Low capacitance optoelectronic device

US9917419B2 · kind B2 · utility

Assignee

• VI SYSTEMS GmbH · DE

Inventors

• Joerg-Reinhardt Kropp · Berlin, DE
• Nikolay Ledentsov · Berlin, DE
• Vitaly Shchukin · Berlin, DE

Key dates

• Filing date: Jun 26, 2016
• Grant date: Mar 13, 2018
• Expiry date: Jun 26, 2036

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01S2301/176
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An optoelectronic semiconductor device is disclosed wherein the device is a vertical-cavity surface-emitting laser or a photodiode containing a section, the top part of which is electrically isolated from the rest of the device. The electric isolation can be realized by etching a set of holes and selective oxidation of AlGaAs layer or layers such that the oxide forms a continuous layer or layers everywhere beneath the top surface of this section. Alternatively, a device can be grown epitaxially on a semi-insulating substrate, and a round trench around a section of the device can be etched down to the semi-insulating substrate thus isolating this section electrically from the rest of the device. Then if top contact pads are deposited on top of the electrically isolated section, the pads have a low capacitance, and a pad capacitance below two hundred femto-Farads, and the total capacitance of the device below three hundred femto-Farads can be reached.