CN106601763B

CN106601763B - Image sensor with solar cell function and electronic device thereof

Info

Publication number: CN106601763B
Application number: CN201610895572.XA
Authority: CN
Inventors: 金勋
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-10-14
Filing date: 2016-10-14
Publication date: 2020-01-31
Anticipated expiration: 2036-10-14
Also published as: CN106601763A; JP6308404B2; MY176378A; JP2017076798A

Abstract

A unit pixel element used as an image sensor or a solar cell according to the present invention includes a photodetector that drives a photocurrent induced by incident light on a gate electrode to flow along a channel between a source electrode and a drain electrode, an th switch th switch that is wire-connected between a source terminal of the photodetector and a th solar cell bus line and is turned on or off, and a second switch that is wire-connected between a gate terminal of the photodetector and a second solar cell bus line and is turned on or off, and is characterized by functions of light energy collection and high-efficiency photoelectric conversion that generate and supply effective electric power.

Description

Image sensor with solar cell function and electronic device thereof

Technical Field

The present invention relates to kinds of image sensors that can be used as solar cells and electronic devices using the image sensors having a solar cell function, and more particularly to kinds of technologies that operate as solar cells in a normal case, but by shifting to a specific mode when necessary.

Background

Light energy collection is a technology that establishes inevitable requirements for the internet of things (IoT), the Ubiquitous Sensor Network (USN), the Wireless Sensor Network (WSN), and the like, and provides semi-permanent power supply for various electronic devices related to these fields.

have attempted to achieve the goal of integrating optical energy conversion devices onto other circuits by using P-N junction photodiode technology from CMOS processes to fabricate optical energy conversion devices similar to Integrated Solar Cells (ISCs), but such photodiodes exhibit low photoelectric conversion efficiency, are not sufficient to provide sufficient electrical power to the circuits on the chip, and th paragraphs are a long way to fully integrate solar cell processes with standard CMOS processes.

The present invention relates to related methods and technical ideas, which are improved on the basis of a registered patent "pixel unit of image sensor and photodetector thereof" (us8,569,806b2, us8,610,234b2 and US8,669,599B2) to provide pixelized chip-integrated solar cell System (SOC) tothis end, the structures and operations of the photodetector and the pixelized solar cell manufactured by a standard CMOS process are described, and methods of thus manufacturing a solar cell pixel sharing single cells with the image sensor pixel, thereby selecting each function as needed are proposed.

Disclosure of Invention

Technical problem

Therefore, in order to solve the above problems, the present invention provides methods to make the solar cell pixels configured with high efficiency photodetectors share single cells with the image sensor pixels, and select any of the two functions as needed, i.e., as image sensors or as solar cells to generate and store driving energy.

Technical scheme

array elements which can be either an image sensor or a solar cell according to embodiments of the present invention include sub-elements each of which arranges two or more unit pixel elements in the th direction, and sub-element switches which are turned on or off between the sub-elements to arrange two or more sub-elements in the second direction, wherein the sub-elements include photodetectors which drive a photocurrent induced by incident light incident on a gate to flow along a channel between a source and a drain, and the unit pixel elements include th and second switches which connect terminals of the photodetectors to th and second solar cell buses.

According to another embodiments of the invention, array elements that can be an image sensor or a solar cell include sub-elements that arrange two or more unit pixel elements in the th direction, and element switches that are turned on or off between the sub-elements to arrange two or more sub-elements in the second direction, wherein the sub-elements include photodetectors that drive photocurrent induced by incident light incident on a gate electrode to flow along a channel between a source and a drain, and

electronic devices having technologies that can be used as image sensors or solar cells according to embodiments of the present invention include an image sensor section including two or more unit pixels capable of functioning as solar cells according to control signals, and a processor generating and transmitting the control signals to the image sensor section, wherein each unit pixel includes a photodetector that drives a photocurrent induced by incident light incident on a gate electrode to flow along a channel between a source electrode and a drain electrode.

Advantageous effects

According to embodiments of the present invention, techniques are provided, which can be used as an image sensor having a light energy collecting function and can efficiently generate and supply energy.

Furthermore, the technologies of the preferred embodiments according to the invention can be fabricated to be easily fully integrated onto adjacent circuits including the image sensor, all of which are also fabricated by CMOS processes.

