Abstract: A circuit that includes: a photodiode configured to absorb photons and to generate photo-carriers from the absorbed photons; a first MOSFET transistor that includes: a first channel terminal coupled to a first terminal of the photodiode and configured to collect a portion of the photo-carriers generated by the photodiode; a second channel terminal; and a gate terminal coupled to a first control voltage source; a first readout circuit configured to output a first readout voltage; a second readout circuit configured to output a second readout voltage; and a current-steering circuit configured to steer the photo-carriers generated by the photodiode to one or both of the first readout circuit and the second readout circuit.

Abstract: A method for fabricating an image sensor array having a first group of photodiodes for detecting light at visible wavelengths a second group of photodiodes for detecting light at infrared or near-infrared wavelengths, the method including forming a germanium-silicon layer for the second group of photodiodes on a first semiconductor donor wafer; defining a first interconnect layer on the germanium-silicon layer; defining integrated circuitry for controlling pixels of the image sensor array on a semiconductor carrier wafer; defining a second interconnect layer on the semiconductor carrier wafer; bonding the first interconnect layer with the second interconnect layer; defining the pixels of an image sensor array on a second semiconductor donor wafer; defining a third interconnect layer on the image sensor array; and bonding the third interconnect layer with the germanium-silicon layer.

Abstract: An apparatus including a semiconductor substrate; an absorption layer coupled to the semiconductor substrate, the absorption layer including a photodiode region configured to absorb photons and to generate photo-carriers from the absorbed photons; one or more first switches controlled by a first control signal, the one or more first switches configured to collect at least a portion of the photo-carriers based on the first control signal; and one or more second switches controlled by a second control signal, the one or more second switches configured to collect at least a portion of the photo-carriers based on the second control signal, where the second control signal is different from the first control signal.

Abstract: Structures and techniques introduced here enable the design and fabrication of photodetectors (PDs) and/or other electronic circuits using typical semiconductor device manufacturing technologies meanwhile reducing the adverse impacts on PDs' performance. Examples of the various structures and techniques introduced here include, but not limited to, a pre-PD homogeneous wafer bonding technique, a pre-PD heterogeneous wafer bonding technique, a post-PD wafer bonding technique, their combinations, and a number of mirror equipped PD structures. With the introduced structures and techniques, it is possible to implement PDs using typical direct growth material epitaxy technology while reducing the adverse impact of the defect layer at the material interface caused by lattice mismatch.

Abstract: An optical apparatus including a semiconductor substrate; a first light absorption region supported by the semiconductor substrate, the first light absorption region including germanium and configured to absorb photons and to generate photo-carriers from the absorbed photons; a first layer supported by at least a portion of the semiconductor substrate and the first light absorption region, the first layer being different from the first light absorption region; one or more first switches controlled by a first control signal, the one or more first switches configured to collect at least a portion of the photo-carriers based on the first control signal; and one or more second switches controlled by a second control signal, the one or more second switches configured to collect at least a portion of the photo-carriers based on the second control signal, wherein the second control signal is different from the first control signal.

Abstract: A method for fabricating an optical sensor includes: forming, over a substrate, a first material layer comprising a first alloy of germanium and silicon having a first germanium composition; forming, over the first material layer, a graded material layer comprising germanium and silicon; and forming, over the graded material layer, a second material layer comprising a second alloy of germanium and silicon having a second germanium composition. The first germanium composition is lower than the second germanium composition and a germanium composition of the graded material layer is between the first germanium composition and the second germanium composition and varies along a direction perpendicular to the substrate.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for eye gesture recognition. In one aspect, a method includes obtaining an electrical signal that represents a measurement, by a photodetector, of an optical signal reflected from an eye and determining a depth map of the eye based on phase differences between the electrical signal generated by the photodetector and a reference signal. Further, the method includes determining gaze information that represents a gaze of the eye based on the depth map and providing output data representing the gaze information.

Abstract: Structures and techniques introduced here enable the design and fabrication of photodetectors (PDs) and/or other electronic circuits using typical semiconductor device manufacturing technologies meanwhile reducing the adverse impacts on PDs' performance. Examples of the various structures and techniques introduced here include, but not limited to, a pre-PD homogeneous wafer bonding technique, a pre-PD heterogeneous wafer bonding technique, a post-PD wafer bonding technique, their combinations, and a number of mirror equipped PD structures. With the introduced structures and techniques, it is possible to implement PDs using typical direct growth material epitaxy technology while reducing the adverse impact of the defect layer at the material interface caused by lattice mismatch.

Abstract: A circuit, including: a photodetector including a first readout terminal and a second readout terminal different than the first readout terminal; a first readout circuit coupled with the first readout terminal and configured to output a first readout voltage; a second readout circuit coupled with the second readout terminal and configured to output a second readout voltage; and a common-mode analog-to-digital converter (ADC) including: a first input terminal coupled with a first voltage source; a second input terminal coupled with a common-mode generator, the common-mode generator configured to receive the first readout voltage and the second readout voltage, and to generate a common-mode voltage between the first and second readout voltages; and a first output terminal configured to output a first output signal corresponding to a magnitude of a current generated by the photodetector.

