Patent · US Expired

Field-effect transistor having local threshold-adjust doping

US6127700A · kind A · utility

67Cited by
16References
51Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 12, 1995
Grant dateOct 3, 2000
Priority date
Expiry dateSep 12, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D84/856

Abstract

An insulated-gate field-effect transistor utilizes local threshold-adjust doping to control the voltage at which the transistor turns on. The local threshold-adjust doping is present along part, but not all, of the lateral extent of the channel. In the transistor structure, a channel zone laterally separates a pair of source/drain zones. The channel zone is formed with a main channel portion and a more heavily doped threshold channel portion that contains the local threshold-adjust doping. Gate dielectric material vertically separates the channel zone from an overlying gate electrode. The transistor is a long device in that the gate electrode is longer, preferably at least 50% longer, than the gate electrode of a minimum-sized transistor whose gate length is approximately the minimum feature size. The long-gate transistor is suitable for use in analog and high-voltage digital portions of a VLSI circuit.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.