Patent ID: 11840034

Abstract:
Methods are disclosed for fabricating molds for forming eyepieces having waveguides with integrated spacers. The molds are formed by etching deep holes (e.g., 5 μm to 1000 μm deep) into a substrate using a wet etch or dry etch. The etch masks for defining the holes may be formed with a thick metal layer and/or multiple layers of different metals. A resist layer may be disposed over the etch mask. The resist layer may be patterned to form a pattern of holes, the pattern may be transferred to the etch mask, and the etch mask may be used to transfer the pattern into the underlying substrate. The patterned substrate may be utilized as a mold onto which a flowable polymer may be introduced and allowed to harden. Hardened polymer in the holes may form integrated spacers. The hardened polymer may be removed from the mold to form a waveguide with integrated spacers.