Patent ID: 6511889
Filing Date: 2003-01-28
Classification: H01L

Abstract:
A method of fabricating a reference voltage supply circuit, said reference supply circuit having:a first conductive type semiconductor substrate; a bipolar transistor having a second conductive type well for a base formed at the surface of said semiconductor substrate; and a resistor element connected to an emitter of said bipolar transistor and having a second conductive type well for a resistor at the surface of said semiconductor substrate wherein said resistor element comprises a first conductive type diffused layer for bias formed between second conductive diffused layers each of the second conductive diffused layers functioning as a resistor electrode, an operational amplifier with at least one input connected to the resistor electrode, and an output providing a reference voltage; said method comprising the step of fabricating said well for a resistor and said well for a base at the same time.