One-dimensional CCD sensor with overflow arrangement

US4236168A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventor

• Heiner Herbst · Haar, DE

Key dates

• Filing date: Feb 26, 1979
• Grant date: Nov 25, 1980
• Expiry date: Feb 26, 1999

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10F39/158

Abstract

A linear row of MIS capacitors as sensor elements are arranged on a doped semiconductor body. The MIS capacitors are separated in the semiconductor body by a potential threshold for the optically generated minority carriers. The potential threshold, for example, can be generated by means of a field shield electrode. By means of transfer gates the sensor elements are alternately coupled with CCD shift registers. An oppositely doped overflow drain which is contacted with an overflow electrode connects to the narrow side of each sensor element which is opposite the corresponding transfer gate. Each overflow drain is separated from the sensor elements by a potential threshold for the minority carriers which is smaller than the potential threshold between the sensor elements themselves. A varying thickness of the oxide layer, a varying doping and/or parts of the field shield electrode can serve for adjusting the potential threshold. In this manner, in a sensor of high component density for the electronic image gathering, an overflow arrangement is incorporated without any additional space requirement.