Solid-state imaging device
A solid-state imaging device with increased integration is provided. A pixel of the solid-state imaging device includes a photoelectric converter and a counter that counts a pulse signal output based on the amount of light incident on the photoelectric converter, wherein the counter may be divided into a lower bit group and an upper bit group, a first integrated circuit is provided between the lower bit group and the upper bit group, and the first integrated circuit may connect the lower bit group and the upper bit group of a plurality of pixels to each other.
1 . A solid-state imaging device comprising:
a plurality of pixels, each of the plurality of pixels comprising:
a photoelectric converter; and
a counter configured to count a pulse signal output based on an amount of light incident on the photoelectric converter, the counter comprising a first bit group counter among a plurality of first bit group counters and a second bit group counter among a plurality of second bit group counters; and
a first integrated circuit provided between the plurality of first bit group counters and the plurality of second bit group counters, and configured to connect each of the plurality of first bit group counters to a respective second bit group counter among the plurality of second bit group counters for each of the plurality of pixels in a time division manner.
2 . The solid-state imaging device of claim 1 , wherein the photoelectric converter comprises a single-photon avalanche diode (SPAD).
3 . The solid-state imaging device of claim 1 , further comprising:
a first layer and a second layer in a stacked structure,
wherein the plurality of first bit group counters are is provided in the first layer, and the plurality of second bit group counters provided in the second layer.
4 . The solid-state imaging device of claim 1 ,
wherein the counter of a first pixel among the plurality of pixels comprises a first first bit group counter and a first second bit group counter, and
wherein the first integrated circuit is further configured to:
perform a switching operation to connect the first first bit group counter and the first second bit group counter to each other in the time division manner, and
transmit a counter signal from the first first bit group counter to the first second bit group counter.
5 . The solid-state imaging device of claim 4 , further comprising:
a first layer and one or more second layers in a stacked structure; and
an interlayer connection electrode provided between the first layer and the one or more second layers,
wherein the first first bit group counter is formed in the first layer, and the first second bit group counter is formed in the one or more second layers different from the first layer, and
wherein the first first bit group counter is connected to the first second bit group counter through the first integrated circuit and the interlayer connection electrode.
6 . The solid-state imaging device of claim 5 , further comprising:
a pixel unit comprised of a plurality of pixels sharing the first integrated circuit,
wherein the plurality of second bit group counters corresponding to each of the plurality of pixels included in the pixel unit is formed in two or more different layers, and
wherein the interlayer connection electrode in a layer in which the plurality of first bit group counters are formed and the two or more different layers in which the plurality of second bit group counters are is formed is arranged spatially corresponding to each other.
7 . The solid-state imaging device of claim 6 , wherein two or more different layer structures in which the plurality of second bit group counters are arranged are formed to correspond to each other.
8 . The solid-state imaging device of claim 6 , further comprising:
a distribution circuit formed in each layer in which the plurality of second bit group counters are formed,
wherein the distribution circuit is configured to distribute the counter signal from the first first bit group counter through the interlayer connection electrode to the corresponding first second bit group counter.
9 . The solid-state imaging device of claim 8 ,
wherein the plurality of second bit group counters respectively corresponding to the plurality of pixels included in the pixel unit are formed in a first second layer, among the one or more second layers for each pixel, and the distribution circuit is provided in the first second layer, and
wherein the distribution circuit is configured to distribute the counter signal from the first first bit group counter sent from the first integrated circuit to the corresponding first second bit group counter.
10 . The solid-state imaging device of claim 1 , wherein, in each of the plurality of pixels, the photoelectric converter, the first bit group counter, and the second bit group counter are each formed in different layers, and an interlayer between a layer of the photoelectric converter and a layer of the first bit group counter and an interlayer between the layer of the first bit group counter and a layer of the second bit group counter are each connected to each other through interlayer connection electrodes.
11 . The solid-state imaging device of claim 5 , wherein an event signal related to a specific event occurring in the first second bit group counter is configured to be sent, through the interlayer connection electrode, from a layer in which the first second bit group counter is formed to a layer in which the first first bit group counter is formed.
12 . The solid-state imaging device of claim 1 ,
wherein the solid-state imaging device is configured to switch between a normal mode that outputs a counter signal for each pixel and a binning mode that outputs counter signals of the plurality of pixels by adding or averaging the counter signals of the plurality of pixels, and
in the binning mode, the first integrated circuit is configured to add or average counter signals of the plurality of first bit group counters of a plurality of pixels connected to the first integrated circuit, and transmit the added or averaged counter signal to at least one of the plurality of second bit group counters.
13 . The solid-state imaging device of claim 1 , further comprising a second integrated circuit configured to share and integrate an optical signal output of the photoelectric converter of the plurality of pixels.
14 . The solid-state imaging device of claim 13 ,
wherein the solid-state imaging device is configured to switch between a normal mode that outputs a counter signal for each pixel and a binning mode that outputs counter signals of the plurality of pixels by adding or averaging the counter signals of the plurality of pixels, and
in the binning mode, the second integrated circuit is configured to add or average optical signal outputs of the photoelectric converters of the plurality of pixels and send a counter signal based on the added or averaged optical signal outputs, to at least one of the plurality of first bit group counters.
15 . The solid-state imaging device of claim 1 , wherein the counter comprises a ripple counter.
16 . The solid-state imaging device of claim 1 , wherein at least one of the plurality of first bit group counters comprises a ripple counter, and at least one of the plurality of second bit group counters comprises at least one of a static random-access memory (SRAM), a dynamic random-access memory (DRAM), a latch, and a synchronous DRAM (SDRAM).
17 . A solid-state imaging device configured by stacking a plurality of layers, the solid-state imaging device comprising:
a plurality of pixels, each of the plurality of pixels comprising:
a photoelectric converter; and
a signal processing unit comprising:
a counter configured to count a pulse signal output based on an amount of light incident on the photoelectric converter, the counter comprising a first bit group counter and a second bit group counter formed in different layers among the plurality of layers.
18 . The solid-state imaging device of claim 17 ,
wherein the first bit group counter is formed in a first layer among the plurality of layers,
the second bit group counter is formed in a second layer among the plurality of layers, and
the second layer comprises one or more layers.
19 . The solid-state imaging device of claim 17 ,
wherein the first bit group counter and the second bit group counter are configured to be connected to each other through an interlayer connection portion,
wherein the interlayer connection portion comprises:
an integrated circuit formed on a same layer as the first bit group counter;
a distribution circuit formed on a same layer as the second bit group counter; and
a through electrode vertically connecting the integrated circuit to the distribution circuit.
20 . A solid-state imaging device including a pixel unit including a plurality of vertically and horizontally adjacent pixels, the solid-state imaging device comprising:
a counter configured to count pulse signals output based on an amount of light incident on each of the plurality of pixels, the counter comprising a first bit group counter and a second bit group counter,
wherein the second bit group counter corresponding to the plurality of pixels is arranged in at least two layers, and
wherein the first bit group counter corresponding to the plurality of pixels included in the pixel unit is arranged as one layer different from the at least two layers in which the second bit group counter is arranged.