KR20220006451A - Light modulation element, beam steering device including the same, and electric device including beam steering device - Google Patents

Abstract

A light modulation element includes: a first contact layer; a second contact layer; an active layer which is provided between the first contact layer and the second contact layer; a first contact plug which is provided between the first contact layer and the active layer; and a second contact plug which is provided between the second contact layer and the active layer. The width of at least one of the first contact plug and the second contact plug is smaller than the width of the active layer.

Description

LIGHT MODULATION ELEMENT, BEAM STEERING DEVICE INCLUDING THE SAME, AND ELECTRIC DEVICE INCLUDING BEAM STEERING DEVICE

The present disclosure relates to a light modulation device, a beam deflecting device, and an electronic device.

A light modulation device that changes transmission/reflection, polarization, phase, intensity, path, etc. of incident light is utilized in various optical devices. In addition, in order to control the above-described properties of light in a desired manner in an optical device, light modulation elements having various structures have been proposed.

For example, a liquid crystal having optical anisotropy, a microelectromechanical system (MEMS) structure using micro-mechanical movement of a light blocking/reflecting element, etc. are widely used in general light modulation devices. These optical modulation devices have an operation response time of several μs or more due to the characteristics of their driving method. In addition, there is a method of modulating the phase of light using the interference of light bundles in the form of multiple pixels or waveguides using an optical phased array (OPA) method. At this time, the pixel or waveguide is electrically and thermally controlled to adjust the phase of light.

In the case of using the MEMS structure using mechanical movement, there is a problem in that the volume of the optical modulation device increases and the price increases. Furthermore, the application may be limited due to issues such as vibration.

In the control method in the OPA method, a driving pixel must be provided for each pixel or waveguide, and a driving driver for the pixel driver is required, so circuits and devices are complicated and process costs can increase.

Recently, there has been an attempt to apply a metasurface to an optical modulation device. A metasurface is a structure in which a value smaller than the wavelength of incident light is applied to thickness, pattern, or period. For example, an optical device using a tunable metasurface based on a semiconductor material having a variable optical property (eg, refractive index) and a multi-quantum well structure is used in various technical fields from optical communication to optical sensing. .

An object to be solved is to provide an optical modulation device that independently adjusts a gain and a phase of light.

SUMMARY OF THE INVENTION An object to be solved is to provide a beam deflector that independently adjusts a gain and a phase of light.

SUMMARY An object to be solved is to provide an electronic device including a beam deflector for independently adjusting a gain and a phase of light.

However, the problem to be solved is not limited to the above disclosure.

In one aspect, the light modulation device comprises: a first contact layer; a second contact layer; an active layer provided between the first contact layer and the second contact layer; a first contact plug provided between the first contact layer and the active layer; and a second contact plug provided between the second contact layer and the active layer, wherein a width of at least one of the first contact plug and the second contact plug is smaller than a width of the active layer. can be

The active layer includes a plurality of quantum dot layers stacked in a direction perpendicular to an upper surface of the first contact layer and a plurality of well layers respectively provided on the plurality of quantum dot layers, and the width of the active layer is equal to that of the active layer. A light modulation device may be provided that is smaller than a wavelength of incident light, and a bandgap energy of the plurality of quantum dot layers is smaller than a bandgap energy of the plurality of well layers.

a first insulating layer provided between the first contact layer and the active layer; and a second insulating layer provided between the second contact layer and the active layer, wherein the first insulating layer covers a side surface of the first contact plug, and the second insulating layer covers a side surface of the second contact plug can be covered

The first insulating layer and the second insulating layer may have a refractive index smaller than that of the first contact plug and the second contact plug, respectively.

a passivation film provided on the first contact layer; wherein the passivation film may cover side surfaces of the first contact layer, the first insulating film, the active layer, the second insulating film, and the second contact layer have.

The first insulating layer and the second insulating layer may include a first oxide, and the passivation layer may include an electrically insulating material different from the first oxide.

a first charge injection layer provided between the active layer and the first contact plug; and a second charge injection layer provided between the active layer and the second contact plug, wherein each of the first charge injection layer and the second charge injection layer comprises the first contact plug and the second contact plug. It may have a greater width than each of the plugs.

The first contact layer and the first charge injection layer include GaAs of a first conductivity type, and the second contact layer and the second charge injection layer contain GaAs of a second conductivity type different from the first conductivity type. The first contact plug may include AlGaAs of the first conductivity type, and the second contact plug may include AlGaAs of the second conductivity type.

The first contact layer, the first contact plug, and the first charge injection layer include Si of a first conductivity type, and the second contact layer, the second contact plug, and the second charge injection layer include: The first conductivity type may include Si of a second conductivity type different from that of the first conductivity type, the active layer may include intrinsic Si, and the plurality of quantum dot layers may include Ge.

Conductivity types of the first contact layer, the first contact plug, and the first charge injection layer are n-type, and the conductivity types of the second contact layer, the second contact plug, and the second charge injection layer are p-type, the active layer may be intrinsic, and a width of the first contact layer may be greater than a width of the second contact layer.

A p-type electrode provided on the second contact layer may be included.

Conductivity types of the first contact layer, the first contact plug, and the first charge injection layer are p-type, and the conductivity types of the second contact layer, the second contact plug, and the second charge injection layer are n-type, the active layer may be intrinsic, and a width of the first contact layer may be greater than a width of the second contact layer.

An n-type electrode provided on the second contact layer may be included.

Each of the plurality of quantum dot layers may include a plurality of quantum dot patterns.

Each of the plurality of quantum dot layers further includes a plurality of connection patterns respectively provided between the plurality of quantum dot patterns, wherein the plurality of quantum dot patterns are connected to each other by the plurality of connection patterns, and the plurality of connection patterns The patterns may have smaller thicknesses than the plurality of quantum dot patterns.

The active layer further includes a plurality of barrier layers, wherein the quantum dot layer and the well layer immediately adjacent to each other among the plurality of quantum dot layers and the plurality of well layers include a pair of barrier layers immediately adjacent to each other among the plurality of barrier layers can be placed between them.

