METHOD FOR REALIZING A CONTACT OF AN INTEGRATED WELL IN A SEMICONDUCTOR SUBSTRATE, IN PARTICULAR FOR A BASE TERMINAL OF A BIPOLAR TRANSISTOR, WITH ENHANCEMENT OF THE TRANSISTOR PERFORMANCES

摘要

A method realizes a contact of a first well of a first type of dopant integrated in a semiconductor substrate next to a second well of a second type of dopant and forming with it a parasitic diode. The method comprises: formation of the first well; formation of the second well next to the first well; definition of an oxide layer above the first and second wells; and formation of an electric contact layer above the oxide layer in correspondence with the first well for realizing an electric contact with it. The definition step of the oxide layer further comprises a deposition step of this oxide layer above the whole first well and a removal step of at least one portion of the oxide layer in correspondence with a contact area of the first well so that the contact area has a shorter length than a length of the first well.