L3 Cincinnati Electronics Corporation

L-3 Communications Cincinnati Electronics Corporation

L3harris Cincinnati Electronics Corporation

Darrel Endres

Michael J Garter

Yajun Wei

Robert Jones

Steven C Allen

David Forrai

Mark Greiner

Nansheng Tang

Daniel Chmielewski

Joseph Meiners

Charles B Martin

Richard Rawe

A direct bonding method for infrared focal plane arrays, includes steps of depositing a thin adhesion layer on infrared radiation detecting material, removing a portion of the thin adhesion layer with a chemical-mechanical polishing process, forming a bonding layer at a bonding interface, and bonding the infrared radiation detecting material to a silicon wafer with the thin adhesion layer as a bonding layer. The thin adhesion layer may include SiO, where x ranges between 1.0 and 2.0. The thickness of the thin adhesion layer to form the bonding layer is 500 angstrom or less.

Infrared detector having a directly bonded silicon substrate present on top thereof

Multicolor, stacked detector devices, focal plane arrays including multicolor, stacked detector devices, and methods of fabricating the same are disclosed. In one embodiment, a stacked multicolor detector device includes a first detector and a second detector. The first detector includes a first detector structure and a first ground plane adjacent the first detector structure. The second detector includes a second detector structure and a second ground plane adjacent the second detector structure. At least one of the first ground plane and the second ground plane is transmissive to radiation in a predetermined spectral band. The first detector and the second detector are in a stacked relationship.

Mechanically stacked multicolor focal plane arrays and detection devices

Methods of fabricating multicolor, stacked detector devices and focal plane arrays are disclosed. In one embodiment, a method of fabricating a stacked multicolor device includes forming a first detector by depositing a first detector structure on a first detector substrate, and depositing a first ground plane on the first detector structure, wherein the first ground plane is transmissive to radiation in a predetermined spectral band. The method further includes bonding an optical carrier wafer to the first ground plane, removing the first detector substrate, and forming a second detector. The second detector is formed by depositing a second detector structure on a second detector substrate, and depositing a second ground plane on the second detector structure. The method further includes depositing a dielectric layer on one of the first detector structure and the second ground plane, bonding the first detector to the second detector, and removing the second detector substrate.

Methods for fabricating mechanically stacked multicolor focal plane arrays and detection devices

Focal plane arrays and infrared detector device having a transparent common ground structure and methods of their fabrication are disclosed. In one embodiment, a front-side illuminated infrared detector device includes a contact layer and a detector structure adjacent to the contact layer. The detector structure is capable of absorbing radiation. The front-side illuminated infrared detector device further includes a common ground structure adjacent the detector structure, wherein the common ground structure is transmissive to radiation having a wavelength in a predetermined spectral band, and the common ground structure has a bandgap that is wider than a bandgap of the detector structure. The front-side illuminated infrared detector device further includes an optical layer adjacent the common ground structure.

Infrared detector devices and focal plane arrays having a transparent common ground structure and methods of fabricating the same

A method of fabricating a frontside-illuminated inverted quantum well infrared photodetector may include providing a quantum well wafer having a bulk substrate layer and a quantum material layer, wherein the quantum material layer includes a plurality of alternating quantum well layers and barrier layers epitaxially grown on the bulk substrate layer. The method further includes applying at least one frontside common electrical contact to a frontside of the quantum well wafer, bonding a transparent substrate to the frontside of the quantum well wafer, thinning the bulk substrate layer of the quantum well wafer, and etching the quantum material layer to form quantum well facets that define at least one pyramidal quantum well stack. A backside electrical contact may be applied to the pyramidal quantum well stack. In one embodiment, a plurality of quantum well stacks is bonded to a read-out integrated circuit of a focal plane array.

Frontside-illuminated inverted quantum well infrared photodetector devices

Frontside-illuminated inverted quantum well infrared photodetector devices and methods of fabricating the same

According to one embodiment, an infrared focal plane comprises an array of pixels configured to detect optical radiation in a predetermined radiation band are positioned on a support substrate. The pixels are connected to pixel contacts on a read-out integrated circuit via pixel interconnects comprising bonding bumps. According to some embodiments, indium migration is blocked by a patterned electrical insulator comprising a plurality of intersecting walls defining a plurality of cells that surround each pixel interconnect. The patterned electrical insulator may be dimensioned such that it does not physically contact the support substrate, the array of pixels or pixel interconnects. In this manner, pixel-pair defects due to indium migration resulting from cryogenic thermal-cycling may be prevented, thereby extending the thermal-cycling lifetime of the focal plane array.

Growing community of inventors

West Chester, OH, United States of America

Darrel Endres