Patent ID: 6764867
Filing Date: 2004-07-20
Classification: H01L

Abstract:
A method of detecting a reticle option layer in an integrated circuit device comprising:measuring the current through a first MOS transistor in an integrated circuit device by forcing a test voltage on the drain and the gate wherein said gate and said drain of said first MOS transistor are connected together, wherein the source of said first MOS transistor is connected to a reference voltage, and wherein said first MOS transistor is not parametrically affected by a reticle option layer; measuring the current through a second MOS transistor in said integrated circuit device by forcing same said test voltage on the drain and the gate wherein said gate and said drain of said second MOS transistor are connected together, wherein the source of said second MOS transistor is connected to a reference voltage, and wherein said second MOS transistor is parametrically affected by said reticle option layer; and comparing said current through said first MOS transistor and said current through said second MOS transistor to detect the presence of said reticle option layer in said integrated circuit device.