Thin-film resistance thermometers on silicon wafers

Kenneth G Kreider, Dean C Ripple, William A Kimes
2009 Measurement science and technology  
We have fabricated Pt thin-film resistors directly sputtered on silicon substrates to evaluate their use as resistance thermal detectors (RTDs). This technique was chosen to achieve more accurate temperature measurements of large silicon wafers during semiconductor processing. High purity (0.999968 mass fraction) platinum was sputter deposited on silicon test coupons using titanium and zirconium bond coats. These test coupons were annealed and four-point resistance specimens were prepared for
more » ... ermal evaluation. Their response was compared with calibrated platinum-palladium thermocouples in a tube furnace. We evaluated the effects of furnace atmosphere, thinfilm thickness, bond coats, annealing temperature, and peak thermal excursion of the Pt thin films. Secondary ion mass spectrometry (SIMS) was performed to evaluate the effect of impurities on the thermal resistance coefficient, α. We present typical resistance versus temperature curves, hysteresis plots versus temperature and an analysis of the causes of uncertainties in the measurement of seven test coupons. We conclude that sputtered thin-film platinum resistors on silicon wafers can yield temperature measurements with uncertainties of less than 1 °C, k=1 up to 600 °C. This is comparable or better than commercially available techniques.
doi:10.1088/0957-0233/20/4/045206 fatcat:hifhkc2bv5batn4eul5kypz6y4