WO2018209654A1 - Monochromatic light wavelenth recognition device, system and method - Google Patents

Abstract

A monochromatic light wavelength recognizing device, system and method. The monochromatic light wavelength recognition device comprises: an electrically conductive substrate (10); an insulation layer (20) formed on the electrically conductive substrate (10); and a thermoelectronic emission layer (30), made of a metallic material and formed on the insulation layer (20); the Fermi level of the conductivity band of the insulation layer (20) is higher than that of the metallic material of the thermoelectronic emission layer (30). The present invention provides, on the basis of new thermoelectron energy distribution principles, an unprecedented monochromatic light wavelength recognition device structure; said device structure is a thermoelectronic emission layer (30) - insulation layer (20) - electrically conductive substrate (10) (EIC) structure, which overcomes the limitation of thermoelectron scattering, is not affected by the scattering of the thermoelectrons in the whole insulation layer (20), and only depends on the behavior of the thermoelectrons at the interface between the thermoelectronic emission layer (30) and the insulation layer (20). Therefore, the thickness of the insulation layer (20) can reach tens of nanometers, thereby avoiding the electric leakage of the insulation layer (20), ensuring the reliability of the whole device.

Description

Monolithic optical wavelength recognition device, system and method Technical field

The present disclosure relates to the field of photodetection technology, and in particular, to a device, system and method for monochromatic optical wavelength identification.

Background technique

Monochromatic light wavelength recognition is widely used in communications, imaging, image recognition, tunable lasers, missile tracking and other fields. Due to the limitation of the carrier relaxation mechanism, the conventional semiconductor photodetector itself does not have the wavelength recognition capability. In order to achieve wavelength recognition, conventional semiconductor photodetectors require auxiliary elements with wavelength selectivity, such as gratings (see Reference 1), single mode fibers (see Reference 2), Bragg mirrors (see Reference 3), or resonances. Cavity (see Reference 4) and so on. However, these wavelength recognition devices are complex, space-consuming, costly, and difficult to integrate with high density.

In order to simplify the system, a thermoelectric photodetector capable of performing monochromatic wavelength recognition without the aid of an auxiliary component has been reported (see Reference 5). This thermal electron photodetector has a metal-insulator-metal (MIM) structure that uses the hot electrons generated by the metal to replace the electron-hole pairs generated by the semiconductor for wavelength recognition. When light is irradiated from the top to the bottom of the sample, hot electrons are generated in the upper metal and pass over the conduction band of the insulating layer into the underlying metal, causing an increase in the potential of the underlying metal to form an open circuit voltage. In the case where the hot electrons are not scattered by the insulating layer, the incident light wavelength has a one-to-one correspondence with the open circuit voltage value. The shorter the incident light wavelength, the higher the photon energy and the larger the open circuit voltage, so the monochromatic light wavelength can be read by reading. Take the open circuit voltage of the device. However, the open circuit voltage must be generated in a very thin thickness of the intermediate insulating layer, generally less than 10 nm, so as to ensure that the hot electrons can pass through the insulating layer without entering the underlying metal to form an open circuit voltage without applying an external voltage. As the thickness of the insulating layer increases, the thermal electrons undergo strong scattering as they pass through the insulating layer. The thermal electron energy is lost and cannot reach the underlying metal. The open circuit voltage disappears and the wavelength identification also fails. In general, the average free path of hot electrons in the insulating layer is less than 10 nm. Therefore, devices using the MIM structure open circuit voltage for monochromatic optical wavelength identification cannot achieve an intermediate insulating layer thickness exceeding 10 nm, and an excessively thin intermediate insulating layer. It will cause very serious device leakage and reliability problems, and it is difficult to put it into practical use.

Reference 1: Chen E, Chou SY. Wavelength detector using a pair of Metal-semiconductor-metal photodetectors with subwavelength finger spacings. Electronics Letters 32, 1510-1511 (1996).; 2. Kersey AD, et al. Fiber gratings. Journal of Lightwave Technology 15, 1442-1463 (1997).

Reference 2: Wang Q, Farrell G, Freir T, Rajan G, Wang PF. Low-cost wavelength measurement based on a macrobending single-mode fiber. Optics Letters 31, 1785-1787 (2006)

Reference 3: Nabiev R, ChangHasnain CJ, Eng LE, Lau KY, Ieee. Spectrodetector-Novel monolithic wavelength reader and photodetector. Leos'95-Ieee Lasers and Electro-Optics Society 1995 Annual Meeting-8th Annual Meeting Conference Proceedings, Vols 1&2, A21-A22 (1995).

