用激光拉曼谱表征半导陶瓷湿度传感器中晶粒微结构的特性

Characterization of Grain Microstructure in Semiconducting Ceramic Humidity Sensor by Laser Raman Spectroscopy

半导陶瓷湿度传感器是用固相反应和粉末压片烧结的方法制作，它以二氧化锆、二氧化硅、五氧化二磷为主料，并且掺杂三氧化二钇和五氧化二铌．借助于高分辨率的四角和单斜二氧化锆的激光拉曼标准谱，二氧化锆晶粒的微结构显然在未掺杂和用三氧化二钇或五氧化二铌掺杂的样品中分别属于单斜和四角对称晶系．它们在激光显微镜下发出可以区分的不同色彩的荧光．未掺杂的二氧化锆晶粒是线度为１～２μｍ的斜角四边形，而掺杂烧结的晶粒是尺寸大到３～１０μｍ的正方形。

Semiconducting ceramic humidity sensors based on ZrO 2·SiO 2·P 2O 5 doped with Y 2O 3 and Nb 2O 5 were prepared by the solid phase reaction and the pressed powder sintering methods. By means of the high resolution Laser Raman standard spectra of tetragonal and monoclinic zirconia,the zirconia grain microstructures in undoped and Y 2O 3ˉor Nb 2O 5ˉdoped samples were separately belonged to monoclinic and tetragonal symmetrical crystal systems. They emitted distinguishing colour fluoresences under the Laser microscope. The undoped zirconia grain was an oblique quadrangle with size about 1～2 micra,but the doped sintered grain was a square with size up to 3～10 micra,that was beneficial to decrease the resistivity of semiconducting ceramic sensor.