Drawings

FIG. 1 is a cross-sectional view of a photodetector showing high efficiency photoelectric conversion according to the present invention;

FIG. 2 is a cross-sectional view for describing a high-efficiency photoelectric conversion mechanism of a photodetector according to the present invention;

FIG. 3 is a cross-sectional view of a photodetector for a solar cell in accordance with the present invention;

FIG. 4 is a cross-sectional view for describing a power generation mechanism of a photodetector according to the present invention;

FIG. 5 is a cross-sectional view of the Voc acquisition mechanism of a photodetector according to an embodiment of the present invention;

FIG. 6 is a cross-sectional view of the Voc acquisition mechanism of a photodetector according to a second embodiment of the present invention;

FIG. 7 illustrates a configuration of a solar cell unit pixel according to the present invention;

FIG. 8 illustrates a Voc acquisition mechanism in a pixel array according to an th embodiment of the invention;

FIG. 9 illustrates a Voc acquisition mechanism in a pixel array according to a second embodiment of the present invention;

fig. 10 is a schematic structural view of a unit pixel of an image sensor according to an embodiment of the present invention;

fig. 11 is a schematic structural view of a unit pixel of a solar cell according to an embodiment of the present invention;

fig. 12 is a schematic structural view of a second unit pixel of an image sensor according to a second embodiment of the present invention;

fig. 13 is a schematic structural view of a second unit pixel of a solar cell according to a second embodiment of the present invention;

FIG. 14 is an image sensor array according to the present invention;

FIG. 15 is an array element for use as an image sensor or solar cell according to the present invention;

fig. 16 is a block diagram of an electronic device used as an image sensor or a solar cell according to the present invention.

Detailed Description

While the invention is susceptible to various modifications and embodiments, reference will now be made in detail to specific embodiments illustrated in the accompanying drawings and description, however, the structural and functional descriptions used in the embodiments are merely illustrative of the embodiments and should not be construed as limiting the invention to the specific modes of carrying out the invention but should be construed as encompassing all modifications, equivalents, and alternatives within the spirit and scope of the invention.

Those numbers referred to in this specification are simply for the purpose of distinguishing an element from an element identifier, e.g., , second, etc.

elements of the invention are described as being "connected," "linked," etc. to other elements, it should be understood that the elements may be explicitly connected, linked, etc. to the other elements, or it should be understood that the elements may be connected, linked, etc. to the other elements unless stated to the contrary.

Preferred embodiments of the present invention will now be described in more detail with reference to the accompanying drawings.

Fig. 1 is a cross-sectional view of a photodetector showing high-efficiency photoelectric conversion according to the present invention.

As shown in fig. 1, a light receiving device of a unit pixel, which corresponds to a photodetector, is established by a tunnel junction device, not by an existing photodiode, a tunnel junction device in which a thin insulating layer is sandwiched between two conductors or two semiconductors is defined as an electronic element that operates by using a tunneling effect generated in the insulating layer, for information purposes, the tunneling effect is a phenomenon in which particles move as quantum mechanical-based terms, a driving force having a potential that is greater than a kinetic energy that the particles have exerts acts, passing through regions.

The embodiments of the invention provide methods to produce light receiving devices and solar cells for use as unit pixels with photodetectors where the term "photodetector" as used in the specification and claims refers to light receiving devices and solar cells implemented with tunnel junction devices.

As shown in fig. 1, the photodetector 100 has a PMOS structure the photodetector 100 is disposed on a P-type substrate 110 as designated in fig. 1, the P-type substrate 110 including P + diffusion layers 120 and another P + diffusion layers 130 corresponding to the source and drain of a common NMOS, respectively, according to the present invention, every P +

diffusion layers

120, 130 are referred to as the "source" and "drain" of the photodetector, respectively.

An active electrode 121 and a drain electrode 131 wired to an external node are respectively disposed on top of the source 120 and top of the drain 130.

The N-well 115 is disposed on N-type impurities doped into the P-type substrate 110 for the photodetector 110. The N well thus provided is constructed on the source 120 and the drain doped with P-type impurities. In addition, a thin oxide layer 140 is disposed between the source and

drain electrodes

120 and 130, and a polysilicon region doped with N-type impurities corresponding to a gate of a general MOSFET is disposed on the top of the oxide layer 140. The polysilicon 150 region serves as a light receiving element in the photodetector, and thus the polysilicon 150 is hereinafter referred to as a "light receiving portion".

The light receiving portion 150 on the oxide layer 140 is distant from the source 120 and the drain 130. Tunneling is formed on the way from the light receiving part 150 to the source electrode 120 or the drain electrode 130, and it is preferable that the thickness of the oxide layer 140 is 10 nm or less than 10 nm to promote the tunneling effect.

In the photodetector 100, a metal, light shielding layer may cover an area other than the top of the light receiving section 150, which is not the case of a normal MOSFET. In contrast, the photodetector 100 limits incident light only on the light receiving portion using the light shielding layer, thereby maximizing photoelectric conversion efficiency.

The photodetector 100 may be fabricated by the same standard CMOS process as used to fabricate the other circuits, and the photodetector 100 may be used as the portion of the integrated system responsible for seamless integration and various applications.

Fig. 2 is a cross-sectional view for describing a high-efficiency photoelectric conversion mechanism of the photodetector 100 according to the present invention, the photodetector 100 allows light to pass through the top of a light-receiving portion, and then the light generates electron-hole pairs (EHPs) to generate -determined electric field between the light-receiving portion 150 and the source 120 or the drain 130. the voltage between the source electrode 120 and the drain electrode 131 should reach a certain -determined value, charges excited by light tunneling from the light-receiving portion pass through the oxide layer 140 into the source 120 or the drain 130. holes are depleted by charge tunneling, and electrons flow into the light-receiving portion 150 such that the charge amount of electrons exceeds the charge amount of holes.

