Patent ID: 7897260

Claim:
A coated article including a coating supported by a glass substrate, the coating comprising from the glass substrate outwardly: a first IR reflecting layer comprising silver; a first dielectric stack located between the first IR reflecting layer comprising silver and the glass substrate; a second IR reflecting layer comprising silver; a second dielectric stack located between the first and second IR reflecting layers; a third dielectric stack located above the first and second IR reflecting layers; wherein the second dielectric stack comprises first and second tin oxide-based layers, spaced apart by at least a layer comprising silicon nitride; wherein the first dielectric stack has no tin oxide-based layers, and the third dielectric stack has only one tin oxide-based layer; and wherein the coated article is capable of being heat treated for 18 minutes at a furnace temperature of about 650 degrees C. without realizing a visible transmission decrease of more than 1% from the 8 minute mark to the 18 minute mark of such heat treatment, measured monolithically.