MEMS工艺制备pH-ISFET/REFET功能膜研究

Development of Functional Membranes for pH-ISFET/REFET with MEMS Processes

微电子技术的快速发展,促使硅基传感器向着集成化、微型化、可批量加工方向发展.对于pH-ISFET集成芯片而言,如何以MEMS工艺制备性能优良的pH功能膜,是其发展的关键.目的:以适合批量加工的MEMS工艺研制pH功能膜;方法:在小尺寸集成芯片的基础上,以MEMS工艺分别制备Ta2O5材料的pH敏感膜,PTFE材料的pH钝化膜;结果:在pH1～12范围内,Ta2O5膜pH-ISFET对H+的灵敏度达56mV/pH,PTFE膜REFET对H+的响应仅为0.13mV/pH;结论:采用MEMS工艺,可对以标准CMOS技术加工的ISFET集成芯片系统,进行后续加工,从而实现传感器芯片系统的全过程批量加工.

The fast development of microelectronics has been making sensors based on silicon developing toward integration, microsize and mass production. To the chip integrated with pH-ISFET, fabricating excellent pH functional membrane with MEMS processes is the key factors in development. Fabricating pH sensitive membrane was with MEMS processes,On the base of small size integration chip, Ta2O5 membrane was fabricated as pH sensitive material, and PTFE membrane as pH passive material The sensitivity of the pH-ISFET with Ta2O5 membrane was 56 mV/pH, and the sensitivity of the REFET with PTFE membrane was only 0. 13 mV/pH within the pH range from 1 to 12. It＇s a feasible method to fabricating pH functional membrane with MEMS processes for full integration pH-ISFET chip.