Patent Number: 046802436
Section: abstract

A method for manufacturing a mask (100) for use in x-ray photolithographic processes includes the step of coating a silicon wafer (10) with a layer of boron nitride (12). A masking substance (14) is used to coat one side of the boron nitride coated wafer, and the boron nitride is etched off of the other side of the wafer. The wafer (10) is then bonded to a pyrex ring (16) using a field assisted thermal bonding process. During the field assisted thermal bonding process, the silicon (11) is bonded directly to the pyrex (16). Then, a zirconium layer (24) is used to cover the mask and is selectively etched where it is desired to remove a circular portion of the silicon. Thereafter the silicon is subjected to a semianisotropic etch. The remaining structure includes a pyrex ring bonded to a silicon ring across which a layer of boron nitride is stretched. The layer of boron nitride is subjected to an annealing process and is then coated with an x-ray opaque material.