To apply our grayscale process to the realization of functional devices, we considered the material in which the device was to be fabricated, and began with the height profile for the device that we wished to produce in this material. If the device material is other than photoresist, it is necessary to transfer the device profile from the resist into the desired material via etching. For a grayscale process, the photoresist etch mask must be removed in a smooth and controllable fashion, so that the underlying material is gradually exposed and etched. The result is a translation.