The plurality of quantum dot layers may include intrinsic InAs, the plurality of well layers may include intrinsic InGaAs, and the plurality of barrier layers may include intrinsic GaAs.

The second contact layer may include: a heavily doped layer; and a lightly doped layer provided between the heavily doped layer and the second contact plug, wherein the heavily doped layer and the lightly doped layer have the same conductivity type, and the doping concentration of the heavily doped layer is the lightly doped layer. It may be higher than the doping concentration of the layer.

a substrate provided opposite to the first contact plug with respect to the first contact layer; and a reflective layer provided between the substrate and the first contact layer.

The reflective layer may include a distributed Bragg reflector (DBR) including a plurality of low refractive index layers and a plurality of high refractive index layers that are alternately stacked.

In one aspect, the first light modulation device; and a second light modulation element, wherein each of the first and second light modulation elements includes a first contact layer, a plurality of nanostructures provided on the first contact layer, and the plurality of nanostructures a plurality of second contact layers respectively provided on the plurality of nanostructures, and each of the plurality of nanostructures includes a first contact plug, an active layer provided on the first contact plug, and a second contact plug provided on the active layer The beam deflecting device may include, wherein a width of at least one of the first contact plug and the second contact plug is smaller than a width of the active layer.

a reference voltage is applied to the first contact layer of the first light modulation element and the first contact layer of the second light modulation element;

a first voltage is applied to the second contact layer of the first light modulation device;

A second voltage different from the first voltage may be applied to the second contact layer of the second light modulation device.

The first contact layer of the first light modulation device and the first contact layer of the second light modulation device may be connected to each other.

and a substrate provided opposite to the plurality of nanostructures of the first light modulation element with respect to the first contact layer of the first light modulation element, wherein the substrate comprises the first contact layer of the second light modulation element. 1 may extend over the contact layer.

The first contact layer of the first light modulation device and the first contact layer of the second light modulation device may be spaced apart from each other.

and a substrate provided opposite to the plurality of nanostructures of the first light modulation element with respect to the first contact layer of the first light modulation element, wherein the substrate comprises the first contact layer of the second light modulation element. 1 may extend over the contact layer.

A reference voltage is applied to the plurality of second contact layers of the first light modulation element and the plurality of second contact layers of the second light modulation element, and the first contact layer of the first light modulation element A first voltage may be applied to , and a second voltage different from the first voltage may be applied to the first contact layer of the second optical modulation device.

Each of the first light modulation element and the second light modulation element further includes: an electrode provided on the plurality of second contact layers, the electrode being electrically connected to the plurality of second contact layers can

The active layer includes a plurality of quantum dot layers stacked in a direction perpendicular to an upper surface of the first contact layer, and a plurality of well layers respectively provided on the plurality of quantum dot layers, and the width of the active layer is the nanostructures. may be smaller than a wavelength of light incident thereon, and a bandgap energy of the plurality of quantum dot layers may be smaller than a bandgap energy of the plurality of well layers.

Each of the plurality of nanostructures of the first light modulation device and the second light modulation device may include: a first insulating layer surrounding the first contact plug; It may further include a second insulating layer surrounding the second contact plug.

Each of the first light modulation element and the second light modulation element may further include: a passivation film provided on the first contact layer, wherein the passivation film may cover side surfaces of the nanostructures.

a substrate provided opposite to the plurality of nanostructures of the first light modulation device with respect to the first contact layer of the first light modulation device; and a reflective layer provided between the substrate and the first contact layer of the first light modulation device, wherein the substrate and the reflective layer may extend onto the first contact layer of the second light modulation device .

The reflective layer may include a distributed Bragg reflector including a plurality of low refractive index layers and a plurality of high refractive index layers that are alternately stacked.

Each of the plurality of nanostructures of the first light modulation device and the second light modulation device may include: a first charge injection layer provided between the active layer and the first contact plug; and a second charge injection layer provided between the active layer and the second contact plug, wherein each of the first charge injection layer and the second charge injection layer comprises the first contact plug and the second contact plug. It may have a greater width than each of the plugs.

In one aspect, the light source; a beam deflector for controlling a propagation direction of the light incident from the light source to direct the light toward a subject; a sensor for receiving the reflected light from the subject; and a processor that analyzes the light received by the sensor, wherein the beam deflecting device includes a first light modulation element and a second light modulation element, wherein each of the first and second light modulation elements comprises: , a first contact layer, a plurality of nanostructures provided on the first contact layer, and a plurality of second contact layers respectively provided on the plurality of nanostructures, each of the plurality of nanostructures a first contact plug, an active layer provided on the first contact plug, and a second contact plug provided on the active layer, wherein a width of at least one of the first contact plug and the second contact plug is An electronic device may be provided that is smaller than the width of the active layer.

The present disclosure may provide a light modulation device that independently adjusts a gain and a phase of light.

The present disclosure may provide a beam deflector that independently adjusts a gain and a phase of light.

The present disclosure may provide an electronic device including a beam deflector that independently adjusts a gain and a phase of light.

However, the effect of the invention is not limited to the above disclosure.

1 is a cross-sectional view of a light modulation device according to an exemplary embodiment.
2 is an example of an active layer.
3 is another example of an active layer.
4 is another example of an active layer.
5 is a graph illustrating characteristics of the light modulation device of FIG. 1 .
FIG. 6 schematically illustrates a process in which density inversion occurs in the light modulation device of FIG. 1 .
7 is a schematic diagram illustrating a process in which stimulated emission occurs in the light modulation device of FIG. 1 .
FIG. 8 is a schematic diagram illustrating a process of changing a refractive index in the light modulation device of FIG. 1 .
9 to 12 are cross-sectional views illustrating a method of manufacturing the light modulation device described with reference to FIGS. 1 to 4 .
13 is a cross-sectional view of a beam deflecting device according to an exemplary embodiment.
14 is a cross-sectional view of a semiconductor device including a beam deflecting device according to an exemplary embodiment.
15 is a cross-sectional view of a semiconductor device including a beam deflector according to an exemplary embodiment.
16 is a cross-sectional view of a light modulation device according to another exemplary embodiment.
17 is a cross-sectional view of a semiconductor device including a beam deflector according to an exemplary embodiment.
18 is a block diagram illustrating a schematic configuration of an electronic device according to an exemplary embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. The described embodiments are merely exemplary, and various modifications are possible from these embodiments. In the following drawings, the same reference numerals refer to the same components, and the size of each component in the drawings may be exaggerated for clarity and convenience of description.

