Glass wafers for semiconductor fabrication processes and methods of making same
The present disclosure is directed to the use of glass wafers as carriers, interposers, or in other selected applications in which electronic circuitry or operative elements, such as transistors, are formed in the creation of electronic devices. The glass wafers generally include a glass having a coefficient of thermal expansion equal to or substantially equal to a coefficient of thermal expansion of semiconductor silicon, an indexing feature, and a coating on at least a portion of one face of the glass.
1. A glass wafer for use in semiconductor fabrication equipment to produce electronic circuit elements, the glass wafer comprising:
a glass having a coefficient of thermal expansion from about 2×10 −6 /° C. to about 9×10 −6 /° C.;
an indexing feature configured to be recognized by the semiconductor fabrication equipment; and
a coating on at least a portion of one face of the glass, wherein the coating extends inward from an outer edge of the glass, wherein the coating changes an optical characteristic of at least a portion of the one face of the glass or changes a dielectric property of the glass, and wherein the coating is an organic polymer, a black permanent marker ink, a heat treated thin organic layer, a carbon-filled photoresist material, a darkened (cured) spin-on photoresist, a carbon-filled spin-on-glass material, an inkjetted carbon based ink, silicon nanoparticles, a sintered black screen-printed glass frit material, or a photoluminescent material.
2. The glass wafer according to claim 1 , where the coating is an opaque coating that extends inward from the outer edge of the glass for a distance of about 5 millimeters to about 20 millimeters.
3. The glass wafer according to claim 1 , wherein the coating covers all of the one face of the glass.
4. The glass wafer according to claim 1 , wherein the change in the dielectric property of the glass is effective to make the glass wafer suitable for use with electrostatic chucks.
5. The glass wafer according to claim 1 , wherein the coating is formed from an organic polymer that modifies the optical characteristic of the glass.
6. The glass wafer according to claim 1 , wherein the coating comprises a black permanent marker ink, a heat treated thin organic layer, a carbon-filled photoresist material, a darkened (cured) spin-on photoresist, a carbon-filled spin-on-glass material, or an inkjetted carbon based ink.
7. The glass wafer according to claim 1 , wherein the coating comprises silicon nanoparticles, a sintered black screen-printed glass frit material, or a photoluminescent material.