Method of forming improved contacts from polysilicon to silicon or other polysilicon layers

摘要

The method of the present invention introduces a method of forming conductively doped contacts on a supporting substrate in a semiconductor device that minimizes the lateral out-diffusion of the conductive dopants and also provides for a low resistive contact by the steps of: preparing a conductive area to accept contact formation; forming a phosphorus insitu doped polysilicon layer over the conductive area; forming an arsenic insitu doped polysilicon layer over the phosphorus insitu doped polysilicon layer, wherein the two insitu doped polysilicon layers are deposited one after another in separate deposition steps; and annealing the layers at a temperature range of approximately 900 DEG -1100 DEG C. thereby, resulting in sufficient thermal treatment to allow phosphorus atoms to break up a first interfacial silicon dioxide layer formed between the conductive area and the phosphorus insitu doped polysilicon layer.