Reference 4: Kung HL, et al. Wavelength monitor based on two single-quantum-well absorbers sampling a standing wave pattern. Applied Physics Letters 76, 3185-3187 (2000).

Reference 5: Wang F, Melosh NA. Power-independent wavelength determination by hot carrier collection in metal-insulator metal devices. Nature Communications 4, 1711 (2013).

Public content

(1) Technical problems to be solved

In order to at least partially address the above problems, the present disclosure provides a device, system and method for monochromatic optical wavelength identification.

(2) Technical plan

According to an aspect of the present disclosure, there is provided a monochromatic light wavelength identifying device comprising: a conductive substrate; an insulating layer formed on the conductive substrate; and a thermal electron emission layer formed of a metallic material on the insulating layer Wherein the conduction band of the insulating layer is higher than the Fermi level of the metallic material of the thermal electron emission layer.

In some embodiments of the present disclosure, the thermal electron emission layer is a film having a thickness of between 1 nm and 50 nm formed of a metal thin film or a compound having a metallic property.

In some embodiments of the present disclosure, the metal is a composite material of one or more of the following materials: gold, silver, aluminum, copper, platinum, titanium, nickel; the metal compound is One of the following materials: ThO ₂ , La ₂ O ₃ , CeO ₂ , Y ₂ O ₃ , LaB ₆ .

In some embodiments of the present disclosure, the insulating layer is an inorganic insulating film or an organic insulating film having a thickness of between 5 nm and 1000 nm.

In some embodiments of the present disclosure, the material forming the organic insulating film is PMMA; the material forming the inorganic insulating film is one or more of the following materials: Al ₂ O ₃ , SiN _x , Ta _{2 O 5, HfO 2, Ga 2} O 3.

In some embodiments of the present disclosure, the conductive substrate is a bulk substrate of a conductive material; or comprises: a substrate body and a thin film of conductive material formed on the substrate body.

In some embodiments of the present disclosure, the conductive material is: a metal whose work function is greater than or equal to a work function of the thermal electron emission layer; or a resistivity of <10 Ω·cm, and a work function greater than that of the thermal electron emission layer Doped semiconductor material of work function.

In some embodiments of the present disclosure, the conductive substrate is a p-type doped Si substrate; the insulating layer is a SiO ₂ film formed on the p-type doped Si substrate; the thermionic emission layer is An aluminum layer formed on the SiO ₂ film.

In some embodiments of the present disclosure, the method further includes: a first electrode electrically connected to the conductive substrate; and a second electrode electrically connected to the thermal electron emission layer.

In some embodiments of the present disclosure, the conductive substrate is a bulk substrate of a conductive material, the first electrode and the insulating layer are formed on the same surface or different surfaces of the conductive substrate; or the conductive substrate includes: a substrate body and formation A film of a conductive material on the substrate body, the first electrode and the insulating layer are both formed on the film of the conductive material.

According to another aspect of the present disclosure, there is also provided a monochromatic optical wavelength identification system comprising: a measurement loop comprising: a monochromatic optical wavelength identification device connected in series and forming a loop, a bias supply device, and a photocurrent measurement device The monochromatic light wavelength identifying device is a monochromatic light wavelength identifying device as described above.

In some embodiments of the present disclosure, the method further includes: a control processing module, configured to: control the bias supply device to provide a bias voltage to the monochromatic optical wavelength identification device and record the loop measured by the photocurrent measurement device Current; calculate the current ratio of the current values corresponding to the two different bias voltages, and compare the current ratio with the ratio of the different optical wavelengths in the same environment to obtain the wavelength of the monochromatic light to be calibrated.

In some embodiments of the present disclosure, the control processing module stores a relationship between a monochromatic light wavelength and a corresponding current ratio.

