Method for manufacturing memories with thin film transistors

Abstract

Abstract A method for manufacturing a TFT type memory providing steps of (i) depositing a first insulating layer over a semiconductor substrate having a polysilicon gate formed by a first polysilicon film, and then opening a first contact hole so as to form a first insulating film, (ii) depositing a second polysilicon layer over the semiconductor substrate including the first contact hole, and then patterning the same so as to form a second polysilicon film, (iii) depositing a second insulating film over the semiconductor substrate including the second polysilicon film, and then opening a second contact hole so as to form a second insulating film, (iv) depositing a third polysilicon layer over the semiconductor substrate including the second contact hole, and then patterning the same so as to form a third polysilicon film as a capacitor bottom electrode, (v) implanting ions in the second polysilicon film in a region other than a capacitor formation region so as to form a source/drain region, (vi) depositing a third insulating layer over the whole surface, and then opening a contact window so as to form a third insulating film as a capacitor insulating film, and (vii) depositing a fourth polysilicon layer over the semiconductor substrate including the contact window, and then patterning the same so as to make a fourth polysilicon film remain as a capacitor top electrode in only the capacitor formation region.

Inventors

• 👤 Alberto Oscar Adan

Bibliographic Details