摘要 |
A process for fabricating an optical membrane from polycrystalline silicon comprises first forming a sacrificial layer (110) on a handle wafer (100). Concavities (127) are etched into the sacrificial layer (110). Polycrystalline silicon membrane layer (125) is then formed on the sacrificial layer (110). The polycrystalline membrane layer (125) is subsequently polished to achieve the predetermined membrane thickness and surface smoothness, annealed, and then patterned. Finally, the sacrificial layer (110) is removed to release the membrane (125). The concavities (127) in the sacrificial layer (110) yield convexities in the polysilicon layer (125) to prevent stiction adhesion to the handle wafer (100). During processing, a mask used to pattern the membrane layer functions to protect a highly reflecting (HR) coating for the membrane. |