According to the present invention, incident light reaches only the top of the light receiving part 150 of the photodetector 100, the light receiving part is opened to the outside to allow light of different wavelengths to enter, and in turn, depending on the wavelength of the light, the light is absorbed by the light receiving part 150 or passes through the light receiving part 150 to reach the lower side of the N well 115 or the lower side of the substrate 110. For example, the light receiving part 150 may have a thickness of 150 nm or more than 150 nm, and blue light or short wave light cannot reach the substrate 100 but is mostly absorbed by the light receiving part 150. The present invention provides a photodetector 100 which is different from the conventional photodetector in that even if any short-wave light is absorbed by the light receiving portion 150 and cannot reach the lower surface of the substrate, the change in the amount of charge in the light receiving portion 150 caused by the energy absorbed by the light receiving portion 150 drives a current along the channel, which is advantageous for the detection of the short-wave light, and when all the remaining light of other wavelengths is transmitted through the light receiving portion 150, a similar phenomenon occurs in the light receiving portion 150 and the threshold voltage of the current channel is changed.

Meanwhile, light of a relatively long wavelength sufficient to transmit the light receiving part 150 also generates electron-hole pairs (EHPs) in the N-well 115, thereby accumulating electrons, and as shown in FIG. 2, a channel has an influence on a change in threshold voltage under the N-well 115. the photodetector 100 manufactured according to such a method exhibits not only very high sensitivity but also a performance of driving a very large current by a minute amount of light even though photons are detected.A photodetector 100 of the present invention may also be used as an image sensor and a solar cell.

On the basis of such a photodetector in which a solar cell function is newly added, a solar sensor chip serving as a System On Chip (SOC) will be proposed below. While PMOS type configurations are described in fig. 1 and 2, NMOS type configurations and other similar configurations may also be established, all of which must be construed to be included in the claims of the present invention.

Fig. 3 is a sectional view of a photodetector for a solar cell according to the present invention, and fig. 4 is a sectional view for describing a power generation mechanism of the photodetector 300. When operating as a solar cell, photodetector 300 includes a photocurrent generated according to absorption of light, and photodetector 300 also generates a photovoltaic electromotive force (Photo voltage).

As shown in fig. 3, in the photodetector 300, electrons tunnel from a channel between the source 120 and the drain 130 to the light receiving portion 350 through the oxide layer 140 by virtue of the light being absorbed by the light receiving portion 350, which changes the entire charge amount of the light receiving portion 350. By measuring the voltage applied between the light receiving part 350 and the drain 130, the change in the amount of current caused by light can be estimated. Also, the charge accumulated in the N-well 115 can be estimated by measuring the voltage between the drain 130 and the

electrode

131, 361 of the W-RST 360.

As shown in fig. 4, in the photodetector 300, if the optical energy is greater than the threshold voltage of the transistor determined in the manufacturing process, the photocurrent flows along the channel.

More specifically, the silicon interface is originally designed to have threshold voltages, which are just below the subthreshold voltage, between the source 120 and the drain 130 where the channel 160 is established, wherein no photocurrent flows along the channel 160 without incident light being irradiated onto the light receiving part 350.

When the light energy is greater than the energy of combining charges with impurities doped in the light-receiving portion 350, a large number of electrons and holes in the light-receiving portion freely move on any side of the oxide layer 140, the oxide layer 140 acts as a barrier preventing each type of charge from crossing to the opposite side in an equilibrium state, before recombination between electrons and holes, essentially each resulting electron-hole pair (EHP) exists as an electron and a hole for a fixed period of and migrates to a region where an electric field is concentrated.

Since the potential of the silicon interface is just below the subthreshold between the source and drain 130, electrons or holes tunnel from the light-receiving portion 350 to the source 120 or drain 130, and this lowers the threshold voltage of the channel 160 due to an increase in the amount of charge and an electric field that becomes dense driven by incident light irradiated onto the light-receiving portion 350, and in turn, the flow of photocurrent is proportional to the amount of light of the channel 160.

The voltage driving the photocurrent may be detected by the light receiving part 350 or the N-well 115. The voltage values thus measured may range from a few nanoamperes to a few microamperes depending on the amount of light measured through the N-well 115, such that the voltage difference ranges from 0.1 to 1V. The measured values do not include any influence of dark current, and such outputs are obtained from pixels of 3 μm or less than 3 μm. Therefore, by constituting and controlling a pixel array by connecting a plurality of pixels in series or in parallel, a considerable output can be obtained.

Fig. 5 is a cross-sectional view of the Voc acquisition mechanism of a photodetector 300 according to an embodiment of the present invention.

