Integrated IR, visible and NIR sensor and methods of fabricating same

US5808350A · kind A · utility

Assignee

• Raytheon Company · US

Inventors

• Michael D. Jack · Goleta, US
• Michael Ray · Goleta, US
• Richard H. Wyles · Goleta, US

Key dates

• Filing date: Jan 3, 1997
• Grant date: Sep 15, 1998
• Expiry date: Jan 3, 2017

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10F39/1847
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An imaging device (10) has a plurality of unit cells that contribute to forming an image of a scene. The imaging device includes a layer of semiconductor material (16), for example silicon, that has low noise photogate charge-mode readout circuitry (20, 21, 26, 28) (e.g., CCD or CMOS readout circuitry and structures) that is disposed upon a first surface (18) of the layer. A second, opposing surface of the layer is a radiation admitting surface of the layer. The layer has a bandgap selected for absorbing electromagnetic radiation having wavelengths shorter than about one micrometer and for generating charge carriers from the absorbed radiation. The generated charge carriers are collected by the photogate charge-mode readout circuitry. A thermal sensing element (22) is disposed above and is thermally isolated from the first surface of the layer. The thermal sensing element may be, by example, one of a bolometer element, a pyroelectric element, or a thermopile element. A layer (12) of narrower bandgap semiconductor material can also be employed with this invention, wherein the layer of narrower bandgap semiconductor material (such as InGaAs or HgCdTe) is atomically bonded to the seco…