Abstract: An imaging device may include single-photon avalanche diodes (SPADs). The single-photon avalanche diodes may be arranged in a one-dimensional or two-dimensional array in a SPAD-based semiconductor device. The SPAD-based semiconductor device may also include a transparent cover glass that is formed over the array of SPADs. Each line of SPADs within the SPAD-based semiconductor device may be covered by a respective light spreading lens. The light spreading lens may be formed as a groove in an upper surface of the transparent cover glass. The light spreading lens may have a uniform cross-section along its length. The light spreading lens may be formed as a convex lens on an upper or lower surface of the transparent cover glass.

Abstract: A semiconductor package may include a line array of single-photon avalanche diodes (SPADs). The line array of single-photon avalanche diodes may be split between multiple silicon dice. Each silicon die may be overlapped by at least one lens to focus light away from gaps between the dice and towards the single-photon avalanche diodes. There may be one single-photon avalanche diode for each silicon die or multiple single-photon avalanche diodes for each silicon die. When there are multiple single-photon avalanche diodes for each silicon die, lenses may be formed over only the edge single-photon avalanche diodes.

Abstract: An imaging device may include single-photon avalanche diodes (SPADs). The single-photon avalanche diodes may be arranged in a one-dimensional or two-dimensional array in a SPAD-based semiconductor device. The SPAD-based semiconductor device may also include a transparent cover glass that is formed over the array of SPADs. Each line of SPADs within the SPAD-based semiconductor device may be covered by a respective light spreading lens. The light spreading lens may be formed as a groove in an upper surface of the transparent cover glass. The light spreading lens may have a uniform cross-section along its length. The light spreading lens may be formed as a convex lens on an upper or lower surface of the transparent cover glass.

Abstract: A semiconductor package may include a line array of single-photon avalanche diodes (SPADs). The line array of single-photon avalanche diodes may be split between multiple silicon dice. Each silicon die may be overlapped by at least one lens to focus light away from gaps between the dice and towards the single-photon avalanche diodes. There may be one single-photon avalanche diode for each silicon die or multiple single-photon avalanche diodes for each silicon die. When there are multiple single-photon avalanche diodes for each silicon die, lenses may be formed over only the edge single-photon avalanche diodes.

Abstract: A semiconductor package may include a line array of single-photon avalanche diodes (SPADs). The line array of single-photon avalanche diodes may be split between multiple silicon dice. The silicon dice may have a staggered arrangement, with prisms on the package lid redirecting incident light to the silicon dice. The silicon dice may alternate between a first side of the package substrate and a second side of the package substrate. The prisms may alternate between a first structure that redirects incident light to the first side of the package substrate and a second structure that redirects incident light to the second side of the package substrate. The silicon dice may overlap to allow satisfactory alignment between the silicon dice and the prisms.

Abstract: A segmented optoelectronic semiconductor package may help to alleviate stresses resulting from bending that can cause a mechanical defect (e.g., crack) in a detector circuit. The bending can result from thermal growth/shrinkage of parts used in the optical electronic package and may be more pronounced for high aspect ratio detector circuits. The segmentation of the disclosed semiconductor package can create seams that allow the parts to flex without breaking. As a result, the disclosed semiconductor package may facilitate high aspect ratio optical detection over a wide temperature range.

Abstract: An imaging device may include single-photon avalanche diodes (SPADs). The single-photon avalanche diodes may be arranged in an array of microcells (such as a silicon photomultiplier). Each microcell may have an aspect ratio that is greater than 1. Each microcell may be covered by a microlens that also has an aspect ratio that is greater than 1. The microlens may have curvature in a first direction (parallel to the width of the microcell/microlens) and less curvature in a second direction that is orthogonal to the first direction (parallel to the length of the microcell/microlens). Forming non-square, rectangular microcells and microlenses in this fashion may allow for larger microcells that still have satisfactory microlens performance.

Abstract: A semiconductor device may include a plurality of single-photon avalanche diodes. The single-photon avalanche diodes may be arranged in microcells. Each microcell may be a split microcell with first and second independent microcell segments. Each microcell segment in the split microcell may have a respective single-photon avalanche diode that is coupled to an output line. The single-photon avalanche diode of each microcell segment may also be coupled to a respective resistor that is used to quench avalanches in the single-photon avalanche diode. Splitting the microcell may reduce the recovery time of each microcell. The segments of the split microcell may be positioned close together, even if susceptible to optical crosstalk. Intra-microcell isolation structures may be formed between the microcell segments. Inter-microcell isolation structures may be formed around a perimeter of the split microcell. The intra-microcell and inter-microcell isolation structures may be different.

Abstract: A semiconductor device may include a plurality of single-photon avalanche diodes. The single-photon avalanche diodes may be arranged in microcells. Each microcell may be a split microcell with first and second independent microcell segments. Each microcell segment in the split microcell may have a respective single-photon avalanche diode that is coupled to an output line. The single-photon avalanche diode of each microcell segment may also be coupled to a respective resistor that is used to quench avalanches in the single-photon avalanche diode. Splitting the microcell may reduce the recovery time of each microcell. The segments of the split microcell may be positioned close together, even if susceptible to optical crosstalk. Intra-microcell isolation structures may be formed between the microcell segments. Inter-microcell isolation structures may be formed around a perimeter of the split microcell. The intra-microcell and inter-microcell isolation structures may be different.