Hereinafter, what is referred to as "upper" or "on" may include those directly above, below, left, and right in contact as well as above, below, left, and right in non-contact.

The singular expression includes the plural expression unless the context clearly dictates otherwise. Also, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless otherwise stated.

The use of the term “above” and similar referential terms may be used in both the singular and the plural.

In the present specification, when light is deflected in one direction, it may mean that the propagation direction of light has a new component in the one direction or has more components. For example, when light traveling in the first direction is deflected in the second direction, the light may travel in a direction in which the first direction and the second direction are combined.

1 is a cross-sectional view of a light modulation device according to an exemplary embodiment.

일 수 있다. Referring to FIG. 1 , the light modulation device 10 may include a first contact layer 100 , a second contact layer 500 , a nanostructure ST, a passivation layer 110 , and an electrode 600 . have. The first contact layer 100 may include a semiconductor material, for example, a group 4 semiconductor material (eg, Si) or a compound semiconductor material (eg, GaAs). The first contact layer 100 may have a first conductivity type, and the doping concentration of the first contact layer 100 is about

can be

The nanostructure ST may be provided on the first contact layer 100 , and the width of the nanostructure ST may be smaller than the width of the first contact layer 100 . The width of the nanostructure ST may be measured in a direction parallel to the upper surface 100u of the first contact layer 100 , and may be smaller than the wavelength of the incident light IL incident on the light modulation device 10 . can For example, the width of the nanostructure ST may be about 600 nanometers (nm) or less. The nanostructure ST includes a first insulating layer 210 , a first contact plug 220 , a first charge injection layer 230 , an active layer 300 , a second charge injection layer 410 , and a second insulating layer 420 . , and a second contact plug 430 .

The first insulating layer 210 may be provided on the first contact layer 100 . The first insulating layer 210 may include an electrically insulating material, for example, an oxide (eg, SiO _x or AlO _x ). The first insulating layer 210 may have a lower refractive index than that of the first contact layer 100 , the first contact plug 220 , and the first charge injection layer 230 . The first insulating layer 210 may include a first hole 210h penetrating through the first insulating layer 210 and exposing the first contact layer 100 .

일 수 있다. The first contact plug 220 may be provided in the first hole 210h and may fill the first hole 210h. As shown in the drawing, the width of the first contact plug 220 may be smaller than the width of the active layer 300 . The first contact plug 220 may be electrically connected to the first contact layer 100 . For example, the first contact plug 220 may pass through the first insulating layer 210 to directly contact the first contact layer 100 . The first contact plug 220 may include a semiconductor material, for example, a group 4 semiconductor material (eg, Si) or a compound semiconductor material (eg, Al _x Ga _1-x As). When the first contact plug 220 includes Al _x Ga _1-x As, x may be 0.8 to 0.98. For example, in GaAs containing Ga and As in a 1:1 ratio, 80 at% to 98 at% of Ga is replaced with Al, thereby forming _{Al x} Ga _{1-x As.} The first contact plug 220 may have a first conductivity type, and the doping concentration of the first contact plug 220 is about

can be

일 수 있다.The first charge injection layer 230 may extend on the first insulating layer 210 and be provided on the first contact plug 220 . The first charge injection layer 230 may include a semiconductor material, for example, a group 4 semiconductor material (eg, Si) or a compound semiconductor material (eg, GaAs). The first charge injection layer 230 may have a first conductivity type, and a doping concentration of the first charge injection layer 230 may be smaller than a doping concentration of the first contact plug 220 . For example, the doping concentration of the first charge injection layer 230 is about

can be

The active layer 300 may be provided on the first charge injection layer 230 , and the width of the active layer 300 may be smaller than the wavelength of the incident light IL. For example, the width of the active layer 300 may be less than or equal to about 600 nanometers (nm).

2 is an example of an active layer.

Referring to FIG. 2 , the active layer 300a according to an embodiment may include a plurality of barrier layers 310 , a plurality of well layers 330 , and a plurality of quantum dot layers. The barrier layers 310 may be stacked in a direction perpendicular to the top surface 100u of the first contact layer 100 , and may have a bandgap energy greater than that of the well layers 330 and the quantum dot layers. The barrier layers 310 may include a compound semiconductor material having an intrinsic conductivity type (eg, GaAs). The well layers 330 may be positioned between the barrier layers 310 and may have a bandgap energy greater than that of the quantum dot patterns 320 . Accordingly, electrons and holes in the well layers 330 may have quantized energy levels. The well layers 330 may include a compound semiconductor material having an intrinsic conductivity type. For example, when the barrier layers 310 include GaAs, the well layers 330 may include InGaAs.

Each of the quantum dot layers may include a plurality of quantum dot patterns 320 . The bandgap energy of the quantum dot patterns 320 may be substantially the same as the energy of the incident light IL. The quantum dot patterns 320 may include a compound semiconductor material having an intrinsic conductivity type. For example, when the barrier layers 310 include GaAs and the well layers 330 include InGaAs, the quantum dot patterns 320 may include InAs.

3 is another example of an active layer.

Referring to FIG. 3 , unlike the active layer 300a illustrated in FIG. 2 , the active layer 300b may not include well layers 330 in FIG. 2 . The active layer 300b of FIG. 3 may be a group 4 semiconductor material, for example, an active layer 300b based on Si.

The barrier layers 310 and the quantum dot patterns 320 may include a group 4 semiconductor material. For example, the barrier layers 310 may include Si and the quantum dot patterns 320 may include Ge.

4 is another example of an active layer.

