Sumitomo Electric Industries, Limited

Sundararajan Balasekaran

Hiroshi Inada

Daisuke Kimura

Yasuhiro Iguchi

Kohei Miura

A light detection device includes a sensor array and a readout circuit. The sensor array includes a compound semiconductor substrate having a first main surface and a second main surface opposite to the first main surface, a plurality of photodetectors arranged two-dimensionally on the first main surface, and an insulating film disposed on the second main surface. The readout circuit includes a silicon substrate having a third main surface connected to the first main surface of the compound semiconductor substrate. The insulating film contains an insulating material having a lower thermal expansion coefficient than a compound semiconductor contained in the compound semiconductor substrate. The insulating film includes at least one first portion having a first thickness and a second portion having a second thickness larger than the first thickness.

Light detection device

A light receiving element is obtained by: forming a first mask having a first opening and a second opening; performing etching by using the first mask, to allow the etching to progress at a higher rate in the second opening than in the first opening; forming a second mask having a third opening and a fourth opening; performing etching by using the second mask, to form a mesa in a region interposed by the third opening, and an n-type contact region in the fourth opening; and forming a first electrode on the mesa and a second electrode on the n-type contact region, the first electrode being electrically connected to the third layer, the second electrode being electrically connected to the first layer, wherein a region covered with the first mask and exposed through the fourth opening of the second mask turns into the n-type contact region after the etching using the second mask.

Light receiving element and method of manufacturing the same

An infrared light receiving device includes: a structure having a supporting base and a laminate body, the laminate body including a first superlattice layer, a second superlattice layer and a semiconductor region, the first superlattice layer, the second superlattice layer and the semiconductor region being arranged sequentially on the supporting base, and the laminate body having an array of semiconductor mesas for photodiodes and a recess defining the array of semiconductor mesas; and a first electrode connected to the first superlattice layer. The first superlattice layer has an n-type conductivity. The semiconductor region has a p-type conductivity. The first superlattice layer has a type-II superlattice structure and forming a heterojunction with the supporting base. The recess has first and second recess portions. The second recess portion has a bottom in the first superlattice layer. The first recess portion has a depth larger than that of the second recess portion.

Infrared light receiving device, method for fabricating infrared light receiving device

An infrared detecting semiconductor device comprises: an optical absorbing layer of type-II disposed between first conductivity-type and second conductivity-type semiconductor layers; and an optical filtering film of n-type InGaAs having an n-type dopant concentration larger than 8&#xd7;10cm. The optical filtering film includes first to third semiconductor regions, which are sequentially arranged in a direction of a first axis on the optical filtering film. The first semiconductor region has an n-type dopant concentration of 2.0&#xd7;10cmor more. The third semiconductor region has a n-type concentration of 3.0&#xd7;10cmor less. The second semiconductor region has an n-type dopant profile monotonically changing from a first dopant concentration at a boundary between the first and second semiconductor regions to a second dopant concentration at a boundary between the second and third semiconductor regions. The first dopant concentration is greater than the second dopant concentration.

Infrared detecting semiconductor device

An infrared light-receiving device includes an optical absorption layer disposed on a principal surface of a substrate and an optical filter disposed on the optical absorption layer, the optical filter including first, second, and third semiconductor regions that are arranged in that order in a direction from the optical absorption layer to the optical filter, each of the first, second, and third semiconductor regions including an n-type InGaAs layer. The optical absorption layer includes a type-II superlattice structure. The first semiconductor region contains an n-type impurity with a concentration of 2.0&#xd7;10cmor more. The third semiconductor region contains an n-type impurity with a concentration of 3.0&#xd7;10cmor less and 8.0&#xd7;10cmor more. The second semiconductor region contains an n-type impurity with a concentration between the impurity concentration of the first semiconductor region and the impurity concentration of the third semiconductor region.

Infrared light-receiving device

A method includes: forming a first mask having a first opening and a second opening; performing etching by using the first mask, to allow the etching to progress at a higher rate in the second opening than in the first opening; forming a second mask having a third opening and a fourth opening; performing etching by using the second mask, to form a mesa in a region interposed by the third opening, and an n-type contact region in the fourth opening; and forming a first electrode on the mesa and a second electrode on the n-type contact region, the first electrode being electrically connected to the third layer, the second electrode being electrically connected to the first layer, wherein a region covered with the first mask and exposed through the fourth opening of the second mask turns into the n-type contact region after the etching using the second mask.

