Method of making self-aligned, high-enegry implanted photodiode for solid-state image sensors
US6306676A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 4, 1996 |
| Grant date | Oct 23, 2001 |
| Priority date | — |
| Expiry date | Apr 4, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F39/1534
Abstract
A method and apparatus of making high energy implanted photodiode that is self aligned with the transfer gate, the high energy implant is defined by providing a substrate, or well, of a first conductivity type, defining a charge coupled device within the substrate, or well, such that gate electrode layers are allowed to exist over areas to contain photodiodes during construction of the charge coupled device, patterning a masking layer to block high energy implants such that openings in the masking layer are formed over the areas of the photodiodes, anisotropically etching down through the gate electrode over the photodiodes to the gate dielectric material, implanting photodiodes with high-energy ions of a second conductivity type opposite the first conductivity type and creating a pinned photodiode by employing a shallow implant of the first conductivity type. The apparatus made by this method yields a photodiode employing high energy ions to form the P/N junction that is self aligned with the transfer gate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.