Referring to FIG. 4 , unlike the active layers 300a and 300b illustrated in FIGS. 2 and 3 , the active layer 300c may further include a connection layer 322 . The connecting layer 322 is positioned between the quantum dot patterns 320 and may connect the quantum dot patterns 320 to each other. As illustrated, the connection layer 322 is positioned between the barrier layers 310 and the well layers 330 , and may include substantially the same material as the quantum dot patterns 320 . The connection layer 322 may include a semiconductor material having an intrinsic conductivity type. For example, when the quantum dot patterns 320 include InAs or Ge, the connection layer 332 may also include InAs or Ge.

일 수 있다.Referring to FIG. 1 , a second charge injection layer 410 may be provided on the active layer 300 . The second charge injection layer 410 may include a semiconductor material, for example, a group 4 semiconductor material (eg, Si) or a compound semiconductor material (eg, GaAs). The second charge injection layer 410 may have a second conductivity type different from the first conductivity type. The doping concentration of the second charge injection layer 410 may be less than that of the second contact plug 430 ,

can be

The second insulating layer 420 may be provided on the second charge injection layer 410 . A second insulating film 420 may be an electrically insulating material, e.g., oxide (SiOx or AlO _x). The second insulating layer 420 may include a second hole 420h penetrating through the second insulating layer 420 and exposing the second charge injection layer 410 .

일 수 있다. The second contact plug 430 may be provided in the second hole 420h and may fill the second hole 420h. The second contact plug 430 may pass through the second insulating layer 420 to be directly electrically connected to the second charge injection layer 410 . The second contact plug 430 may include a semiconductor material, for example, a group 4 semiconductor material (eg, Si) or a compound semiconductor material (eg, Al _x Ga _1-x As). When the second contact plug 430 includes Al _x Ga _1-x As, x may be 0.8 to 0.98. In GaAs containing Ga and As 1:1, 80 at% to 98 at% of Ga is substituted with Al to produce _{Al x} Ga _{1-x As.} The second contact plug 430 may have a second conductivity type, and the doping concentration of the second contact plug 430 is about

can be

이고, 고농도 도핑층(520)의 도핑 농도는 약

일 수 있다. The second contact layer 500 may be provided on the second contact plug 430 and may extend on the second insulating layer 420 . The second contact layer 500 may include a lightly doped layer 510 and a heavily doped layer 520 that are sequentially stacked. The lightly doped layer 510 and the heavily doped layer 520 may include substantially the same semiconductor material, for example, a Group 4 semiconductor material (eg, Si) or a compound semiconductor material (eg, GaAs). have. The lightly doped layer 510 and the heavily doped layer 520 may have a second conductivity type. The doping concentration of the lightly doped layer 510 is about

and the doping concentration of the heavily doped layer 520 is about

can be

The passivation layer 110 may be positioned on the first contact layer 100 and may cover side surfaces of the nanostructure ST. The passivation layer 110 may include an electrically insulating material, for example, SiOx.

The electrode 600 may be provided on the second contact layer 500 . The conductivity type of the electrode 600 may be determined according to the conductivity type of the second contact layer 500 . When the conductivity type of the second contact layer 500 is p-type (ie, when the second conductivity type is p-type), the electrode 600 may be a p-type electrode, for example, an ITO electrode. When the conductivity type of the second contact layer 500 is n-type (ie, when the second conductivity type is n-type), the electrode 600 may be an n-type electrode, for example, an electrode including gold (Au). have. When the electrode 600 includes gold (Au), the electrode 600 may be provided at a position deviated from the light path of the emitted light OL.

Hereinafter, the characteristics of the light modulation element 10 are described.

5 is a graph illustrating characteristics of the light modulation device of FIG. 1 .

Referring to FIG. 5 , the intensity of the emitted light OL output from the light modulation device 10 may gradually increase as the current I applied to the active layer 300 increases. However, the intensity of the emitted light OL may no longer increase at a current greater than or equal to the specific value Ia. The active layer 300 may have a saturation gain at an applied current above a predetermined value Ia, which will enter the ground state of the conduction band of the quantum dot pattern 320, which is directly involved in causing stimulated emission in the active layer 300. This may be because the number of possible electrons is limited. The refractive index of the active layer 300 and the phase p of the incident light IL may change even in a region in which the gain of the active layer 300 no longer increases, that is, in a region in which the intensity of the emitted light OL does not increase any more. have.

As described above, the optical modulation device 10 may continuously change the phase of incident light while having a saturation gain according to an applied current. The optical modulation device 10 may further include a processor (not shown) capable of independently controlling the gain and the refractive index, and by applying a current to the active layer 300 , the refractive index and the gain of the active layer 300 are independently controlled. can be adjusted The principle of independently controlling the gain and the refractive index of the optical modulation device 10 will be described later.

FIG. 6 schematically illustrates a process in which density inversion occurs in the light modulation device of FIG. 1 .

Referring to FIG. 6 , the bandgap energy Eb of the barrier layers a1 and a4 may be greater than the bandgap energy Ew of the well layer a2 . The bandgap energy Ew of the well layer a2 may be greater than the bandgap energy Ed of the quantum dot pattern a3.

By the current applied to the active layer 300 , electrons staying in the valance band of the quantum dot pattern a3 may obtain energy and move to the conduction band. For example, electrons staying in the valence band of the quantum dot pattern a3 may obtain energy and be filled in the ground state S1 of the conduction band. When a current equal to the band gap energy Ed of the quantum dot pattern a3 is applied to the active layer 300 , the electrons in the valence band of the quantum dot pattern a3 gain energy and move to the conduction band. When an electric current is continuously applied, a greater number of electrons can move, and thus more density reversal can occur.

7 schematically illustrates a process in which stimulated emission occurs in an optical modulation device.

Referring to FIG. 7 , when incident light IL of a wavelength having the same energy as the band gap energy of the quantum dot pattern a3 in which the density inversion occurs is incident on the light modulation device 10 , stimulated emission occurs while The intensity of the incident light IL may be amplified. Accordingly, the emitted light OL having a stronger intensity than that of the incident light IL may be output from the light modulation device 10 . Stimulated emission may occur by electrons filled in the ground state S1 of the conduction band of the quantum dot pattern a3. Since the number of electrons that can be filled in the ground state S1 is limited, even if a current is continuously applied to the active layer 300 , stimulated emission may no longer increase. Accordingly, the amplification factor of the incident light IL may also be saturated without becoming greater than a specific value. In other words. The active layer 300 may have a saturation gain when a current greater than or equal to a specific value is applied.