According to another aspect of the present disclosure, a method of identifying a monochromatic light wavelength is also provided. The monochromatic light wavelength identification method is based on the monochromatic light wavelength identification system as described above, comprising: receiving a monochromatic light irradiation to be calibrated by a thermal electron emission layer of a monochromatic light wavelength identification device; and a thermal electron emission layer and a conductive substrate A negative voltage V _a is applied therebetween to obtain a photocurrent value I _a in the loop; _a negative voltage V _b is applied between the thermal electron emission layer and the conductive substrate to obtain a photocurrent value I _b in the loop; and the photocurrent I _{a is} calculated I _b ratio of currents I _a / I _b; and the current ratio and the current ratio of different wavelengths of light under the same environment as the conventional control, to obtain the wavelength of monochromatic light to be calibrated.

In some embodiments of the present disclosure, the absolute values of the negative voltages V _a and V _b are between 1V and 100V, and the higher one is at least 1.5 times the other.

(3) Beneficial effects

The device, system and method for monochromatic optical wavelength identification of the present disclosure have at least one of the following beneficial effects:

(1) Based on the new principle of thermal electron energy distribution, an unprecedented monochromatic optical wavelength identification device structure is provided;

(2) The wavelength recognition is realized by the method of photocurrent ratio, and the wavelength recognition capability of the monochromatic light can be ensured at the same time;

(3) The device is a thermal electron emission layer-insulation layer-conducting substrate (EIC) structure, which breaks through the limitation of thermal electron scattering and is not affected by the scattering of hot electrons in the entire insulating layer, and is only determined by the thermal electron emission layer in the thermal electron emission layer. / The behavior at the interface of the insulating layer, therefore, the thickness of the insulating layer can be as high as several tens of nanometers, thereby avoiding leakage of the insulating layer and ensuring the reliability of the entire device.

DRAWINGS

1 is a schematic cross-sectional view of a monochromatic light wavelength identification device in accordance with an embodiment of the present disclosure.

2 is a flow chart of a method of monochromatic light wavelength identification in accordance with an embodiment of the present disclosure.

3 is a flow chart of a method of monochromatic light wavelength identification in accordance with an embodiment of the present disclosure.

Fig. 4 is a view showing the operation of the monochromatic light wavelength identifying device shown in Fig. 1.

Figure 5 is a graph showing the relationship between the current ratio of the monochromatic light wavelength identifying device shown in Figure 1 and the wavelength of a monochromatic light.

Figure 6 is a graph showing the relationship between the current ratio of the monochromatic light wavelength identifying device shown in Figure 1 and the monochromatic optical power.

Figure 7 is a graph showing photocurrent and dark current for the embodiment of the monochromatic light wavelength identification device of Figure 1.

FIG. 8 is a schematic structural view of a monochromatic light wavelength identification device according to a second embodiment of the present disclosure.

9 is a schematic structural view of a monochromatic light wavelength identification device according to a third embodiment of the present disclosure.

[Description of main component symbols in the embodiments of the present disclosure]

10-conductive substrate;

11-substrate; 12-conductive film layer;

20-insulation layer;

30-thermo electron emission layer;

41-first electrode; 42-second electrode.

detailed description

The present disclosure is based on a novel thermal electron energy distribution principle, and provides a monochromatic optical wavelength identification device having a thermal electron-emitting layer-insulation-electrical-conducting substrate (EIC) structure with an intermediate insulating layer thickness of several tens of nanometers, and provides A method of realizing monochromatic light wavelength recognition by reading a photocurrent ratio of a device.

The present disclosure will be further described in detail below with reference to the specific embodiments thereof and the accompanying drawings.

First, the first embodiment

In an exemplary embodiment of the present disclosure, a monochromatic light wavelength identification device is provided. 1 is a schematic cross-sectional view of a monochromatic light wavelength identification device in accordance with an embodiment of the present disclosure. As shown in FIG. 1, the monochromatic optical wavelength identification device of this embodiment includes:

Conductive substrate 10;

The insulating layer 20 is formed on the conductive substrate;

a thermal electron emission layer 30 formed of a metallic material on the insulating layer 20;

The first electrode 41 is formed on the conductive substrate 10 to form a good electrical connection therewith;

a second electrode 42 formed on the thermionic emission layer 30 to form a good electrical connection therewith;

Wherein, the conduction band of the insulating layer 20 has a higher Fermi level than the metallic material of the thermal electron emission layer, which corresponds to a barrier between the metallic material of the thermal electron emission layer and the conduction band of the insulating layer 20, through which The relationship between the barrier and the different thermal electron energy distributions excited by the monochromatic light in the thermal electron emission layer realizes the recognition of the wavelength of the monochromatic light.

