Photodiode

US7141833B2 · kind B2 · utility

Assignee

• Thomson Licensing · FR

Inventors

• Ingo Hehemann · Duisburg, DE
• Armin Kemna · Duisburg, DE

Key dates

• Filing date: Nov 19, 2004
• Grant date: Nov 28, 2006
• Expiry date: May 19, 2025

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S257/927

Abstract

Apart from a semiconductor substrate and a photosensitive region in the semiconductor substrate, which comprises a space charge zone region for generating a diffusion current portion and a diffusion region for generating a diffusion current portion, a photodiode includes an insulation means in the semiconductor substrate for at least partially confining the diffusion region against an adjacent surrounding region of the semiconductor substrate. The reduction of the bandwidth of photodiodes by the smearing of the response of the photodiode by the diffusion current is alleviated by providing an insulation means in the semiconductor substrate, which confines the diffusion region against the surrounding semiconductor substrate and hereby on the one hand reduces the number of charge carriers contributing to the diffusion portion by reducing the diffusion region, in which the diffusing charge carriers are generated, and on the other hand by “sucking off” diffusing charge carriers generated in the shrunk diffusion region by the insulation means, which is why same do not contribute to the photocurrent.