造成的误差仅为未补偿时的1/40,相当于0.001PH/℃。
The temperature characteristics of pH-ISFET are introduced.The interracial potential developed between ion sensitive film and solution andits temperature coefficient has been analyzed.Based on the linear approxima-tion,the expression of pH value with the output voltage,the solution tempe-rature and device constants has been derived.An experimental microprocessortemperature compensation system,which can measure the solution tempera-ture and pH value was built up.After calibration of the device constants,the system is ready for measurement,The calibration and measuring proce-dures are completed automatically.Experimental results have shown,that thetemperature compensation technique is suitable for solutions of wide pH range.The temperature drift of the whole system drops down to 0.001 pH/℃ in stan-dard buffer solutions of pH 4.00,6.86 and 9.20,for temperature from 5to45℃,which is 40 times less than the temperature drift of the same pH-ISFETwithout temperature compensation.
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
1989年第3期304-309,共6页
Chinese Journal of Scientific Instrument
