集成电路高精度晶圆测温技术研究

Research on High-Precision Temperature Measurement Techniques for Integrated Circuits

集成电路从硅片制造、电路设计、晶圆加工、封装直到出厂存在近千道工艺,温度始终贯穿其中,温度的精密测量已成为不可或缺的关键技术。针对我国“缺芯少魂”的芯片产业发展困境及集成电路领域对于精密测温的迫切需求,展开传感器选型、长期稳定性考察及标定方法研究,发展多通道高精度测温电路技术,形成测温晶圆标定方法,研制了一套33路有线高精度晶圆温度测量系统。测试结果表明,NTC热敏电阻温度计能够满足高精度晶圆测温需求;拟合温度点的选取对于标定结果具有较大影响,通过不同标定温度点数量及分布的拟合结果比较,最终选取六点拟合,实现了21℃~23℃范围内偏差小于3 mK,测量不确定度7.4 mK(k=2)的结果。

The process of integrated circuit fabrication spans from silicon wafer manufacturing,circuit designing,wafer processing,packaging to the final product,involving nearly a thousand steps where precision temperature control plays a pivotal role.Given the pressing demand for precise temperature measurements in integrated circuit production and the current challenges faced by China's chip industry,this study investigated sensor selection,long-term stability,and calibration methods.Consequently,a multi-channel high-precision temperature measurement circuit technology was developed and a calibration method for temperature measurement wafers was established.Further,a 33-channel wired high-precision wafer temperature measurement system was constructed.Experimental results demonstrate that the NTC thermistor thermometer can satisfy the requirements of high-precision wafer temperature measurements.Calibration results greatly depend on the selection of fitting temperature points.Through comparison of different calibration temperature point distributions and quantities,a six-point fitting was chosen,achieving a deviation less than 3 mK within a 21℃~23℃range,and measurement uncertainty of 7.4 mK(k=2).