Method for shielding polysilicon resistors from hydrogen intrusion

摘要

A polysilicon resistor structure and a method by which the polysilicon resistor structure may be formed. A polysilicon resistor is formed upon the surface of a semiconductor substrate. A pair of dummy polysilicon layers is formed along opposite edges and separated from the polysilicon resistor. A pair of metal sidewalls is then formed upon the upper surfaces of the pair of dummy polysilicon layers, and a top metal layer is formed bridging the upper surfaces of the pair of metal sidewalls. The pair of dummy polysilicon layers, the pair of metal sidewalls and the top metal layer form an open ended cavity upon the semiconductor substrate within which structure the polysilicon resistor resides. The polysilicon resistor is separated from the structure by an insulating material which is not susceptible to outgassing of hydrogen.