公开(公告)号：US20150078416A1

公开(公告)日：2015-03-19

申请号：US14490430

申请日：2014-09-18

Applicant: TOKYO ELECTRON LIMITED

Inventor： Jun PEI ,  Junwei BAO ,  Holger TUITJE ,  Ching-Ling MENG ,  Mihail D. MIHAYLOV

IPC: G01K11/24 ,  H01L21/66

CPC classification number: G01K11/24 ,  H01L21/67248

Abstract: Disclosed is a method and apparatus for measuring semiconductor substrate temperature using a differential acoustic time of flight measurement technique. The measurement is based on measuring the time of flight of acoustic (ultrasonic) waves across the substrate, and calculating a substrate temperature from the measured time of flight and the known temperature dependence of the speed of sound for the substrate material. The differential acoustic time of flight method eliminates most sources of interference and error, for example due to varying coupling between an ultrasonic transducer and the substrate. To further increase the accuracy of the differential acoustic time of flight measurement, a correlation waveform processing algorithm is utilized to obtain a differential acoustic time of flight measurement from two measured ultrasonic waveforms. To facilitate signal recognition and processing, a symmetric Lamb mode may be used as mode of excitation of the substrate.

Abstract translation: 公开了一种使用飞行测量技术的差分声学时间来测量半导体衬底温度的方法和装置。 该测量基于测量穿过基底的声波（超声波）的飞行时间，以及从测量的飞行时间和基底材料的声速的已知温度依赖性来计算基底温度。 差分声学时间飞行方法消除了大量的干扰和误差源，例如由于超声换能器和基底之间的耦合变化。 为了进一步提高差分声学时间飞行测量的精度，利用相关波形处理算法从两个测量的超声波波形获得飞行测量的差分声学时间。 为了便于信号识别和处理，可以使用对称的兰姆模式作为衬底的激发模式。