Patent ID: 6346468
Filing Date: 2002-02-12
Classification: H01L

Abstract:
An in-situ method for forming an L-shaped spacer using disposable polysilicon top spacers, comprising the steps of:a. providing a semiconductor structure having a gate structure thereon; b. implanting impurity ions to form lightly doped source and drain regions; c. forming a liner oxide layer on said gate structures; d. forming a dielectric spacer layer on said liner oxide layer; said dielectric spacer layer comprising silicon nitride; e. forming a disposable polysilicon top spacer layer on said dielectric spacer layer; f. anisotropically etching said disposable polysilicon top spacer layer to form disposable polysilicon top spacers; g. in-situ, anisotropically etching said dielectric spacer layer to form L-shaped dielectric spacers, using said disposable polysilicon top spacers as an etch mask; and h. in-situ, removing said disposable polysilicon top spacers.