Dual Buried Contact Monitor
Original Publication Date: 1983-Sep-01
Included in the Prior Art Database: 2005-Feb-07
This article describes a buried contact structure that allows one of a pair of buried contact monitor structures to be connected automatically to a single set of pads regardless of whether the buried contacts are used for the first or second polysilicon layer. This saves one set of pads. In Fig. 1, there is shown a structure which is built using the buried contact mask to etch two openings in the first gate oxide. The first polysilicon (Poly 1) layer is first deposited and etched in opening 10, and a second gate oxide 12 is allowed to cover the second opening; then the second polysilicon layer (Poly 2) is deposited over the second gate oxide 12. The metal electrode makes contact with Poly 1 through a doped region 14 in the substrate. Fig. 2 illustrates an alternative use of this mask.