As shown in fig. 5, a voltage of magnitude should be applied between the source 120 and the drain 130 to drive a photocurrent to flow, and incident light irradiated onto the light receiving part 350 changes a threshold voltage longer wavelength light transmits through the light receiving part 350 and is then absorbed by the N-well 115 and generates magnitude of charge in the N-well 115, which in turn accumulates around the interface of the channel, which causes generation of charge in the light receiving part 150 according to the same principle.

The photocurrent flowing along the channel is driven by a voltage generated by the amount of charge generated in the light receiving part 350 and the N-well 115. More specifically, the photocurrent thus driven generates V_Drain-GateOr a voltage between the drain 130 and the light receiving part 350, and V_Drain-WrstOr a voltage between the light receiving part 350 and the N-well 115. Therefore, by measuring V applied between the terminal 131 wired to the drain 130 and the terminal 351 wired to the light receiving part 350_Drain-GateValue, and V applied between a terminal 131 wired to the drain 350 and a terminal 361 wired to the N-well 115_Drain-WrstTo obtain Voc, from any values.

Fig. 6 is a cross-sectional view of the Voc acquisition mechanism of a photodetector 300 according to a second embodiment of the present invention.

Not only a large amount of photocurrent from the photodetector 300 but also a large amount of Voc is required to obtain a larger output. In this regard, as shown in FIG. 6, if the light receiving part is to be summedTerminal 351 connected to line 350 is connected to terminal 361 connected to N + diffusion layer 360 to raise the threshold of the channel, and the voltage V is larger_{Drain-(gate-wrst)}May be applied between a terminal for connecting the light receiving part 350 and the N well 115 and a terminal 351 wired to the drain 130, since the amount of charge is greatly increased when electrons under the N well 115 move to the N + diffusion layer 360.

Fig. 7 shows a configuration of a solar cell unit pixel, in which a solar cell including a unit pixel 700 is used as a pixelated solar cell, according to the present invention.

The unit pixel 700 includes a photo detector 300, a th switch Ms, a second switch Mg, a third opening light Mwr, a fourth switch Mv, a th solar cell bus SCB 1 and a second solar cell bus SCB 2. the photo detector 300 generates a photo current along a channel between a source and a drain, the photo current being driven by light hv incident on a light receiving portion or a gate, the second switch Mg, wired between a source terminal of the photo detector 300 and the th solar cell bus SCB 1, is used in an ON or OFF state, the second switch Mg, wired between a light receiving portion or a gate (a terminal of the photo detector 300) and the second solar cell bus SCB2, is used in an ON or OFF state, the third opening light Mwr, wired between a reset terminal connected to an N well or a substrate of the photo detector 300 and the second solar cell bus SCB2, is used in an ON or OFF state, impurities doped in the reset terminal are different from impurities doped in the source and drain, referring to FIGS. 3 to 6, different from those injected into the source and drain, the impurities are injected into the source and the drain, the drain is added to the drain, the impurities, when the drain is added to the drain, the impurity doped impurities, the drain is added to the drain, the drain is added to the drain, the drain is added to the drain is added to.

Meanwhile, the photodetector 300 may use the same power source as that used by the adjacent circuit because the photodetector 300 is manufactured in the same process as that of the adjacent circuit. In this case, unlike the existing photodetector, the photodetector 300 according to the present invention can be configured to use the power source used by the adjacent circuit itself without using any additional external power source.

As incident light is irradiated on the photodetector 300, a photocurrent flows on the way from the th solar cell bus SCB 1 to the second solar cell bus SCB2, while Voc is obtained between the th solar cell bus SCB 1 and the second solar cell bus SCB2 by controlling the second switch Mg and the third switch Mwr.

Alternatively, the second switch Mg and the third switch Mwr may be on/off actively connected to an external matrix, such as a row decoder, and the second switch Mg and the third switch Mwr may be turned on to the second solar bus SCB2, whether in an alternating pattern or in synchronization. The second switch Mg and the third switch Mwr are made to be connected to the external matrix at the same time, which can obtain a larger value of Voc than the light receiving portion and the N-well of the photodetector 300 are connected to the second solar bus SCB2, respectively, as shown in fig. 6,

FIG. 8 shows a Voc acquisition mechanism in a pixel array according to an embodiment of the invention, a pixel array 800 includes subelements 810, each subelement 810 having or more unit pixel elements 700 arrayed in a direction, and subelement switches 820 being turned on or off between the subelements 810 to array two or more subelements 810 in a second direction, as shown in FIG. 7, wherein the subelements 810 include photodetectors 300, the photodetectors 300 causing photocurrent to flow between source and drain under the influence of incident light impinging on the gate, and unit pixel elements 700, the unit pixel elements 700 including a switch Ms and a second switch Mg, the unit pixel elements 700 connecting terminals of the photodetectors 300 to a th solar cell bus SCB 1 and a second solar cell bus SCB 2. furthermore, the unit pixel elements 700 may include a third switch Mwr connecting the photodetectors 300 to the second solar cell bus SCB 2.