8 is a schematic diagram illustrating a process of changing a refractive index in a light modulation device.

Referring to FIG. 8 , electrons may be filled in a plurality of quantized states of the quantum dot pattern a3 and the well layer a2 while the amount of current applied to the active layer 300 increases. Even after all electrons are filled in the plurality of states of the quantum dot pattern a3 , if current is continuously applied to the active layer 300 , electrons are continuously filled in the plurality of states of the well layer a2 , and the refractive index of the active layer 300 . This can change. As described above, the gain of the active layer 300 may be saturated without further increasing even if the applied current value increases above a specific value, but even in a state in which the gain of the active layer 300 is saturated, the active layer 300 The refractive index of can be continuously changed as current is continuously applied. As such, by applying a current to the active layer 300 , the gain and phase of light may be independently controlled.

The present disclosure may provide a transmissive light modulation device 10 that independently adjusts a gain and a phase of light.

9 to 12 are cross-sectional views illustrating a method of manufacturing the light modulation device described with reference to FIGS. 1 to 4 . For brevity of the description, descriptions of contents substantially the same as those described with reference to FIGS. 1 to 4 will be omitted.

Referring to FIG. 9 , a preliminary first contact plug layer 220P, a preliminary first charge injection layer 230P, a preliminary active layer 300P, and a preliminary second charge injection layer 410P are formed on the first contact layer 100 . , a second preliminary contact plug layer 430P, and a preliminary second contact layer 500P may be formed. The preliminary active layer 300P may include a plurality of preliminary barrier layers, a plurality of preliminary well layers, and a plurality of preliminary quantum dot layers. The preliminary second contact layer 500P may include a preliminary lightly doped layer 510P and a preliminary high concentration doped layer 520P that are sequentially stacked on the preliminary second contact plug layer 430P. The first contact layer 100 , the preliminary first contact plug layer 220P, the preliminary first charge injection layer 230P, the preliminary active layer 300P, the preliminary second charge injection layer 410P, and the preliminary second contact plug layer The first contact plug 220 , the first charge injection layer 230 , the active layer 300 , and the second charge described with reference to FIGS. 1 to 4 , respectively, are the 430P and the preliminary second contact layer 500P. The injection layer 410 , the second contact plug 430 , and the second contact layer 500 may include substantially the same material.

First preliminary contact plug layer 220P, preliminary first charge injection layer 230P, preliminary active layer 300P, preliminary second charge injection layer 410P, preliminary second contact plug layer 430P, and preliminary second The contact layer 500P may be formed by sequentially depositing materials included in each layer on the first contact layer 100 . The deposition process, for example, a chemical vapor deposition (Chemical Vapor Deposition, hereinafter, CVD) process, a physical vapor deposition (Physical Vapor Deposition, hereinafter, PVD) process, or an atomic layer deposition (Atomic Layer Deposition, hereinafter, ALD) process may include In addition, the preliminary first contact plug layer 220P, the preliminary first charge injection layer 230P, the preliminary active layer 300P, the preliminary second charge injection layer 410P, the preliminary second contact plug layer 430P, and the preliminary The second contact layer 500P may be formed by an epitaxial growth process, for example, a Molecular Beam Epitaxy (MBE) process or a Metal Organic Chemical Vapor Deposition (MOCVD) process. have.

Referring to FIG. 10 , a first preliminary contact plug layer 220P, a preliminary first charge injection layer 230P, a preliminary active layer 300P, a second preliminary charge injection layer 410P, and a second preliminary contact plug layer 430P. ), and the preliminary second contact layer 500P may be patterned until the first contact layer 100 is exposed by an anisotropic etching process using an etch mask provided on the preliminary second contact layer 500P. The etch mask may be removed during or after the etch process. A first contact plug 220 , a first charge injection layer 230 , an active layer 300 , a second charge injection layer 410 , and a second contact plug ( 430) may be formed.

Referring to FIG. 11 , an oxidation process is performed on the first contact plug 220 and the second contact plug 430 , and the first insulating layer 210 and the second contact plug 210 surrounding the first contact plug 220 and the second contact plug 430 are oxidized. A second insulating layer 420 surrounding the 430 may be formed. When the first contact plug 220 and the second contact plug 430 include Si or AlGaAs, the first insulating layer 210 and the second insulating layer 420 may include SiO _x or AlO _x .

Referring to FIG. 12 , the passivation layer 110 described with reference to FIGS. 1 to 4 may be formed on the first contact layer 100 . The passivation layer 110 may be formed by depositing an _{electrical insulating material (eg, SiO x} ) on the first contact layer 100 exposed by the patterning process described with reference to FIG. 9 . The deposition process may include, for example, a chemical vapor deposition (CVD) process, a physical vapor deposition (PVD) process, or an atomic layer deposition (ALD) process. In addition, the passivation film 110 may be formed by an epitaxial growth process, for example, a molecular beam epitaxy (MBE) process or a metal organic chemical vapor deposition (MOCVD) process.

Referring back to FIG. 1 , the electrode 600 may be formed by a deposition process performed on the second contact layer 500 . For example, when the conductivity type of the second contact layer 500 is p-type or n-type, an ITO electrode or a gold (Au) electrode may be deposited on the second contact layer 500 .

13 is a cross-sectional view of a beam deflecting device according to an exemplary embodiment. For brevity of the description, descriptions of contents substantially the same as those described with reference to FIGS. 1 to 4 will be omitted.

Referring to FIG. 13 , a beam including a first contact layer 100 , a plurality of nanostructures ST, second contact layers 500 , a passivation layer 110 , and a plurality of electrodes 600 . A deflection device 20 may be provided. The conductivity type of the first contact layer 100 may be n-type, and a reference voltage (or a ground voltage) may be applied to the first contact layer 100 .