A light receiving device includes a substrate having a principal surface and a back surface including a light receiving surface; a metal wire disposed on the principal surface, the metal wire including a bonding portion having an opening; and photodiodes that is arranged in an array on the substrate, each of the photodiodes including an electrode connected to the bonding portion of the metal wire and a semiconductor mesa including a stacked semiconductor layer, the stacked semiconductor layer including a first semiconductor layer disposed on the substrate, an optical absorption layer including a type-II superlattice structure, and a second semiconductor layer. Each of the electrodes of the photodiodes is disposed on a side surface of the semiconductor mesa in contact with the first semiconductor layer. The first semiconductor layer faces to the light receiving surface through the opening of the bonding portion.

Light receiving device and method of producing light receiving device

An optical switching device includes: an optical absorbing layer having a first superlattice structure and responding to an incident light; an excitation layer having a second superlattice structure and producing an electron by thermal excitation; and a barrier layer having a third superlattice structure, the optical absorbing layer and the barrier layer enabling a first band offset and a second band offset to form a well in a conduction band of the second superlattice structure of the excitation layer with reference to a conduction band of the first superlattice structure of the optical absorbing layer and a conduction band of the third superlattice structure of the barrier layer, respectively.

Optical switching device, optical switching apparatus

An optical switch includes a first optical absorbing layer sensitive to a first light and having a first superlattice structure and a first bandgap; a second optical absorbing layer sensitive to a second light and having a second bandgap smaller than that of the first bandgap; and a barrier layer having a second superlattice structure. The first optical absorbing layer, the second optical absorbing layer, and the barrier layer are arranged in a direction of an axis to form an arrangement with a first band-offset in a conduction band of the first optical absorbing layer, a second band-offset in a conduction band of the barrier layer, and a well in a conduction band of the second optical absorbing layer.

Optical switch, optical switching apparatus

An infrared image sensor includes a bias circuit receiving a timing signal, the bias circuit generating a bias voltage having a first value and a second value in response to the timing signal; a semiconductor light-receiving device including a photodiode, the semiconductor light-receiving device receiving the bias voltage; a read-out circuit including a read-out electrode connected to the photodiode, the read-out electrode receiving an electrical signal from the photodiode; and a signal processing circuit processing a read-out signal from the read-out circuit synchronously with the timing signal. The photodiode includes an optical absorption layer made of a III-V group compound semiconductor. The optical absorption layer has a type II multi quantum well structure including first compound semiconductor layers containing antimony as a constituent element and second compound semiconductor layers that are stacked alternately.

Infrared image sensor

A light receiving device includes a substrate having a principal surface and a back surface, the substrate containing GaSb semiconductor co-doped with a p-type dopant and an n-type dopant; a stacked semiconductor layer disposed on the principal surface of the substrate, the stacked semiconductor layer including an optical absorption layer; and an incident surface provided on the back surface of the substrate that receives an incident light. The optical absorption layer includes a super-lattice structure including a first semiconductor layer and a second semiconductor layer that are alternately stacked. In addition, the first semiconductor layer contains gallium and antimony as constituent elements. The second semiconductor layer is composed of a material different from a material of the first semiconductor layer.

Light receiving device and image sensor

An active layer having a type 2 multi-quantum well structure includes a plurality of pair thickness groups having different thicknesses, including a first pair thickness group and a second pair thickness group. The first pair thickness group gincludes 10 to 100 pairs, each monolayer of the pairs having a thickness of 1.5 nm or more and less than 3.5 nm. The second pair thickness group gincludes 10 to 100 pairs, each monolayer of the pairs having a thickness of the minimum thickness (a second group minimum thickness) or more and 7 nm or less, the minimum thickness being larger than the maximum monolayer thickness 3.5 nm of the first pair thickness group.

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Yokohama, Japan

Sundararajan Balasekaran