The sub-element switch 820 is used to switch on or off the second solar cell bus SCB2 of the th sub-switch 810 and the th solar cell bus SCB 1 of the second sub-switch 830.

Voc acquired in the unit pixel 700 of the pixel array 800 is defined as an open voltage acquired between a drain and a gate or between a drain and an N-well, and if the pixels are arranged in such an array by adjusting the connection between the pixels, a large value of Voc can be acquired. The same value of V1 as Voc is applied between every two adjacent columns, for which the series connection of n columns makes the overall output Voc nV1 of very important value. As shown in fig. 8, SCB lines may be connected in series, with each SCB line being routed between every two columns, by controlling the subelement switches 820 to output the sum of the voltages for each column. Thus, the output may be adjusted, taking into account that the appropriate Voc value is determined by controlling the sub-element switch 820.

FIG. 9 shows a Voc acquisition mechanism in a pixel array according to a second embodiment of the present invention, as shown in FIG. 8, a pixel array 900 includes -th control section 910 in addition to the sub-element 810 and the sub-element switch 820. the -th control section 910 issues independent control signals to the -th switch and the second switch of the plurality of unit pixel elements and then transfers the independent control signals to each unit pixel in the pixel array 900. the -th control section 910 may be expressed as a decoder and a matrix controller, and then the -th control section 910 decodes the control signals transferred from the processor and then transfers the decoded control signals to each unit pixel.

In the case of adding the third subelement 940 and the fourth subelement 950 to the existing th subelement 810 and the second subelement 830, by turning on the th subelement 810 and the second subelement 830 to the th subarray switch 820 and the internal bus SCB, while by turning on the third subelement 940 and the fourth subelement 950 to the second subarray switch 960 and the internal bus SCB, the second control section 920 generates and transmits a control signal to each subelement so that the th subelement 810 and the third subelement 940 share the th solar cell bus SCB 1 and the second solar cell bus SCB2 with the second subelement 830 and the fourth subelement 950, therefore, by connecting the th subelements 810 and the second subelement 830 corresponding to two longitudinal columns to the internal bus SCB, it is possible to obtain a double Voc, and detect the photocurrent induced by the photo-cell bus by the th solar cell bus 1 and the second solar cell bus SCB 2.

In the same manner, by connecting the third sub-element 940 and the fourth sub-element 950 corresponding to two columns to the internal bus SCBs, a double amount of Voc can be obtained, and photo-induced photo-current and Voc, which can be stored in the capacitance of the chip constituting the unit pixel element 700 or the external battery, are detected through the -th solar cell bus SCB 1 and the second solar cell bus SCB 2.

Also, the th control 910 can selectively designate pixel elements that facilitate photoelectric conversion and automatic interrupt voltage generation when the capacitor or battery is charged with a sufficient amount of power it is clear that the th and

second controls

910, 920 can be established by the physical controls of the single and the processor in the electronic device.

FIG. 10 is a schematic view showing a structure of a unit pixel of an image sensor according to an embodiment of the present invention, the unit pixel 1000 is provided with a selection device SEL connected to a photodetector 300, and the unit pixel 1000 can be connected to the image sensor via a column bus CB, which includes an IVC circuit 1010 as a DC voltage converting circuit, wherein the SEL can be constructed in the form of, for example, a MOSFET structure, and other various devices.

When SEL is turned on, a photo-current of photoelectric conversion in the photodetector 300 of the unit pixel 1000 starts to be accumulated in the capacitor 1015 of the IVC circuit 1010, the photo-current stored in the capacitor 1015 will be output as a voltage by the amount IVC _ OUT and a signal thereof is transmitted to a circuit including CDS (common double sampling). When the selection device SEL is turned on, if BUS _ RST is turned on, the column BUS CB and the photodetector 300 and the capacitor 1015 in the IVC circuit 1010 are directly connected to the ground GND, discharging the accumulated charges and resetting the signal. The integration time required for the image sensor can be defined by these aforementioned activities.

Fig. 11 is a schematic view of a structure of a unit pixel of a solar cell according to an th embodiment of the present invention the unit pixel 1100 is a solar cell in which the unit pixel 1000 of the 1T type image sensor shown in fig. 10 has been implemented, for this purpose, the unit pixel 1100 as a solar cell may be established using the image sensor shown in fig. 10 by adding th and second solar cell buses SCB 1 and 2SCB 2 and switches S1 and S2.