The following is a detailed description of each component of the monochromatic optical wavelength identification device of the present embodiment. description.

In this embodiment, the conductive substrate 10 is a p-type doped Si substrate.

In other embodiments of the present disclosure, the conductive substrate may be a bulk substrate of a conductive material or a thin film of a conductive material formed on the non-conductive material. The conductive material may be a metal or a doped semiconductor material.

For metals, it should be satisfied that the work function of the metal is greater than or equal to the work function of the hot electron emission layer, which may be elemental metal, doped metal or alloy metal, such as gold (Au), silver (Ag), aluminum. (Al), copper (Cu), platinum (Pt), titanium (Ti), nickel (Ni), or the like.

For doped semiconductor materials, it should satisfy: resistivity <10 Ω·cm, and the work function of the semiconductor (ie, the difference between the semiconductor Fermi level and the vacuum level) is greater than the work function of the thermal electron emission layer. The semiconductor material may be a simple semiconductor or a compound semiconductor. For an elemental semiconductor, it may be Si, Ge or the like. The compound semiconductor may be a III-V compound semiconductor such as gallium arsenide or gallium nitride, or may be a novel semiconductor such as silicon carbide or titanium oxide. For doping, it may be an n-type doping or a p-type doping. For n-type doping, the doping impurities may be phosphorus or other impurities. For p-type doping, the doping impurities may be boron or other impurities.

In this embodiment, the insulating layer is a SiO ₂ film formed by a thermal oxidation process on a p-type doped Si substrate, and has a thickness of 40 nm.

In other embodiments of the present disclosure, the insulating layer may also be an insulating film formed of other inorganic or organic materials having insulating properties, and has a thickness of between 5 nm and 1000 nm. Inorganic material forming the insulating layer, for _{example: Al 2 O 3, SiN x} , Ta 2 O 5, HfO 2, Ga 2 O 3. The organic substance forming the insulating layer is, for example, polymethyl methacrylate (PMMA).

Since the monochromatic optical wavelength identification device of the present embodiment is in the form of a thermal electron emission layer-insulation layer-conductive substrate (EIC), the thermal electron scattering limitation is exceeded, and the influence of the scattering of hot electrons in the entire insulating layer is determined only by heat. The behavior of electrons at the interface of the thermal electron emission layer/insulation layer, therefore, the thickness of the insulation layer can be as high as several tens of nanometers, thereby avoiding leakage of the insulation layer and ensuring the reliability of the entire device.

In this embodiment, the thermal electron emission layer is an aluminum layer having a thickness of 15 nm.

In other embodiments of the present disclosure, the thermionic emission layer may also be a thin film formed of a metal or a metal compound, and may have a thickness of between 1 nm and 50 nm. The metal here is, for example, gold (Au), silver (Ag), aluminum (Al), copper (Cu), platinum (Pt), titanium (Ti), nickel (Ni) or the like. The metallic compound herein is, for example, ThO ₂ , La ₂ O ₃ , CeO ₂ , Y ₂ O ₃ , or LaB ₆ .

In the present embodiment, the insulating layer 20 and the thermionic emission layer 30 are formed in a partial region of the upper surface of the conductive substrate 10, and the insulating layer 20 and the thermionic emission layer 30 are not formed in the other portion. Regarding such a structure, it may be formed directly by occlusion or the like, or an insulating layer and a thermal electron emission layer may be formed on the entire upper surface of the conductive substrate, and then the insulating layer and the thermoelectron emission layer of the set region are micromachined. Remove formation.

The first electrode 41 is a positive electrode formed on a surface of the conductive substrate 10 where the insulating layer 20 and the thermionic emission layer 30 are not formed, and forms a good electrical contact with the conductive substrate 10, and the material is composed from bottom to top. Ti/Al/Ti/Au, the thickness is 20 nm / 30 nm / 20 nm / 300 nm, respectively. The second electrode 42 is a negative electrode formed on the thermionic emission layer 30 to form good electrical contact with the thermionic emission layer 30. The material is Ti/Al/Ti/Au from bottom to top and has a thickness of 20 nm. /30nm/20nm/300nm.