Abstract: The technique introduced herein decouples the traditional relationship between bandwidth and responsivity, thereby providing a more flexible and wider photodetector design space. In certain examples of the technique introduced here, a photodetector device includes a first mirror, a second mirror, and a light absorption region positioned between the first and second reflective mirrors. For example, the first mirror can be a low-reflectivity mirror, and the second mirror can be a high-reflectivity mirror. The light absorption region is positioned to absorb incident light that is passed through the first mirror and reflected between the first and second mirrors. The first mirror can be configured to exhibit a reflectivity that causes an amount of light energy that escapes from the first mirror, after the light being reflected back by the second mirror, to be zero or near zero.

Abstract: An apparatus including a semiconductor substrate; an absorption layer coupled to the semiconductor substrate, the absorption layer including a photodiode region configured to absorb photons and to generate photo-carriers from the absorbed photons; one or more first switches controlled by a first control signal, the one or more first switches configured to collect at least a portion of the photo-carriers based on the first control signal; and one or more second switches controlled by a second control signal, the one or more second switches configured to collect at least a portion of the photo-carriers based on the second control signal, where the second control signal is different from the first control signal.

Abstract: An apparatus including a semiconductor substrate; an absorption layer coupled to the semiconductor substrate, the absorption layer including a photodiode region configured to absorb photons and to generate photo-carriers from the absorbed photons; one or more first switches controlled by a first control signal, the one or more first switches configured to collect at least a portion of the photo-carriers based on the first control signal; and one or more second switches controlled by a second control signal, the one or more second switches configured to collect at least a portion of the photo-carriers based on the second control signal, where the second control signal is different from the first control signal.

Abstract: An apparatus including a semiconductor substrate; an absorption layer coupled to the semiconductor substrate, the absorption layer including a photodiode region configured to absorb photons and to generate photo-carriers from the absorbed photons; one or more first switches controlled by a first control signal, the one or more first switches configured to collect at least a portion of the photo-carriers based on the first control signal; and one or more second switches controlled by a second control signal, the one or more second switches configured to collect at least a portion of the photo-carriers based on the second control signal, where the second control signal is different from the first control signal.

Abstract: The technique introduced herein decouples the traditional relationship between bandwidth and responsivity, thereby providing a more flexible and wider photodetector design space. In certain embodiments of the technique introduced here, a photodetector device includes a first mirror, a second mirror, and a light absorption region positioned between the first and second reflective mirrors. For example, the first mirror can be a partial mirror, and the second mirror can be a high-reflectivity mirror. The light absorption region is positioned to absorb incident light that is passed through the first mirror and reflected between the first and second mirrors. The first mirror can be configured to exhibit a reflectivity that causes an amount of light energy that escapes from the first mirror, after the light being reflected back by the second mirror, to be zero or near zero.

Abstract: A light absorption apparatus includes a substrate, a light absorption layer above the substrate on a first selected area, a silicon layer above the light absorption layer, a spacer surrounding at least part of the sidewall of the light absorption layer, an isolation layer surrounding at least part of the spacer, wherein the light absorption apparatus can achieve high bandwidth and low dark current.

Abstract: A light absorption apparatus includes a substrate, a light absorption layer above the substrate on a first selected area, a silicon layer above the light absorption layer, a spacer surrounding at least part of the sidewall of the light absorption layer, an isolation layer surrounding at least part of the spacer, wherein the light absorption apparatus can achieve high bandwidth and low dark current.

Abstract: A light absorption apparatus includes a substrate, a light absorption layer above the substrate on a first selected area, a silicon layer above the light absorption layer, a spacer surrounding at least part of the sidewall of the light absorption layer, an isolation layer surrounding at least part of the spacer, wherein the light absorption apparatus can achieve high bandwidth and low dark current.

Abstract: Examples of the various techniques introduced here include, but not limited to, a mesa height adjustment approach during shallow trench isolation formation, a transistor via first approach, and a multiple absorption layer approach. As described further below, the techniques introduced herein include a variety of aspects that can individually and/or collectively resolve or mitigate one or more traditional limitations involved with manufacturing PDs and transistors on the same substrate, such as above discussed reliability, performance, and process temperature issues.

Abstract: A semiconductor optical sensor includes a plurality of sensing units and to senses an incident optical signal to generate an electrical signal. One of the sensing units includes a substrate, an optical sensing element, a lens and an optical shielding element. The optical sensing element, whose material is different from that of the substrate, converts the incident optical signal into the electrical signal. The lens, whose material includes the same as that of the substrate, guides the incident optical signal to the optical sensing element by changing the propagation path of the incident optical signal. The optical shielding element, which surrounds the optical sensing element, alters the propagation path or propagation distance of the incident optical signal after the incident optical signal passes through the lens such that the incident optical signal will not reach an optical sensing element of an adjacent sensing unit.

Abstract: Examples of the various techniques introduced here include, but not limited to, a mesa height adjustment approach during shallow trench isolation formation, a transistor via first approach, and a multiple absorption layer approach. As described further below, the techniques introduced herein include a variety of aspects that can individually and/or collectively resolve or mitigate one or more traditional limitations involved with manufacturing PDs and transistors on the same substrate, such as above discussed reliability, performance, and process temperature issues.