Abstract: A semiconductor package may include a line array of single-photon avalanche diodes (SPADs). The line array of single-photon avalanche diodes may be split between multiple silicon dice. The silicon dice may have a staggered arrangement, with prisms on the package lid redirecting incident light to the silicon dice. The silicon dice may alternate between a first side of the package substrate and a second side of the package substrate. The prisms may alternate between a first structure that redirects incident light to the first side of the package substrate and a second structure that redirects incident light to the second side of the package substrate. The silicon dice may overlap to allow satisfactory alignment between the silicon dice and the prisms.

Abstract: A semiconductor package may include a line array of single-photon avalanche diodes (SPADs). The line array of single-photon avalanche diodes may be split between multiple silicon dice. Each silicon die may be overlapped by at least one lens to focus light away from gaps between the dice and towards the single-photon avalanche diodes. There may be one single-photon avalanche diode for each silicon die or multiple single-photon avalanche diodes for each silicon die. When there are multiple single-photon avalanche diodes for each silicon die, lenses may be formed over only the edge single-photon avalanche diodes.

Abstract: An imaging device may include single-photon avalanche diodes (SPADs). Positioning SPADs close together in an imaging device (such as a silicon photomultiplier) may have benefits such as improved sensitivity. However, as the SPADs get closer together, the SPADS may become susceptible to crosstalk. Crosstalk is typically undesirable due to reduced dynamic range and reduced signal accuracy. To reduce crosstalk, a capacitor or other component may be coupled between adjacent SPADs. When an avalanche occurs on a given SPAD, the bias voltage may drop below the breakdown voltage. The capacitor may cause a corresponding voltage drop on a neighboring SPAD. The voltage drop on the neighboring SPAD reduces the over-bias of that SPAD, reducing the sensitivity of the SPAD and therefore mitigating the chance of crosstalk occurring.

Abstract: An imaging device may include single-photon avalanche diodes (SPADs). The single-photon avalanche diodes may be arranged in a one-dimensional or two-dimensional array in a SPAD-based semiconductor device. The SPAD-based semiconductor device may also include a transparent cover glass that is formed over the array of SPADs. Each line of SPADs within the SPAD-based semiconductor device may be covered by a respective light spreading lens. The light spreading lens may be formed as a groove in an upper surface of the transparent cover glass. The light spreading lens may have a uniform cross-section along its length. The light spreading lens may be formed as a convex lens on an upper or lower surface of the transparent cover glass.

Abstract: An imaging device may include single-photon avalanche diodes (SPADs). The single-photon avalanche diodes may be arranged in an array of microcells (such as a silicon photomultiplier). Each microcell may have an aspect ratio that is greater than 1. Each microcell may be covered by a microlens that also has an aspect ratio that is greater than 1. The microlens may have curvature in a first direction (parallel to the width of the microcell/microlens) and less curvature in a second direction that is orthogonal to the first direction (parallel to the length of the microcell/microlens). Forming non-square, rectangular microcells and microlenses in this fashion may allow for larger microcells that still have satisfactory microlens performance.

Abstract: A semiconductor device may include a plurality of single-photon avalanche diodes. The single-photon avalanche diodes may be arranged in microcells. Each microcell may be a split microcell with first and second independent microcell segments. Each microcell segment in the split microcell may have a respective single-photon avalanche diode that is coupled to an output line. The single-photon avalanche diode of each microcell segment may also be coupled to a respective resistor that is used to quench avalanches in the single-photon avalanche diode. Splitting the microcell may reduce the recovery time of each microcell. The segments of the split microcell may be positioned close together, even if susceptible to optical crosstalk. Intra-microcell isolation structures may be formed between the microcell segments. Inter-microcell isolation structures may be formed around a perimeter of the split microcell. The intra-microcell and inter-microcell isolation structures may be different.

Abstract: An imaging device may include single-photon avalanche diodes (SPADs). Positioning SPADs close together in an imaging device (such as a silicon photomultiplier) may have benefits such as improved sensitivity. However, as the SPADs get closer together, the SPADS may become susceptible to crosstalk. Crosstalk is typically undesirable due to reduced dynamic range and reduced signal accuracy. To reduce crosstalk, a capacitor or other component may be coupled between adjacent SPADs. When an avalanche occurs on a given SPAD, the bias voltage may drop below the breakdown voltage. The capacitor may cause a corresponding voltage drop on a neighboring SPAD. The voltage drop on the neighboring SPAD reduces the over-bias of that SPAD, reducing the sensitivity of the SPAD and therefore mitigating the chance of crosstalk occurring.

Abstract: An imaging device may include an active silicon photomultiplier and associated temperature and non-uniformity compensation circuitry configured to mitigate temperature and process variations on the device. The compensation circuitry may include a reference silicon photomultiplier, a constant current source that supplies a fixed current into the reference silicon photomultiplier, a voltage sensor for detecting a voltage output from the reference silicon photomultiplier, a data converter for converting the voltage output from the voltage sensor, and a voltage controller for generating an adjustable voltage for biasing the active silicon photomultiplier depending on the signal output from the data converter.