The nanostructures ST may be arranged in a first direction DR1 parallel to the top surface 100u of the first contact layer 100 . The conductivity types of the first contact plug 220 and the first charge injection layer 230 of the nanostructures ST may be n-type, and the conductivity of the second charge injection layer 410 and the second contact plug 430 of the nanostructures ST. The type may be p-type.

The second contact layers 500 may be respectively provided on the nanostructures ST. Each of the second contact layers 500 may be sequentially stacked and include a lightly doped layer and a heavily doped layer having a p-type conductivity.

The passivation layer 110 described with reference to FIGS. 1 to 4 may be provided between the nanostructures ST.

The electrodes 600 may be provided on the second contact layers 500 and the passivation layer 110 , and each of the electrodes 600 may correspond to a portion of the second contact layers 500 . Although each of the electrodes 600 is illustrated as corresponding to three second contact layers 500 , this is exemplary, and the number of second contact layers 500 corresponding to each of the electrodes 600 is required. can be determined according to The electrodes 600 may be electrically connected to the corresponding second contact layers 500 . For example, the electrodes 600 may directly contact heavily doped layers of the corresponding second contact layers 500 . Different voltages, for example, a first voltage V1 , a second voltage V2 , and a third voltage V3 may be applied to the electrodes 600 .

The beam deflector 20 may include light modulation groups G1 , G2 , and G3 . One light modulation group may include a plurality of light modulation elements having the same degree of light amplification and phase modulation of the incident light IL. For example, a first light modulation group G1 , a second light modulation group G2 , and a third light modulation group G3 are illustrated.

Control elements (not shown) for controlling each of the light modulation groups G1 , G2 , and G3 on the first contact layer 100 , for example, a thin film transistor for controlling a voltage applied to the electrodes 600 . can be provided. Control elements may be provided between the light modulation groups.

The incident light IL incident on the beam deflector 20 may be provided to different light modulation groups G1 , G2 , and G3 and may be modulated differently by the light modulation groups G1 , G2 , and G3 . Accordingly, the emitted light OL includes portions having different phases and may be deflected in a direction different from that of the incident light IL.

The present disclosure may provide a transmissive beam deflecting device 20 including light modulation groups G1 , G2 , and G3 for independently adjusting a gain and a phase of light.

14 is a cross-sectional view of a semiconductor device including a beam deflector according to an exemplary embodiment. For brevity of description, the same content as that described with reference to FIG. 13 will be omitted.

The embodiment of FIG. 14 may further include the substrate 1000 in addition to the embodiment of FIG. 13 . The substrate 1000 may be provided on the opposite side of the nanostructures ST in contact with the first contact layer 100 , and may be a semiconductor device layer that controls the beam deflector 21 . The substrate 1000 may include wirings, electronic devices, and insulating layers, and the electronic devices may control the light modulation groups G1 , G2 , and G3 , respectively. The substrate 1000 may include a seed layer for growing the first contact layer 100 .

15 is a cross-sectional view of a semiconductor device including a beam deflector according to an exemplary embodiment. For brevity of description, the same content as that described with reference to FIG. 14 will be omitted.

Referring to FIG. 15 , the first contact layers 102 may be arranged to be spaced apart from each other in a first direction DR1 parallel to the upper surface of the substrate 1000 . Each of the first contact layers 102 may be substantially the same as the first contact layer 100 described with reference to FIG. 1 .

Some of the nanostructures ST may be provided on each of the first contact layers 102 . 15 illustrates an example in which three nanostructures ST are provided on one first contact layer 102 , but this is exemplary.

The passivation layer 110 may be provided between the nanostructures ST and may fill a region between the first contact layers 102 . The passivation film 110 may be substantially the same as the passivation film 110 described with reference to FIGS. 1 to 4 .

The electrode 602 may be provided on the second contact layers 500 and the passivation layer 110 , and may correspond to all of the second contact layers 500 . The electrode 602 may be an n-type electrode, for example, a gold (Au) electrode. The electrode 602 may be electrically connected to the second contact layers 500 , and, for example, may directly contact heavily doped layers of the second contact layers 500 .

A reference voltage (or ground voltage) may be applied to the electrode 602 . Different voltages, for example, the first to third voltages V1 , V2 , and V3 described with reference to FIG. 13 may be applied to the first contact layers 102 . Accordingly, the light modulation groups G1 , G2 , and G3 of the beam deflector 22 may be respectively defined by the first contact layers 102 .

16 is a cross-sectional view of a light modulation device according to another exemplary embodiment. For brevity of description, the same content as those described with reference to FIGS. 1 to 4 will be omitted.

The embodiment of FIG. 16 further includes a substrate 1000 and a reflective layer 2000 in addition to the embodiment of FIG. 1 . The substrate 1000 is a semiconductor device layer that controls the light modulation device 11 , and may be a layer including wirings, electronic devices, and insulating layers.

The reflective layer 2000 may be provided on the opposite side of the nanostructure ST in contact with the first contact layer 100 . The reflective layer 2000 may include a distributed Bragg reflector including a plurality of low refractive index layers and a plurality of high refractive index layers that are alternately stacked. Light incident on the diffuse Bragg reflector may be reflected at the boundaries of the low refractive index layers and the high refractive index layers. The thicknesses of the low refractive index layers and the thicknesses of the high refractive index layers may be determined such that constructive interference occurs between the reflected lights. For example, the reflective layer 2000 may include a plurality of AlAs layers and a plurality of Al _0.5 Ga _0.5 As layers that are alternately stacked, or a plurality of Al _0.9 Ga _0.1 As layers and Al _0.3 Ga _0.7 As layers that are alternately stacked. may include

17 is a cross-sectional view of a semiconductor device including a beam deflecting device according to an exemplary embodiment.

18 is a block diagram illustrating a schematic configuration of an electronic device according to an exemplary embodiment.

