Multi-wavelength band infrared detector

• US 4,948,976 A
• Filed: 02/09/1989
• Issued: 08/14/1990
• Est. Priority Date: 02/09/1989
• Status: Expired due to Fees

• Current Assignee: Business Alliance Capital Corp. (Banco Santander SA)
• Original Assignee: Servo Corporation of America
• Inventors: Baliga, Shankar B., Rost, Martin R., Little, John A., Jain, Adishwar L.
• Primary Examiner(s): FIELDS, CAROLYN
• Application Number:
  US07/308,409
• Time in Patent Office: 551 Days
• Field of Search: 250/339, 250/370.06, 250/226, 250/349, 250/338.1, 250/338.4
• US Class Current: 250/370.06
• CPC Class Codes: H01L 25/043 Stacked arrangements of devices
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 31/0324 comprising only AIVBVI or AIIBIVCVI chalcogenide compounds, e.g. Pb Sn Te
• CPC Class Codes: H01L 31/09 Devices sensitive to infrared, visible or ultraviolet radiation H01L31/101 takes precedence

Abstract

An infrared detector capable of obtaining coincident fields of view of infrared radiation of different wavelengths is provided. The detector comprises a sandwich-type construction including PbSe and PbS photoconductive film layers.

Claims

1. An infrared detector comprising a first thin film detector layer of PbSe responsive to infrared radiation in a first wavelength band, a second thin film detector layer of PbS overlying said first detector layer and responsive to infrared radiation in a second wavelength band and transparent to infrared radiation in said first wavelength band and contacts connected to each of said detector layers.

2. The invention in accordance with claim 1 further comprising a layer of arsenic triselenide immediately overlying said PbSe layer.

3. The invention in accordance with claim 2 further comprising a transmissive glass layer immediately overlying said arsenic triselenide layer, said glass layer having a refractive index matched to that of said arsenic triselenide layer.

4. The invention in accordance with claim 3 wherein said transmissive glass layer is formed of silicon monoxide.

5. The invention in accordance with claim 3 wherein said transmissive glass layer forms a substrate for said PbS film.

6. The invention in accordance with claim 1 further comprising a sealing layer overlying said PbS layer.

7. The invention in accordance with claim 6 wherein said sealing layer comprises arsenic trisulfide.