In other embodiments of the present disclosure, with respect to the first electrode 41 and the second electrode 42, one of them is a positive electrode, and the other is a negative electrode. The two are prepared by using a metal material such as Au or Pt or a non-metal material such as ITO, and may be a single layer electrode or a multilayer electrode as shown in this embodiment.

So far, the structure of the monochromatic optical wavelength identification device of the present embodiment has been described.

Second, the second embodiment

In a second exemplary embodiment of the present disclosure, a monochromatic optical wavelength identification system is also provided. 2 is a schematic structural view of a monochromatic light wavelength identification system according to a second embodiment of the present disclosure. As shown in FIG. 2, the monochromatic optical wavelength identification system of this embodiment includes: a measurement loop and a control processing module.

The measurement loop includes a monochromatic optical wavelength identification device, a bias supply device, and a photocurrent measurement device that are connected in series and form a loop. Among them, the monochromatic light wavelength identifying device is the monochromatic light wavelength identifying device of the first embodiment.

a control processing module for controlling the bias supply device to provide a bias voltage to the monochromatic optical wavelength identification device in the loop and recording the current in the loop, and for calculating the current values corresponding to the two different bias voltages (I _a and I _b The ratio (I _a /I _b ) is compared with the current ratio of different light wavelengths in the same environment to obtain the wavelength of the monochromatic light to be calibrated.

It will be apparent to those skilled in the art that in a monochromatic optical wavelength identification system, the function of the control processing module can also be implemented by an operator. In this case, the control processing module can be omitted.

So far, the introduction of the monochromatic light wavelength identification system of this embodiment has been completed.

Third, the third embodiment

The present disclosure also provides a method of monochromatic light wavelength recognition based on the monochrome light wavelength recognition system of the second embodiment. 3 is a flow chart of a method of monochromatic light wavelength identification in accordance with an embodiment of the present disclosure. As shown in FIG. 3, the method for identifying the wavelength of the monochromatic light includes:

Step A: placing the monochromatic light wavelength identification device in a monochromatic light irradiation environment, and receiving the monochromatic light irradiation to be calibrated by the thermal electron emission layer (Al layer);

Step B: applying a negative voltage V _a between the thermal electron emission layer (Al layer) and the conductive substrate (p-doped Si) to obtain a photocurrent value I _a in the loop; in the thermal electron emission layer (Al layer) Applying a negative voltage V _b to the conductive substrate (p-doped Si) to obtain a photocurrent value I _b in the loop;

In this embodiment, V _a and V _b are 2V and 4V. It should be noted that V _a and V _b can also select other values, such as 1V and 4V, 3V and 5V, and the like. Taking into account the accuracy and safety of the device, the voltage ranges of V _a and V _b are both 1 V to 100 V, and the higher one of V _a and V _b is at least 1.5 times the other.

Step C: calculated photocurrent I _a ratio of currents I _b and I _a / I _b;

Step D: The current ratio is compared with the current ratio of different light wavelengths in the same environment to obtain the wavelength of the monochromatic light to be calibrated.

Since monochromatic light of different wavelengths is irradiated to the thermal electron emission layer, different thermal electron energy distributions are generated, and different thermal electron energy distributions will cause different ratios of photocurrents at any two voltages. Therefore, the current ratio I _a /I _b has a one-to-one correspondence with the wavelength of the monochromatic light. When an unknown monochromatic light is irradiated to the sample, the monochromatic light wavelength can be judged by measuring the current ratio I _a /I _b .

的范围在E_f到

之间，其中E_f和

分别代表费米能级和入射光子能量。当负偏压施加在金属层时，能量高于金属/绝缘体界面势垒Φ_B(V)的热电子将发射到绝缘层的导带，形成光电流I_a，如图4中a所示。随着负偏压的降低，由于镜像力降低效应(image force lowing effect)，Φ_B(V)降低，降低速率正比于电压绝对值的平方根(Φ_B(V)＝Φ₀(V)-(q|V|/4π∈₀K_Hd)^1/2，其中K_H为高频介电常数，V和d分别为外加电压和绝缘层厚度)，使得更多的热电子能够发射到绝缘层的导带，形成更大的光 电流，I_b。对于不同的入射光波长，电流比率I_a/I_b是不同的，如图4中a，b，c。随着波长增加，

