METHODS FOR FORMING FINFETS HAVING A CAPPING LAYER FOR REDUCING PUNCH THROUGH LEAKAGE

摘要

A method for forming FinFETs having a capping layer for reducing punch through leakage includes providing an intermediate semiconductor structure having a semiconductor substrate and a fin disposed on the semiconductor substrate. A capping layer is disposed over the fin, and an isolation fill is disposed over the capping layer. A portion of the isolation fill and the capping layer is removed to expose an upper surface portion of the fin. Tapping layer and a lower portion of the fin define an interface dipole layer barrier, a portion of the capping layer operable to provide an increased negative charge or an increased positive charge adjacent to the fin, to reduce punch-through leakage compared to a fin without the capping layer.

主权项

1. A method comprising:
providing an intermediate semiconductor structure comprising:
a semiconductor substrate;a fin disposed on the semiconductor substrate; providing a first capping layer disposed over the fin; providing first isolation fill disposed over the capping layer; removing a portion of the first isolation fill and the first capping layer to expose an upper surface portion of the fin; providing a second capping layer disposed over the exposed fin, and a second isolation fill over the second capping layer, the second capping layer being different from the first capping layer; removing a portion of the second capping layer and second isolation fill to expose an upper surface of the fin; and wherein the capping layers and a lower portion of the fin define an interface dipole layer barrier, a portion of the capping layers operable to provide an increased negative charge or an increased positive charge adjacent to the fin, to reduce punch-through leakage compared to a fin without the capping layers.