MECHANICAL SENSORS BASED ON LASER-RECRYSTALLIZED SOI STRUCTURES

Application of microzone laser recrystallization in the technology of microelectronic mechanical sensors is considered. Recent results conce rning theoretical and experimental studies of recrystallized polycryst alline silicon on insulator resistors, improvement of pressure-sensor performance and creation of microelectronic sensors of force and accel eration are reported. It is shown theoretically and proved experimenta lly that dopant impurity (boron) concentrations of 1 X 10(18)-1 X 10(1 9) cm(-3) are the most advisable to apply laser recrystallization for the improvement of poly-Si resistors and mechanical sensors based on t hem. At dopant levels of 1 X 10(18)-5 X 10(18) cm(-3) the gauge factor increases 1.5-1.7 times due to the laser recrystallization, whilst th e temperature characteristics of poly-Si resistors (temperature coeffi cient of resistivity and temperature coefficient of the gauge factor) decrease. Advantages of the developed mechanical sensors are high-temp erature operating range, possibility to select the temperature coeffic ients by the choice of doping concentrations in polysilicon layers and reproducibility of the sensor fabrication process.