Process and product for making a single supply N-channel silicon gate device

摘要

A process is described wherein an N-channel silicon gate device operates from a single voltage supply. This process includes an ion implantation step into the gate region of both the load and switch devices for adjusting upwards the threshold voltage of such N-channel silicon gate load and switch devices. This ion implantation of the gate region utilizes the dosage and ion implant energy as factors in determining the change in the threshold voltage. The ion implantation is in a region essentially at the surface of the gate region and as such appears to be a change in the Qss term of the device. The effect of the ion implantation is to increase upwards the threshold voltage of the structure as compared with the expected threshold voltage based on the resistivity level of the starting material of the wafer. The overall effect of this process is to provide an active device having a higher output voltage than can be expected from using the starting resistivity material. The output voltage is approximately 25% greater using this process because the body effect turns out to be much lower in the present process than in the prior art process.