More specifically, the unit pixel 1100 includes a photodetector 300 generating a photo current driven to move along a channel between a source and a drain by incident light of a gate, a th switch S1 connecting a gate terminal of the photodetector 300 and a th solar cell bus SCB 1 to be connected or disconnected, and a selection device SEL connecting a source terminal of the photodetector 300 and a second solar cell bus SCB2 to output the photo current to the pixel output terminal 1010, wherein the pixel output terminal 1010 corresponds to the IVC circuit 1010 shown in fig. 10 and 11, while the unit pixel 1100 may additionally include a second switch S2 connecting the selection device and the pixel output terminal 1010 to be connected or disconnected, electric power is generated by the photo current and Voc, which is between the th solar cell bus SCB 1 and the second solar cell bus SCB2 by connecting the th solar cell bus SCB 1 and the gate of the photodetector 300 via the switch S1, and the second switch SCB2 is connected as the second solar cell bus SCB2 via the , and the second switch S2 is connected to obtain an image when the second solar cell bus is connected as the aforementioned second solar cell switch S9626, in other words, the unit pixel is connected as the solar cell switch S , the same time when the second solar cell bus is connected or disconnected, the second solar cell bus is connected as the aforementioned solar cell switch S , the solar cell bus is connected as the solar cell switch 2, in other words, the same operation as the solar cell switch S3628, the solar cell bus 3628, wherein the solar cell bus , the solar cell bus is connected as the solar cell.

Further, the pixel output terminal 1010 includes a capacitor 1015 that connects the second solar cell BUS SCB2 and the ground GND and stores the photocurrent, and a reset device BUS _ RST that is wired in parallel to the capacitor 1015 and connects the second solar cell BUS SCB2 and the ground GND.

Fig. 12 is a schematic structural view of a second unit pixel of an image sensor according to a second embodiment of the present invention. The second unit pixel 1200 further includes a reset device RST which is wired to the well of the photodetector 300, as shown in fig. 10, in addition to the existing photodetector 300 and the selection device SEL. The unit pixels 1200 can operate as an image sensor by connecting each column of unit pixels to the IVC circuit 1010. When the selection device is turned on, the photo-current of the photo-electric conversion in the photodetector 300 is stored in the capacitor 1015 of the IVC circuit 1010. Whereby the photo-charges stored in the capacitor 1015 will be output as a voltage, the output being IVC-OUT, and its signal is transmitted to a circuit including CDS.

When the selection device SEL is turned on, if _ RST is turned on, the column bus SC and the photodetector 300 and the capacitor 1015 in the IVC circuit 1010 are directly connected to the ground GND, discharging the accumulated charges and resetting the signal.

The reset device RST may be used when the signal is not reset seamlessly via the photodetector 300 or to manually adjust the threshold voltage of the current channel-the reset device RST may also be used to acquire images exclusively at high frame rates without delay, etc.

Fig. 13 is a schematic structural view of a second unit pixel of a solar cell according to a second embodiment of the present invention, the second unit pixel 1300 is a solar cell in which the unit pixel 1200 of the 2T type image sensor shown in fig. 12 has been implemented, the second unit pixel 1300 includes a photo detector 300 driving a photo current caused by incident light of a gate to flow in a channel between a source and a drain, an th switch S1 connecting a gate terminal of the photo detector 300 and a th solar cell bus SCB 1, on or off, a second switch S2 connecting a reset terminal of the photo detector 300 and a th solar cell bus SCB 1, on or off, a selection device SEL connecting a source terminal of the photo detector 300 and the second solar cell bus SCB2 to output the photo current to a pixel output terminal 1010, and another reset device RST wired to a well of the photo detector 300, wherein the reset terminal RST is doped with a different impurity from that in the source and drain.

The second unit pixel 1300 may further include a third switch S3 connecting the selection device SEL and the pixel output terminal 1010, on or off, when the th switch S1 or the second switch S2 is turned on and the third switch is turned off, the unit pixel operates as a solar cell, when the th switch S1 and the second switch S2 are turned off and the third switch S3 is turned on, the unit pixel operates as an image sensor, and the th switch S1 and the second switch S2 may be simultaneously turned on to obtain a greater Voc amount.

The pixel output terminal 1010 includes a capacitor 1015 which wires the second solar cell BUS SCB2 and the ground GND storing the photocurrent, and a reset device BUS _ RST which wires the second solar cell BUS SCB2 and the ground GND and wires are connected in parallel to the capacitor 1015, according to the configuration thereof, electric power is generated by the photocurrent and Voc, Voc being obtained between the th solar cell BUS SCB 1 and the second solar cell BUS SCB 2.

Fig. 14 is an image sensor array according to the present invention the image sensor array 1400 is used as a high-sensitivity image sensor when a row decoder and matrix controller 1410 and a column decoder and matrix controller 1420 transmit a photo-electrically converted photo-current in each columns of unit pixels 1000, 1200 to an IVC circuit array 1300 in which columns of IVC circuits are arranged in a direction parallel to the columns, and an IVC circuit array 1430 converts the photo-current into a voltage signal and transmits the voltage signal to a CDS, etc., according to the configuration, it is possible to build a high-sensitivity, high-rate image sensor.

Since the unit pixels are very simple and small in structure and size, respectively, it is possible to acquire an image in a frame rate range of 500 to 10000fps, as with the commonly used global block , by providing capacitors in the unit pixels, thereby simultaneously storing data and reading data at high speed in the analog memory.

