A Comprehensive Characterization of Stress Relaxed ZnO …
499
Fig. 1 a–e Film stress mapping profile of ZnO thin film for varying oxygen content
are reduced as well as stoichiometry of ZnO thin films is not balanced which again
causes in-plane stress. Therefore, optimal process conditions are desired for good
quality stress relaxed ZnO thin films. As discussed, wafer curvature changes with
R O2 according to Eq. (1) and Fig. 2 shows the accumulated wafer curvature due to
SiO 2 and ZnO layer depositions. The SiO 2 film showed nearly similar compressive
stress (~− 1.6 × 10
9 dyne/cm
2 ) in all the wafers. Successively, ZnO layers (~0.8 μm)
were grown and accumulated curvature is shown in Fig. 2. It is found that 30% R O2
499
Fig. 1 a–e Film stress mapping profile of ZnO thin film for varying oxygen content
are reduced as well as stoichiometry of ZnO thin films is not balanced which again
causes in-plane stress. Therefore, optimal process conditions are desired for good
quality stress relaxed ZnO thin films. As discussed, wafer curvature changes with
R O2 according to Eq. (1) and Fig. 2 shows the accumulated wafer curvature due to
SiO 2 and ZnO layer depositions. The SiO 2 film showed nearly similar compressive
stress (~− 1.6 × 10
9 dyne/cm
2 ) in all the wafers. Successively, ZnO layers (~0.8 μm)
were grown and accumulated curvature is shown in Fig. 2. It is found that 30% R O2