涡电流检测仪的电路设计及仿真研究

许多单晶半导体材料的生长都使用了垂直Bridgman法，而在晶体生长过程中对固液界面的位置和形状进行监测虽十分重要却相当困难。为此，根据许多半导体材料的电导系数在固态与液态时相差很大的特性，设计了涡电流检测仪对界面进行检测。针对涡电流检测仪设计了两模拟测量电路，并用protel对它们进行了仿真比较。在截止频率相同的情况下，涡电流检测仪后采用二阶RC有源滤波器纹波较小，效果较好。

Circuit Design and Simulation of Eddy Current Sensor

The vertical Bridgman method (VBM) is widely used in the growth of single crystal semiconductors. Important as it is, the monitoring of solid-liquid interface position and shape in the growing process is very difficult. The large difference between the electrical conductivities of most liquid and solid semiconductors has motivated an exploration of eddy current sensors for the non-invasive sensing of interfaces. Two circuits are designed and simulated by protel. In comparison, the RC active power filter of second order is better.