An in-situ curvature measurement equipment has been used to measure the curvature change of 4H-SiC 8degrees off-axis wafers, both with and without a CVD grown epitaxial layer, under beat treatments. The curvature of the wafer was found to increase while heating on the back-side and measuring on the front-side. This was independent whether Si- or C-face was towards the heater. The change in curvature was similar to0.05 m(-1) when ramping the temperature from R.T. up to 1300 degreesC, and was slightly more pronounced in the <11 (2) over bar0> direction compared with the <1 (1) over bar 00> direction.