Infrared camera sensor

• US 9,018,723 B2
• Filed: 06/27/2013
• Issued: 04/28/2015
• Est. Priority Date: 06/27/2013
• Status: Active Grant

• Current Assignee: STMicroelectronics International N.V. (STMicroelectronics NV)
• Original Assignee: Stmicroelectronics Pte Limited (STMicroelectronics NV)
• Inventors: Le Neel, Olivier, Shankar, Ravi, Loh, Tien Choy
• Primary Examiner(s): Soward, Ida M
• Application Number:
  US13/929,610
• Publication Number:
  US 20150001659A1
• Time in Patent Office: 670 Days
• Field of Search: 257/415, 257/428, 257/431, 257/432, 257/444, 257/E31.093
• US Class Current: 257/432
• CPC Class Codes: H01L 27/14629 Reflectors
• CPC Class Codes: H01L 27/14634 Assemblies, i.e. Hybrid structures
• CPC Class Codes: H01L 27/1467 of the hybrid type
• CPC Class Codes: H01L 27/14685 Process for coatings or optical elements
• CPC Class Codes: H01L 27/1469 Assemblies, i.e. hybrid integration
• CPC Class Codes: H01L 2924/1461 MEMS

Abstract

The present disclosure is directed to an infrared sensor that includes a plurality of pairs of support structures positioned on the substrate, each pair including a first support structure adjacent to a second support structure. The sensor includes plurality of pixels, where each pixel is associated with one of the pairs of support structures. Each pixel includes a first infrared reflector layer on the substrate between the first and the second support structures, a membrane formed on the first and second support structures, a thermally conductive resistive layer on the membrane and positioned above the first infrared reflector layer, a second infrared reflector layer on the resistive layer, and an infrared absorption layer on the second infrared reflector layer.

Claims

1. A device, comprising:

a substrate;

a membrane above the substrate;

a single chamber having a plurality of integrated cavities;

a plurality of support structures between the membrane and the substrate, the support structures positioned between adjacent cavities;

an array of infrared sensor cells on the substrate, each cell positioned at boundaries between adjacent cavities, each cell including;

a first infrared reflector layer on the substrate between two of the support structures;

a thermally conductive resistive layer on the membrane and positioned above the first infrared reflector layer;

a second infrared reflector layer on the resistive layer; and

an infrared absorption layer on the resistive layer.

2. The device of claim 1 wherein the first infrared reflector layer is separated from the resistive layer by air that corresponds to one of the boundaries between two of the cavities.

3. The device of claim 1 wherein the membrane includes a plurality of openings, each opening being positioned above a central location of one of the cavities.

4. The device of claim 1 wherein each cell includes:

a first conductive layer on the membrane and configured to transmit a row signal, the resistive layer overlaps the first conductive layer above a first one and above a second one of the support structures; and

a second conductive layer on the resistive layer and configured to transmit a column signal, the second conductive layer overlaps the resistive layer and the first conductive layer above the first one and above the second one of the support structures.

5. The device of claim 4 wherein the second infrared reflector layer and the infrared absorption layer have a same surface area and are positioned between the first one of the support structures and the second one of the support structures.

6. An infrared sensor, comprising:

a substrate;

a plurality of pairs of support structures positioned on the substrate, each pair including a first support structure adjacent to a second support structure;

a plurality of pixels, each pixel associated with one of the pairs of support structures, each pixel including;

a first infrared reflector layer on the substrate between the first and the second support structures;

a membrane formed on the first and second support structures;

a thermally conductive resistive layer on the membrane and positioned above the first infrared reflector layer;

a second infrared reflector layer on the resistive layer; and

an infrared absorption layer on the second infrared reflector layer.

7. The sensor of claim 6 wherein the plurality of support structures are separated from each other by a plurality of integrated cavities that form a single chamber.

8. The sensor of claim 6 wherein each pixel further includes:

a first conductive layer formed on the membrane, between the resistive layer and the membrane; and

a second conductive layer formed on the resistive layer.

9. The sensor of claim 8 wherein the membrane, the first conductive layer, the resistive layer, and the second conductive layer are stacked above the first support structure and the second support structure.

10. The sensor of claim 9 wherein the membrane and the resistive layer extend between the first and second support structure and are suspended above the first reflective layer.