The unit pixels according to embodiments of the present invention are two-dimensionally arranged, and the unit pixels may be arranged in an array to constitute frames, including 640 × 480, 1280 × 720, 1920 × 1080, etc., in existing VGA, HD, or full HD formats, or 4K UHD including 3840 × 2160, 4096 × 2160, etc., or 8K UHD including 7680 × 4320.

The present invention provides a unit pixel in which a photocurrent is greater than that of a conventional photodiode, which is caused based on the aforementioned structure, because the difference from the conventional photodiode technology is that brightness and darkness are distinguished only by the amount of charge stored in an electrostatic capacitor, the unit pixel controls a current to flow along a source-drain channel due to a change in the amount of charge due to a field effect caused by incident light of a light receiving region and simultaneously receives charge via a drain, which itself amplifies a signal.

Fig. 15 is an array element used as an image sensor or a solar cell according to the present invention, the array element 1500 includes a sub-element 1501 in which two or more unit pixel elements are arranged in the th direction, and a sub-element switch 1502 which connects and turns on or off the sub-element to arrange the sub-element in the second direction, wherein the sub-element 1501 includes, as shown in fig. 11 and 13, a photodetector 300 which generates a photocurrent flowing along a channel between a source and a drain, a plurality of switches S1-S3 and SEL which connect terminals of the photodetector with the th solar cell bus line and the second solar cell bus line, and a unit pixel element 1100, 1300 which includes a pixel output terminal 1010 which is connected to the second solar cell bus line and stores the photocurrent by voltage.

The sub-element switch 1502 may be wired and turned on or off between the second solar cell bus SCB2 of the th sub-element 1501 and the second solar cell bus SCB2 of the second sub-element 1503, or, as shown in fig. 8 and 9, wired and turned on or off between the second solar cell bus SCB2 of the th sub-element 1501 and the second solar cell bus SCB2 of the second sub-element 1503.

The array element 1500 may further include an control section 1510 generating respective signals to a plurality of switches S1-S3 and SEL in two or more unit pixel elements, wherein as shown in FIG. 13, a third switch S1 is wired between the gate terminal of the photodetector 300 and a th solar cell bus SCB 1 and is turned on or off, and a selection device SEL is wired between the source terminal of the photodetector 300 and a second solar cell bus SBC 2 to output a photocurrent so as to be induced to a pixel output terminal 1530 at the same time, the photodetector 300 may further include a second switch S2 wired between the reset terminal of the photodetector 300 and a th solar cell bus SCB 1 and is turned on or off, and/or a third switch S3 wired between the selection device SEL and a pixel output terminal 1010 and is turned on or off, wherein the reset terminal is doped with impurities different from those doped in the source and drain.

In addition, the th sub-cell 1501 and the second sub-cell 1502 can share the th and second solar cell buses SCB 1 and SCB2 to generate photovoltaic electromotive force as needed, therefore, as shown in FIG. 11 or FIG. 13, the th solar cell bus SCB 1, the second solar cell bus SCB2, and a plurality of switches can be embedded in the array element 1500 to convert the image sensor of the image sensor array into a solar cell.

Fig. 16 is a block diagram of an electronic device serving as an image sensor or a solar cell according to the present invention. The electronic device 1600 is an image capturing device, including a digital camera, a closed circuit television, and other devices of different types, such as a smart phone, a tablet computer, and a television, and is characterized by an image capturing function. The electronic device 1600 includes an image sensor portion 1610 including a plurality of unit pixels that can function as a solar cell according to a control signal; a processor 1620 which generates a control signal and transmits the control signal to the image sensor portion 1610; a battery 1630 that obtains electric power from the charged image sensor section 1610; and an electric power IC1640 that obtains electric power from the charged image sensor section 1610 or the battery 1630, wherein each unit pixel includes a photodetector that generates a photocurrent, which is induced by gate incident light, flowing along a channel between the source and the drain.

Meanwhile, if there is no case where the image sensor part 1610 functions as an image sensor, the processor 1620 transmits a control signal to the image sensor part 1610 so that the image sensor part 1610 can function as a solar cell.

In addition, the electronic device 1600 may further include an ambient light sensor 1650 for collecting ambient light and providing ambient light information to the processor 1620 if the intensity of the light exceeds a certain value, such that the processor 1620 generates the control signal.

Further, as shown in FIG. 7, each unit pixel may further include an th switch S1 that is wired and turned on or off between the source terminal of the photodetector 300 and the th solar cell bus SCB 1, and a second switch S2 that is wired and turned on or off between the gate terminal of the photodetector 300 and the second solar cell bus SCB 2.

Still further, referring to FIG. 11, each unit pixel may further include an th switch S1 that is wired and turned on or off between the gate terminal of the photodetector 300 and the th solar cell bus SCB 1, and a selection device SEL that is wired and turned on or off between the source terminal of the photodetector 300 and the second solar cell bus SCB2 and outputs a photocurrent to the pixel output terminal 1010.

