Counter pocket implant to improve analog gain

摘要

A method for improving analog gain in long channel devices associated with a semiconductor workpiece is provided. A gate oxide layer is formed on the semiconductor workpiece, and a plurality of gate structures are formed over the gate oxide layer, wherein a first pair of the plurality of gate structures define a short channel device region and a second pair of the plurality of gate structures define a long channel device region. A first ion implantation with a first dopant is performed at a first angle, wherein the first dopant is one of an n-type dopant and a p-type dopant. A second ion implantation with a second dopant is performed at a second angle, wherein the second angle is greater than the first angle. The second dopant is one or an n-type dopant and a p-type dopant that is opposite of the first dopant, and a height of the plurality of gate structures and the second angle generally prevents the second ion implantation from implanting ions into the short channel device region.

主权项

1. A method for forming a semiconductor device, the method comprising:
forming a gate oxide layer on a semiconductor workpiece; forming a plurality of gate structures over the gate oxide layer, wherein the plurality of gate structures extend a predetermined height from the gate oxide layer and generally define a short channel device region and a long channel device region; performing a first ion implantation with a first dopant at a first angle when viewed from an axis perpendicular to a surface of the semiconductor workpiece, wherein the first dopant is one of an n-type dopant and a p-type dopant; and performing a second ion implantation with a second dopant at a second angle when viewed from the axis perpendicular to the surface of the semiconductor workpiece, wherein the second angle is greater than the first angle, wherein the second dopant is one of an n-type dopant and a p-type dopant that is opposite of the first dopant, and wherein the plurality of gate structures and the second angle generally prevent the second ion implantation from implanting ions into the short channel device region while generally permitting the second ion implantation to implant ions into the long channel device region.