Referring to FIG. 18 , the electronic device 3000 includes a lighting device 3100 that irradiates light toward a subject OBJ, a sensor 3300 that receives light reflected from the subject OBJ, and the sensor 3300 receives light. The processor 3200 may include a processor 3200 that performs an operation for obtaining information on the subject OBJ from one light. The electronic device 3000 may also include a memory 3400 in which codes or data for execution of the processor 3200 are stored.

The lighting device 3100 may include a light source 3120 and a beam deflector 3110 . The light source 3120 may generate a source light for scanning the subject OBJ, for example, a pulse laser. The beam deflector 3110 illuminates the subject OBJ by changing the propagation direction of light from the light source 3120 , and the beam deflectors 20 , 21 , and 22 of FIGS. 13 , 14 , 15 , and 17 . , 23) may include any one of.

Between the lighting device 3100 and the subject OBJ, a direction of the light from the lighting device 3100 to be directed toward the object OBJ may be adjusted, or optical elements for additional modulation may be further disposed.

_{The sensor 3300 may sense the light L r} reflected by the subject OBJ, and may include an array of light detection elements. The sensor 3300 may further include a spectrometer for analyzing the light reflected from the subject OBJ for each wavelength.

The processor 3200 may perform an operation for obtaining information on the subject OBJ from the light received by the sensor 3300 , and may oversee processing and control of the entire electronic device 3000 . The processor 3200 may acquire and process information about the subject OBJ, for example, 2D or 3D image information. In addition, the processor 3200 may generally control driving of a light source included in the lighting device 3100 or operation of the sensor 3300 , for example, applied to a light modulation device included in the lighting device 3100 . The current value can be calculated. The processor 3200 may also determine whether to authenticate the user based on information obtained from the subject OBJ, and may execute other applications.

Code for execution by the processor 3200 may be stored in the memory 3400 . In addition to the memory 3400 , various execution modules executed by the electronic device 3000 , data therefor, for example, a program code used by the processor 3200 for an operation for obtaining information on the subject OBJ, and Codes such as an application module that can be executed by utilizing the information of the subject OBJ may be stored. In addition, as a device that may be additionally provided in the electronic device 3000 and a program for driving the device, a communication module, a camera module, a video playback module, an audio playback module, and the like may be further stored.

The operation result of the processor 3200 , that is, information on the shape and location of the object OBJ may be transmitted to another device or unit as needed. For example, other electronic devices or units (eg, display devices, printers, smartphones, mobile phones, personal digital assistants (PDAs), laptops, PCs, and various wearable devices that use information about the subject OBJ) Information on the object OBJ may be transmitted to a control unit of a wearable device or other mobile or non-mobile computing device. The memory 3400 may be a flash memory type or a hard disk type. type), multimedia card micro type, card type memory (such as SD or XD memory), RAM (Random Access Memory), SRAM (Static Random Access Memory), ROM (ROM, It may be a read-only memory), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a magnetic disk, an optical disk, or the like.

The electronic device 3000 is, for example, a portable mobile communication device, a smart phone, a smart watch, a personal digital assistant (PDA), a laptop, a PC, or other mobile or non-mobile computing. It may be a device, an autonomous vehicle, an autonomous vehicle, a robot, a self-driving device such as a drone, or an Internet of Things device.

The above description provides examples for explaining the technical idea of the present disclosure. The technical spirit of the present disclosure is not limited to the above embodiments, and it is clear that various modifications and changes are possible by those skilled in the art.

100, 102: first contact layer 110: passivation film
210: first insulating layer 220: first contact plug
230: first charge injection layer 300: active layer
310: barrier layer 320: quantum dot pattern
322: connecting film 330: well layer
410: second charge injection layer 420: second insulating film
430: second contact plug 500: second contact layer
600: electrode

Claims (34)

