ITLDD transistor having variable work function and method for fabricating the same
US5061647A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 12, 1990 |
| Grant date | Oct 29, 1991 |
| Priority date | — |
| Expiry date | Oct 12, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/671
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A semiconductor device and process wherein an ITLDD device (60) is formed having an inverse-T (IT) transistor gate with a variable work function (.PHI.) across the gate. The variable work function is attained by depositing a work function adjusting layer onto the thin gate extensions of the IT-gate. In accordance with one embodiment of the invention, a semiconductor substrate (10) of a first conductivity type is provided having a gate dielectric layer (12) formed thereon. First and second lightly doped regions (36, 37) of a second conductivity type are formed in the substrate which are spaced apart by a channel region (38). An IT-gate electrode (48) is formed on the gate dielectric layer overlying the first and second lightly doped regions and the channel region. The IT-gate has a relatively thick central section (32) and relatively thin lateral extensions (50) projecting from the central portion along the gate dielectric layer. A work function adjusting layer (46) overlies and is in intimate contact with at least the lateral extensions of the IT-gate. The presence of the work function adjusting layer changes the electrical characteristics of the extensions relative to the central …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.