Photosensitive imaging devices and associated methods

• US 10,361,232 B2
• Filed: 06/05/2017
• Issued: 07/23/2019
• Est. Priority Date: 09/17/2009
• Status: Active Grant

• Current Assignee: SiOnyx, LLC (DC Capital Partners, LLC)
• Original Assignee: SiOnyx, LLC (DC Capital Partners, LLC)
• Inventors: Haddad, Homayoon, McKee, Jeffrey, Jiang, Jutao, Palsule, Chintamani, Forbes, Leonard
• Primary Examiner(s): Bachner, Robert G
• Application Number:
  US15/614,269
• Publication Number:
  US 20170271391A1
• Time in Patent Office: 778 Days
• CPC Class Codes: H01L 27/1461 characterised by the photosensitive area
• CPC Class Codes: H01L 27/1462 Coatings
• CPC Class Codes: H01L 27/14623 Optical shielding
• CPC Class Codes: H01L 27/14625 Optical elements or arrangements associated with the device
• CPC Class Codes: H01L 27/14629 Reflectors
• CPC Class Codes: H01L 27/1464 Back illuminated imager structures
• CPC Class Codes: H01L 27/14645 Colour imagers
• CPC Class Codes: H01L 27/14685 Process for coatings or optical elements
• CPC Class Codes: H01L 27/14689 MOS based technologies
• CPC Class Codes: H01L 31/0232 Optical elements or arrangements associated with the device H01L31/0236 takes precedence; for photovoltaic cells H01L31/054; for photovoltaic modules H02S40/20
• CPC Class Codes: H01L 31/0236 Special surface textures
• CPC Class Codes: H01L 31/0352 characterised by their shape or by the shapes, relative sizes or disposition of the semiconductor regions

Abstract

Backside illuminated photosensitive devices and associated methods are provided. In one aspect, for example, a backside-illuminated photosensitive imager device can include a semiconductor substrate having multiple doped regions forming a least one junction, a textured region coupled to the semiconductor substrate and positioned to interact with electromagnetic radiation, and a passivation region positioned between the textured region and the at least one junction. The passivation region is positioned to isolate the at least one junction from the textured region, and the semiconductor substrate and the textured region are positioned such that incoming electromagnetic radiation passes through the semiconductor substrate before contacting the textured region.

Additionally, the device includes an electrical transfer element coupled to the semiconductor substrate to transfer an electrical signal from the at least one junction.

Claims

1. A backside-illuminated photosensitive imager device, comprising:

a plurality of semiconductor devices including a semiconductor substrate having a light incident side and multiple doped regions forming at least one junction;

a first textured region associated with the semiconductor substrate and positioned to interact with electromagnetic radiation so as to cause at least a portion of said electromagnetic radiation to experience multiple passes within said semiconductor substrate so as to enhance quantum efficiency of said imager device, wherein the first textured region is positioned such that incoming electromagnetic radiation passes through the semiconductor substrate before contacting the textured region;

a second textured region associated with the light incident side of the semiconductor substrate, wherein the at least one junction is disposed between the first and second textured regions; and

at least one isolation feature operable to isolate the plurality of semiconductor devices from each other.

2. The device of claim 1, wherein the at least one isolation feature is operable to electrically isolate the plurality of semiconductor devices from each other.

3. The device of claim 1, wherein the at least one isolation feature is operable to optically isolate the plurality of semiconductor devices from each other.

4. The device of claim 1, wherein the at least one isolation feature is a deep trench isolation feature.

5. The device of claim 1, wherein the at least one isolation feature is a shallow trench isolation feature.

6. The device of claim 1, wherein the at least one isolation feature includes a material selected from the group consisting of, metals, oxides, polymers, or combinations thereof.

7. The device of claim 1, wherein the at least one isolation feature includes a reflecting material.

8. The device of claim 1, further comprising a reflective layer coupled to the semiconductor substrate and positioned to interact with electromagnetic radiation.

9. The device of claim 8, wherein the reflective layer includes a material selected from the group consisting of metal, oxide, or combinations thereof.

10. The device of claim 8, wherein the reflective layer is a Bragg reflector.

11. The device of claim 1, wherein the semiconductor substrates are epitaxially grown.

12. The device of claim 1, further comprising at least on electrical transfer element functionally coupled to the plurality of semiconductor devices.

13. The device of claim 1, wherein the semiconductor substrates are comprised of silicon.

14. The device of claim 1, wherein the textured region is formed by a technique selected from the group consisting of lasing, chemical etching, anisotropic etching, isotropic etching, nanoimprinting, additional material deposition, and combinations thereof.

15. The device of claim 1, further comprising a passivation region positioned between the first textured region and the at least one junction.

16. The device of claim 15, wherein the passivation region is coupled directly to the at least one junction.

17. The device of claim 1, wherein the first textured region is coupled directly to the substrate adjacent the at least one junction.