a first contact layer;
a second contact layer;
an active layer provided between the first contact layer and the second contact layer;
a first contact plug provided between the first contact layer and the active layer; and
a second contact plug provided between the second contact layer and the active layer;
A width of at least one of the first contact plug and the second contact plug is smaller than a width of the active layer. The method of claim 1,
The active layer includes a plurality of quantum dot layers stacked in a direction perpendicular to an upper surface of the first contact layer, and a plurality of well layers respectively provided on the plurality of quantum dot layers,
The width of the active layer is smaller than the wavelength of light incident on the active layer,
A bandgap energy of the plurality of quantum dot layers is less than a bandgap energy of the plurality of well layers. The method of claim 1,
a first insulating layer provided between the first contact layer and the active layer; and
a second insulating film provided between the second contact layer and the active layer;
the first insulating layer covers a side surface of the first contact plug;
The second insulating layer covers a side surface of the second contact plug. 4. The method of claim 3,
The first insulating layer and the second insulating layer have refractive indices smaller than those of the first contact plug and the second contact plug, respectively. 4. The method of claim 3,
A passivation film provided on the first contact layer; further comprising
The passivation layer may cover side surfaces of the first contact layer, the first insulating layer, the active layer, the second insulating layer, and the second contact layer. 6. The method of claim 5,
The first insulating film and the second insulating film include a first oxide,
and the passivation layer includes an electrically insulating material different from the first oxide. The method of claim 1,
a first charge injection layer provided between the active layer and the first contact plug; and
a second charge injection layer provided between the active layer and the second contact plug;
Each of the first charge injection layer and the second charge injection layer has a width greater than that of each of the first contact plug and the second contact plug. 8. The method of claim 7,
The first contact layer and the first charge injection layer include GaAs of a first conductivity type;
the second contact layer and the second charge injection layer include GaAs of a second conductivity type different from the first conductivity type;
the first contact plug includes AlGaAs of the first conductivity type;
and the second contact plug includes AlGaAs of the second conductivity type. 8. The method of claim 7,
the first contact layer, the first contact plug, and the first charge injection layer include Si of a first conductivity type;
the second contact layer, the second contact plug, and the second charge injection layer include Si of a second conductivity type different from the first conductivity type;
The active layer comprises intrinsic Si,
The plurality of quantum dot layers include Ge. 8. The method of claim 7,
Conductivity types of the first contact layer, the first contact plug, and the first charge injection layer are n-type;
Conductivity types of the second contact layer, the second contact plug, and the second charge injection layer are p-type;
the active layer is intrinsic,
A width of the first contact layer is greater than a width of the second contact layer. 11. The method of claim 10,
The light modulation device further comprising a p-type electrode provided on the second contact layer. 8. The method of claim 7,
Conductivity types of the first contact layer, the first contact plug, and the first charge injection layer are p-type;
Conductivity types of the second contact layer, the second contact plug, and the second charge injection layer are n-type;
the active layer is intrinsic,
A width of the first contact layer is greater than a width of the second contact layer. 8. The method of claim 7,
The light modulation device further comprising an n-type electrode provided on the second contact layer. The method of claim 1,
Each of the plurality of quantum dot layers is a light modulation device including a plurality of quantum dot patterns. The method of claim 1,
The active layer further comprises a plurality of barrier layers,
The quantum dot layer and the well layer immediately adjacent to each other among the plurality of quantum dot layers and the plurality of well layers are disposed between a pair of barrier layers immediately adjacent to each other among the plurality of barrier layers. 16. The method of claim 15,
wherein the plurality of quantum dot layers include intrinsic InAs;
wherein the plurality of well layers include intrinsic InGaAs;
wherein the plurality of barrier layers include intrinsic GaAs. The method of claim 1,
The second contact layer includes:
heavily doped layer; and
a lightly doped layer provided between the heavily doped layer and the second contact plug;
The heavily doped layer and the lightly doped layer have the same conductivity type,
A doping concentration of the heavily doped layer is higher than that of the lightly doped layer. The method of claim 1,
a substrate provided opposite to the first contact plug with respect to the first contact layer; and
and a reflective layer provided between the substrate and the first contact layer. 19. The method of claim 18,
The reflective layer includes a distributed Bragg reflector (DBR) including a plurality of low-refractive-index layers and a plurality of high-refractive-index layers that are alternately stacked. a first light modulation element; and
a second light modulation device; including,
Each of the first and second light modulation devices includes a first contact layer, a plurality of nanostructures provided on the first contact layer, and a plurality of second contacts respectively provided on the plurality of nanostructures. including layers,
Each of the plurality of nanostructures includes a first contact plug, an active layer provided on the first contact plug, and a second contact plug provided on the active layer,
A width of at least one of the first contact plug and the second contact plug is smaller than a width of the active layer. 21. The method of claim 20,
a reference voltage is applied to the first contact layer of the first light modulation element and the first contact layer of the second light modulation element;
a first voltage is applied to the second contact layer of the first light modulation device;
and a second voltage different from the first voltage is applied to the second contact layer of the second light modulation device. 21. The method of claim 20,
The first contact layer of the first light modulation element and the first contact layer of the second light modulation element are connected to each other. 23. The method of claim 22,
Further comprising; a substrate provided on the opposite side of the plurality of nanostructures of the first light modulation device with respect to the first contact layer of the first light modulation device;
and the substrate extends onto the first contact layer of the second light modulation element. 21. The method of claim 20,
The first contact layer of the first light modulation element and the first contact layer of the second light modulation element are spaced apart from each other. 25. The method of claim 24,
Further comprising; a substrate provided on the opposite side of the plurality of nanostructures of the first light modulation device with respect to the first contact layer of the first light modulation device;
and the substrate extends onto the first contact layer of the second light modulation element. 25. The method of claim 24,
a reference voltage is applied to the plurality of second contact layers of the first light modulation device and the plurality of second contact layers of the second light modulation device;
a first voltage is applied to the first contact layer of the first light modulation device;
A second voltage different from the first voltage is applied to the first contact layer of the second light modulation device. 21. The method of claim 20,
Each of the first light modulation element and the second light modulation element comprises:
Further comprising an electrode provided on the plurality of second contact layers,
wherein the electrode is electrically connected to the plurality of second contact layers. 21. The method of claim 20,
The active layer includes a plurality of quantum dot layers stacked in a direction perpendicular to an upper surface of the first contact layer and a plurality of well layers respectively provided on the plurality of quantum dot layers,
The width of the active layer is smaller than the wavelength of light incident on the nanostructures,
a bandgap energy of the plurality of quantum dot layers is less than a bandgap energy of the plurality of well layers. 21. The method of claim 20,
Each of the plurality of nanostructures of the first light modulation device and the second light modulation device includes:
a first insulating layer surrounding the first contact plug;
and a second insulating layer surrounding the second contact plug. 30. The method of claim 29,
Each of the first light modulation element and the second light modulation element comprises:
A passivation film provided on the first contact layer; further comprising
The passivation layer is a beam deflector that covers side surfaces of the nanostructures. 31. The method of claim 30,
a substrate provided opposite to the plurality of nanostructures of the first light modulation device with respect to the first contact layer of the first light modulation device; and
a reflective layer provided between the substrate and the first contact layer of the first light modulation device;
and the substrate and the reflective layer extend onto the first contact layer of the second light modulation element. 32. The method of claim 31,
The reflective layer includes a distributed Bragg reflector including a plurality of low-refractive-index layers and a plurality of high-refractive-index layers that are alternately stacked. 21. The method of claim 20,
Each of the plurality of nanostructures of the first light modulation device and the second light modulation device includes:
a first charge injection layer provided between the active layer and the first contact plug; and
a second charge injection layer provided between the active layer and the second contact plug;
Each of the first charge injection layer and the second charge injection layer has a width greater than a width of each of the first contact plug and the second contact plug. light source;
a beam deflector for controlling a propagation direction of the light incident from the light source to direct the light toward a subject;
a sensor for receiving the reflected light from the subject; and
A processor that analyzes the light received by the sensor; including,
The beam deflecting device includes a first light modulation element and a second light modulation element,
Each of the first and second light modulation devices includes a first contact layer, a plurality of nanostructures provided on the first contact layer, and a plurality of second contacts respectively provided on the plurality of nanostructures. including layers,
Each of the plurality of nanostructures includes a first contact plug, an active layer provided on the first contact plug, and a second contact plug provided on the active layer,
A width of at least one of the first contact plug and the second contact plug is smaller than a width of the active layer.

Images