A method of manufacture comprises a mask process correction (MPC) and verifying MPC accuracy. MPC may be performed on mask tape-out (MTO) data describing a mask pattern to obtain mask process corrected data. MPC may be performed to address a deviation between the MTO data and a mask to be manufactured. Verification of the MPC may be performed by generating a two-dimensional (2D) contour of mask pattern elements based on the mask process corrected data. When MPC has been verified, the mask process corrected data may be used to manufacture a mask and a semiconductor device.