的上限向界面势移动，初始光电流I_a变小，I_a/I_b随着减小。这意味着长波长单色光将激发出更小的电流比率I_a/I_b。因此，通过测量器件的电流比率能够实现单色光波长的识别。Fig. 4 is a view showing the operation of the monochromatic light wavelength identifying device shown in Fig. 1. When light is irradiated onto the thermal electron emission layer, hot electrons are generated in the thermal electron emission layer. Thermal electron energy distribution

The range is in E _f to

Between, where E _f and

Represents the Fermi level and incident photon energy, respectively. When a negative bias is applied to the metal layer, hot electrons having an energy higher than the metal/insulator interface barrier Φ _B (V) will be emitted to the conduction band of the insulating layer to form a photocurrent I _a as shown in a of FIG. As the negative bias voltage decreases, Φ _B (V) decreases due to the image force lowing effect, and the rate of decrease is proportional to the square root of the absolute value of the voltage (Φ _B (V) = Φ ₀ (V) - ( q|V|/4π∈ ₀ K _H d) ^1/2 , where K _H is the high-frequency dielectric constant, V and d are the applied voltage and the thickness of the insulating layer, respectively, so that more hot electrons can be emitted to the insulating layer The conduction band forms a larger photocurrent, I _b . The current ratio I _a /I _b is different for different incident light wavelengths, as in a, b, c in FIG. As the wavelength increases,

The upper limit moves toward the interface potential, the initial photocurrent I _a becomes smaller, and I _a /I _b decreases. This means that long wavelength monochromatic light will excite a smaller current ratio I _a /I _b . Therefore, the identification of the wavelength of the monochromatic light can be achieved by measuring the current ratio of the device.

Figure 5 is a graph showing the relationship between the current ratio of the monochromatic light wavelength identifying device shown in Figure 1 and the wavelength of a monochromatic light. Referring to FIG. 5, V _a and V _{b are} selected to be 2V and 4V, and I _a and I _b correspond to photocurrents at 2V and 4V, respectively. It can be seen that the current ratio has a one-to-one correspondence with the wavelength of the monochromatic light. As the wavelength of the monochromatic light changes from 260 nm to 360 nm, the current ratio decreases monotonically from 0.49 to 0.06. Therefore, when monochromatic light of unknown wavelength is irradiated to the sample, by applying a voltage of 2V and 4V to the sample, the corresponding photocurrent ratio is calculated and compared with the curve shown in FIG. 5, and the corresponding monochromatic light can be obtained. wavelength.

Figure 6 is a graph showing the relationship between the current ratio of the monochromatic light wavelength identifying device shown in Figure 1 and the monochromatic optical power. As shown in FIG. 6, the monochromatic light wavelengths are 290 nm and 320 nm, respectively, and the optical power varies from 10 μW to 60 μW. It can be seen that when the optical power changes, the current ratio is maintained around a specific value corresponding to the wavelength. Therefore, the wavelength identification device of the present embodiment has power uncorrelated characteristics, and in practical applications, the wavelength of the monochromatic light can be resolved without considering the illumination light power value.

Fig. 7 is a graph showing photocurrent and dark current of the monochromatic light wavelength identifying device shown in Fig. 1. As shown in FIG. 7, the dark current of the photodetector device of the monochromatic light wavelength of the present embodiment is very low, less than 2×10 ^-13 A, and the photocurrent curve of the monochromatic light with a power of 100 uw and a wavelength of 290 nm is also shown in the figure. The signal to noise ratio is as high as 1×10 ⁴ . The extremely low dark current and high signal-to-noise ratio of the device ensure the reliability and usability of the device in practical applications.

Second, the second embodiment

In a second embodiment of the present disclosure, another monochromatic light wavelength identifying device is also provided. FIG. 8 is a schematic structural view of a monochromatic light wavelength identification device according to a second embodiment of the present disclosure. The monochromatic optical wavelength identifying device of the present embodiment is different from the monochromatic optical wavelength identifying device of the first embodiment in that the conductive substrate 10 includes a substrate body 11 and a conductive thin film layer 12 formed on the substrate 11. Wherein, the substrate 11 may be a conductive substrate, an insulating substrate or a semiconductor substrate. The material of the conductive thin film layer 12 can be selected from any one of the conductive substrates in the first embodiment.

The monochromatic optical wavelength identification device of this embodiment is other than the conductive substrate and based on The method for identifying the monochromatic light wavelength is similar to that of the first embodiment and will not be described in detail herein.