For this purpose, the image sensor portion 1610 may serve as a Pixelated CMOS Solar Cell (PCSC) and be fabricated in a single chip by a standard CMOS process, in which an image sensor is also embedded, while achieving miniaturization and low power consumption. Also, the electric power generated by the image sensor section 1610 may be stored in a battery 1630, such as a secondary battery, so that the electric power IC1640 can obtain electric power supply as needed without a separate external power supply.

The above description is merely an example of the present invention, and those skilled in the art to which the present invention pertains can make modifications and improvements without departing from the technical idea or essential characteristics of the present invention.

In this connection, the embodiments given in the present description must be interpreted as illustrative and not limiting the technical idea of the invention each element of the integrated assembly as a single according to the embodiments of the invention may for example be divided into a plurality of elements to be implemented, whereas the elements as a plurality of non-integrated assemblies may be implemented combined into a single integrated assembly.

The scope of the invention should be construed on the basis of the claims appended to the description. The meaning and scope of the claims of the specification and modifications and variations derived from the idea equivalent to the claims must be included in the scope of the present invention.

Claims

An array element of types for use as an image sensor or a solar cell, comprising:

sub-elements each of which has two or more unit pixel elements arranged in the th direction, and

a sub-element switch that is turned on or off between the sub-elements to arrange two or more sub-elements in the second direction,

wherein the sub-elements include a photodetector driving a photocurrent induced by incident light on the gate to flow along a channel between the source and drain, and a unit pixel element including a th switch and a second switch, the th switch being wired between a source terminal of the photodetector and a th solar cell bus line and being turned on or off, the second switch being wired between a gate terminal of the photodetector and a second solar cell bus line and being turned on or off.
2. The array element of claim 1, wherein the subelement switch is wired between the second solar cell bus of the th subelement and the th solar cell bus of the second subelement.
3. The array element according to claim 1, further comprising a control section which generates respective control signals for said th switch and second switch in a plurality of said unit pixel elements.
4. The array element of claim 1, wherein the subelements arranged in the second orientation share th solar cell bus line and a second solar cell bus line.
An array element of types for use as an image sensor or a solar cell, comprising:

a sub-element in which two or more unit pixel elements are arranged in the th direction, and

a sub-element switch that is turned on or off between the sub-elements to arrange two or more sub-elements in a second direction,

wherein the sub-elements include a photodetector driving a photocurrent induced by incident light onto a gate electrode to flow along a channel between a source electrode and a drain electrode, a unit pixel element including an th switch and a second switch, the th switch being connected between a source terminal of the photodetector and a th solar cell bus line, the second switch being connected between a gate terminal of the photodetector and a second solar cell bus line, and a unit pixel output terminal being connected to the second solar cell bus line and charging the second solar cell bus line with the photocurrent by a voltage.
6. The array element of claim 5, wherein the subelement switch is wired between the second solar cell bus of the th subelement and the th solar cell bus of the second subelement.
7. The array element according to claim 5, further comprising a control section which generates respective control signals for an th switch and a second switch in a plurality of said unit pixel elements.
8. The array element of claim 5, wherein the subelements arranged in the second orientation share th solar cell bus line and a second solar cell bus line.
9. The array element of claim 5 wherein said th switch is wired and turned on or off between a gate terminal of said photodetector and said th solar cell bus.
10. An array element according to claim 5 wherein the second switch is wired between the source terminal of the photodetector and the second solar cell bus to output photocurrent to the pixel output terminal.
11. An array element according to claim 5 wherein the photodetector further comprises a third switch wired between the second switch and the pixel output terminal and switched on or off.
12. The array element of claim 5, wherein said photodetector further comprises a fourth switch wired and turned on or off between a reset terminal of said photodetector and said th solar cell bus.
13. The array element of claim 12, wherein the reset terminal is doped with a different impurity than the impurities doped at the source and drain.
An electronic device of the kind , for use as an image sensor or a solar cell, comprising:

an image sensor section including two or more unit pixels capable of functioning as solar cells according to a control signal; and

a processor generating a control signal and transmitting the control signal to the image sensor part,

wherein each unit pixel includes a photodetector that drives a photocurrent induced by incident light incident on the gate electrode to flow along a channel between the source and drain electrodes;

wherein each unit pixel further comprises:

a th switch, the th switch being wired between the source terminal of the photodetector and the th solar cell bus and being turned on or off, and

a second switch wired between the gate terminal of the photodetector and the second solar cell bus and turned on or off.
15. The electronic device according to claim 14, wherein the processor sends a control signal to the image sensor section when there is no event that the image sensor section functions as an image sensor.
16. The electronic device according to claim 14, further comprising a battery that obtains the electric power supply from the image sensor section that has been charged with electric power.
17. The electronic device according to claim 16, further comprising a power IC that obtains electric power supply from the image sensor section that has been charged with electric power or from the battery.
18. The electronic device of claim 14, further comprising an ambient light sensor that collects ambient light and then provides ambient light information to the processor when the intensity of the light exceeds a fixed value, causing the sensor to generate a control signal.