Integrated Avalanche Photodiode arrays

• US 9,627,569 B2
• Filed: 05/21/2015
• Issued: 04/18/2017
• Est. Priority Date: 04/19/2013
• Status: Active Grant

• Current Assignee: Lightspin Technologies Inc.
• Original Assignee: Lightspin Technologies Inc.
• Inventors: Harmon, Eric S.
• Primary Examiner(s): Pham, Long
• Application Number:
  US14/718,352
• Publication Number:
  US 20150270430A1
• Time in Patent Office: 698 Days
• CPC Class Codes: H01L 27/1446 in a repetitive configuration
• CPC Class Codes: H01L 27/14609 Pixel-elements with integrated switching, control, storage or amplification elements scanning details of imagers (circuitry of solid-state image sensors H04N25/00); circuitry of imagers H04N25/70
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers
• CPC Class Codes: H01L 27/14683 Processes or apparatus peculiar to the manufacture or treatment of these devices or parts thereof not peculiar thereto H01L21/00
• CPC Class Codes: H01L 31/0352 characterised by their shape or by the shapes, relative sizes or disposition of the semiconductor regions
• CPC Class Codes: H01L 31/107 the potential barrier working in avalanche mode, e.g. avalanche photodiodes
• CPC Class Codes: H01L 31/1844 comprising ternary or quaternary compounds, e.g. Ga Al As, In Ga As P
• CPC Class Codes: Y02E 10/544 Solar cells from Group III-V materials
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

The present disclosure includes devices for detecting photons, including avalanche photon detectors, arrays of such detectors, and circuits including such arrays. In some aspects, the detectors and arrays include a virtual beveled edge mesa structure surrounded by resistive material damaged by ion implantation and having side wall profiles that taper inwardly towards the top of the mesa structures, or towards the direction from which the ion implantation occurred. Other aspects are directed to masking and multiple implantation and/or annealing steps. Furthermore, methods for fabricating and using such devices, circuits and arrays are disclosed.

Claims

1. A photo detector array, comprising:

a substrate layer;

a plurality of doped semiconductor layers including a first semiconductor layer doped with a first dopant disposed above said substrate and a second semiconductor layer doped with a second dopant disposed above said first semiconductor layer and proximal thereto;

said first and second semiconductor layers being ion implanted in a plurality of selected regions thereof at generally positive lateral profile angles with respect to a normal to said first and second semiconductor layers so as to form a corresponding plurality of mesa structures having angled side profiles in said first and second semiconductor layers; and

a photon detection circuit including a plurality of ohmic connections to one or more of said mesa structures so as to provide at least one output signal of said array corresponding to one or more detected photon interactions within said mesa structures.

2. The array of claim 1, said photon detection circuit comprising a passive quench circuit.

3. The array of claim 1, each of said mesa structures separated from the others in said array by an ion implanted isolation region.

4. The array of claim 1, said plurality of virtual mesa structures having a common surrounding electrically isolating region formed around the same by one or more ion implantation processes.

5. The array of claim 4, said common surrounding electrically isolating region having a first thickness, resulting from a first ion implantation process, and a second thickness of said plurality of selected ion implanted regions, resulting from a second ion implantation process, that define said virtual mesa structures.

6. The array of claim 5, said second ion implantation density being greater than said first ion implantation density.

7. The array of claim 1, at least a portion of one of said first and second semiconductor layers having a graded density doping profile as a function of its thickness.