Third, the third embodiment

In a second embodiment of the present disclosure, another monochromatic light wavelength identifying device is also provided. 9 is a schematic structural view of a monochromatic light wavelength identification device according to a third embodiment of the present disclosure. The monochromatic optical wavelength identifying device of the present embodiment is different from the monochromatic optical wavelength identifying device of the first embodiment in that the first electrode 41 is formed on the back surface of the conductive substrate 10.

Since the conductive substrate 10 as a whole is electrically conductive, the first electrode 41 is formed on the back surface of the conductive substrate and can have the same effect as good electrical contact therewith. Also, the first electrode 41 is formed on the back surface of the conductive substrate, and the area of the thermionic emission layer can also be increased.

The monochromatic optical wavelength identification device of the present embodiment is similar to the first embodiment except for the conductive substrate and the monochrome light wavelength recognition method based thereon, and will not be described in detail herein.

Heretofore, the embodiments of the present disclosure have been described in detail in conjunction with the accompanying drawings. It should be noted that the implementations that are not shown or described in the drawings or the text of the specification are all known to those of ordinary skill in the art and are not described in detail. In addition, the above definitions of the various elements and methods are not limited to the specific structures, shapes or manners mentioned in the embodiments, and those skilled in the art can simply modify or replace them.

Based on the above description, those skilled in the art should have a clear understanding of the devices and methods for identifying the wavelength of monochromatic light of the present disclosure.

In summary, the present disclosure provides a monochromatic optical wavelength identification of a thermal electron-emitting layer-insulation-electrical-conducting (EIC) structure having an intermediate insulating layer thickness of up to several tens of nanometers based on a novel thermal electron energy distribution principle. A device and a method for achieving monochromatic wavelength recognition by reading the photocurrent ratio of the device.

It should also be noted that the directional terms mentioned in the embodiments, such as "upper", "lower", "front", "back", "left", "right", etc., are only referring to the directions of the drawings, not It is intended to limit the scope of protection of the present disclosure. Throughout the drawings, the same elements are denoted by the same or similar reference numerals. Conventional structures or configurations will be omitted when it may cause confusion to the understanding of the present disclosure.

Further, the shapes and sizes of the components in the drawings do not reflect the true size and proportion, but merely illustrate the contents of the embodiments of the present disclosure. In addition, any reference signs placed between parentheses should not be construed as a limitation.

Unless otherwise stated to the contrary, the numerical parameters in this specification and the appended claims are Approximate values can vary depending on the desired characteristics obtained through the teachings of the present disclosure. In particular, all numbers expressing the content, reaction conditions, and the like, which are used in the specification and claims, are to be understood as being modified by the term "about" in all cases. In general, the meaning of its expression is meant to encompass a variation of ±10% by a particular amount in some embodiments, a variation of ±5% in some embodiments, a variation of ±1% in some embodiments, in some implementations In the case of ±0.5% change.

Further, the word "comprising" does not exclude the presence of the elements or the steps that are not recited in the claims. The word "a" or "an"

The use of ordinal numbers such as "first," "second," "third," and the like, as used in the <Desc/Clms Page number>> It does not represent the order of one element and another element, or the order of the method of manufacture. The use of these ordinal numbers is only used to enable a component having a certain name to be clearly distinguished from another element having the same name.

In addition, the order of the above steps is not limited to the above, and may be varied or rearranged depending on the desired design, unless specifically described or necessarily occurring in sequence. The above embodiments may be used in combination with other embodiments or based on design and reliability considerations, that is, the technical features in different embodiments may be freely combined to form more embodiments.

In the description of the exemplary embodiments of the present disclosure, the various features of the present disclosure are sometimes grouped together into a single embodiment, Figure, or a description of it. However, the method disclosed is not to be interpreted as reflecting the intention that the claimed invention requires more features than those recited in the claims. Rather, as disclosed in the following claims, the disclosed aspects are less than all features of the single embodiments disclosed herein. Therefore, the claims following the specific embodiments are hereby explicitly incorporated into the specific embodiments, and each of the claims as a separate embodiment of the present disclosure.

The specific embodiments of the present invention have been described in detail with reference to the specific embodiments of the present disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and scope of the present disclosure are intended to be included within the scope of the present disclosure.

