STRESS MEASUREMENTS OF RADIOFREQUENCY REACTIVELY SPUTTERED RUO2 THIN-FILMS

The stress-temperature behaviors of RuO2 thin films on (100) Si were i nvestigated by measuring the deflection of film-coated substrates in s itu during thermal cycling between 25 and 700 degrees C. The average b iaxial elastic modulus [E/(1 - nu)] and thermal expansion coefficient (alpha) of RuO2 thin film were also determined using the stress-temper ature curves of the films on both (100) Si and quartz substrates. For this study, RuO2 thin films were deposited by rf magnetron reactive sp uttering at the substrate temperature range of 25-450 degrees C. As-gr own thin films deposited between 300 and 450 degrees C showed differen t stress-temperature behavior, which was caused mainly by the microstr ucture of the thin films. The values of [E/(1 - nu)](RuO2) and alpha(R uO2) were calculated to 3.09 X 10(11) Pa and 10.47 X 10(-6)/degrees C, respectively, in the range of 350-600 degrees C. The alpha(RuO2) obta ined from the stress data was compared with the alpha value calculated from the thermal expansion coefficient, alpha(a) and alpha(c), of RuO 2 single crystal. Both values were found to be in good agreement. (C) 1996 American Institute of Physics.