Abstract:
A mid-infrared detector that uses a heavily doped material (e.g., indium arsenide) as a backplane to the detector structure to improve detector performance and fabrication cost. The infrared detector includes a substrate and a backplane of heavily doped material consisting of two or more of the following materials: indium, gallium, arsenic and antimony. The backplane resides directly on the substrate. The infrared detector further includes a photodetector (e.g., type-I or type-II strained layer superlattice (SLS) nBn photodetector, type-I or type-II SLS pn junction photodetector, a quantum-dot infrared photodetector, a quantum well infrared photodetector, a homogeneous material pn junction photodetector) residing directly on the backplane. Additionally, the infrared detector may include a metal structure residing directly on the photodetector. In this manner, the absorption of electromagnetic energy in the photodetector is enhanced.
Abstract:
A semiconductor device operable to demodulate incident modulated electromagnetic radiation, the semiconductor device comprising: a pinned photodiode structure including a substrate of a first type, an implant layer of a second type disposed within the substrate, first and second auxiliary implant layers of the second type disposed within the substrate and each disposed adjacent to the implant layer of the second type, an implant layer of the first type disposed within the implant layer of the second type and extending into the first and second auxiliary implant layers of the second type, an insulator disposed on a surface of the substrate, and a photo-detection region; first and second transfer gates disposed on a surface of the insulator, the transfer gates being operable to generate a field within the substrate; and first and second floating diffusion implant layers of the second type disposed within the substrate.
Abstract:
Techniques for enhancing the quantum efficiency (QE) in photodiodes and avalanche photodiodes with the use of microstructures are described. The microstructures, such as holes, effectively increase the absorption of the photons. QE can be enhanced using heterojunction PIN structures which can result in less light absorbed in the P and/or N regions and more light absorbed in the I region. Various alloys of GeSi can be used for I and/or P regions. The microstructured holes can be funnel shaped, aperiodic, non-circular, textured and/or slanted which can further increase QE.
Abstract:
A photodetector has a photoactive layer of semiconducting inorganic nanoparticles positioned between a hole transport electron blocking layer of a first metal oxide and an electron transport hole blocking layer of a second metal oxide. The nanoparticles are responsive to electromagnetic radiation in at least the infrared region of the spectrum. The first metal oxide can be NiO, and the second metal oxide can be ZnO or TiO 2 . The metal oxide layers render the photodetector stable in air, even in the absence of an encapsulating coating around the photodetector. The photodetector has a P-I-N structure.
Abstract:
Nanomaterials having a reduced wetting layer, methods of making the nanomaterials and uses of the nanomaterials. The nanomaterials with reduced wetting layer can be used in optoelectronic devices and photovoltaic devices. The nanomaterials comprise a capping layer that results in a reduced wetting layer. The devices having a reduced wetting layer exhibit longer photoelectron lifetime that increases the responsivity and sensitivity of detectors and the conversion efficiency of photovoltaic devices.
Abstract:
The invention relates to a resonant diode having a ferromagnetic (FM) tunnel contact for generating an electric current, the amplitude of which is determined by the polarization state of the absorbed light. The invention is essentially characterized by the presence of a stack of semi-conductor layers (B1, W, B2) thus defining a carrier confinement area. The operation principle comprises generating polarized carriers, electron-hole pairs in dual-barrier quantum semi-conductor wells or boxes by the resonant absorption of a light wave having circular or elliptic polarization. The invention can be used as a basic element or in the form of a two-dimensional array as a magnetic memory element, a light polarization detector, or a magnetic field sensor.
Abstract:
A uni-travelling carrier (UTC) photodiode comprising an absorption region (22) of p-type doped material. The photodiode further comprises a first collector layer (23) and second collector layer (24) wherein the absorption region (22) is located between the first collector layer (23) and the second collector layer (24) and a contact layer (21) made of p-type material is located within the absorption region (22). By this double collector UTC structure the responsivity bandwidth trade-off is improved since the current caused by the movement of the electrons (n1,n2) generated as a result of light absorption in the absorption region (22) is directed towards two separate collectors (23, 24).
Abstract:
In at least one embodiment, an infrared (IR) sensor comprising a thermopile is provided. The thermopile comprises a substrate and an absorber. The absorber is positioned above the substrate and a gap is formed between the absorber and the substrate. The absorber receives IR from a scene and generates an electrical output indicative of a temperature of the scene. The absorber is formed of a super lattice quantum well structure such that the absorber is thermally isolated from the substrate. In another embodiment, a method for forming an infrared (IR) detector is provided. The method comprises forming a substrate and forming an absorber with a plurality of alternating first and second layers with a super lattice quantum well structure. The method further comprises positioning the absorber about the substrate such that a gap is formed to cause the absorber to be suspended about the substrate.