Charge-coupled device with lowering of transfer potential at output and fabrication method thereof

US4873562A · kind A · utility

Assignee

• Thomson-CSF · FR

Inventors

• Yvon Cazaux · Grenoble, FR
• Yves Thenoz · Grenoble, FR
• Didier Herault · Grenoble, FR
• Pierre Blanchard · Échirolles, FR

Key dates

• Filing date: Dec 21, 1988
• Grant date: Oct 10, 1989
• Expiry date: Dec 21, 2008

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D44/464

Abstract

Disclosed are a charge-coupled device with lowering of output potential as well as a method for the fabrication of this device. In a known way, the device comprises, upstream on a semiconducting substrate with a first type of doping (P), a semiconducting layer with a second type of doping (N) and an insulating layer covering the former layer. Pairs of electrodes are formed on the insulating layer. Each pair has a transfer electrode and a storage electrode. Zones with a third type of doping N.sup.+) are made in the layer of a second type (N). A layer with a third type of doping (N.sup.-) is made downstream, in the layer with a second type of doping, and, downstream, there is formed at least one other pair of additional transfer and storage electrodes. A zone with a fourth type of doping (N.sup.--) is made beneath the additional transfer electrode in the layer with a third type of doping (N.sup.-). This pair of additional electrodes and the zone with a fourth type of doping make it possible to obtain the lowering of transfer potential at output.