Claims (15)

A monochromatic optical wavelength identification device comprising: Conductive substrate; An insulating layer formed on the conductive substrate; a thermal electron emission layer formed of a metallic material on the insulating layer; Wherein, the conduction band of the insulating layer is higher than the Fermi level of the metallic material of the thermal electron emission layer. The monochromatic light wavelength identifying device according to claim 1, wherein said thermoelectron emitting layer is a film having a thickness of from 1 nm to 50 nm formed of a metal thin film or a compound having a metallic property. A monochromatic light wavelength identifying device according to claim 2, wherein: The metal is a composite material of one or more of the following materials: gold, silver, aluminum, copper, platinum, titanium, nickel; The metal compound is one of the following materials: ThO ₂ , La ₂ O ₃ , CeO ₂ , Y ₂ O ₃ , LaB ₆ . The monochromatic light wavelength identifying device according to claim 1, wherein said insulating layer is an inorganic insulating film or an organic insulating film having a thickness of between 5 nm and 1000 nm. The monochromatic light wavelength identifying device according to claim 4, wherein The material forming the organic insulating film is PMMA; The material forming the inorganic insulating film is one or more of the following materials: Al ₂ O ₃ , SiN _x , Ta ₂ O ₅ , HfO ₂ , Ga ₂ O ₃ . A monochromatic light wavelength identifying device according to claim 1, said conductive substrate, a body substrate that is a conductive material; or The method includes a substrate body and a thin film of a conductive material formed on the substrate body. A monochromatic light wavelength identification device according to claim 6, wherein said conductive material is: a metal whose work function is greater than or equal to the work function of the thermionic emission layer; or A doped semiconductor material having a resistivity of <10 Ω·cm and a work function greater than that of the thermal electron emission layer. The monochromatic light wavelength identifying device according to claim 1, wherein The conductive substrate is a p-type doped Si substrate; The insulating layer is a SiO ₂ film formed on the p-type doped Si substrate; The thermionic emission layer is an aluminum layer formed on the SiO ₂ film. The monochromatic light wavelength identification device according to any one of claims 1 to 8, further comprising: a first electrode electrically connected to the conductive substrate; The second electrode is electrically connected to the thermal electron emission layer. A monochromatic light wavelength identifying device according to claim 9, wherein: The conductive substrate is a bulk substrate of a conductive material, and the first electrode and the insulating layer are formed on the same surface or different surfaces of the conductive substrate; or The conductive substrate comprises: a substrate body and a film of a conductive material formed on the substrate body, wherein the first electrode and the insulating layer are both formed on the film of the conductive material. A monochromatic optical wavelength identification system comprising: a measurement loop; The measurement circuit includes a monochromatic optical wavelength identification device, a bias supply device, and a photocurrent measurement device that are connected in series and form a loop, and the monochromatic optical wavelength identification device is the monochromatic optical wavelength identification device according to claim 9. The monochromatic light wavelength identification system of claim 11 further comprising: Control processing module for: Controlling the bias supply means to provide a bias to the monochromatic optical wavelength identifying device and to record the current in the loop measured by the photocurrent measuring device; Calculate the current ratio of the current values corresponding to the two different bias voltages, and compare the current ratio with the ratio of the different optical wavelengths in the same environment to obtain the wavelength of the monochromatic light to be calibrated. A monochromatic optical wavelength identification system according to claim 13 wherein said control processing module stores a relationship between the wavelength of the monochromatic light and the corresponding current ratio. A monochromatic light wavelength identification method based on the monochromatic light wavelength identification device according to any one of claims 1 to 8, comprising: Receiving a monochromatic light irradiation to be calibrated by a thermal electron emission layer of a monochromatic light wavelength identification device; Applying a negative voltage V _a between the thermal electron emission layer and the conductive substrate to obtain a photocurrent value I _a in the loop; applying a negative voltage V _b between the thermal electron emission layer and the conductive substrate to obtain a photocurrent value I in the loop _b ; Calculate a light current I _a and I _b ratio of currents I _a / I _b; and The current ratio is compared with the current ratio of different light wavelengths in the same environment to obtain the wavelength of the monochromatic light to be calibrated. Monochromatic wavelength identification method according to claim 14, the absolute value of the negative voltage V _a and V _b is between 1V ~ 100V, a higher is at least 1.5 times the other.

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