Niobium telluride terahertz photoelectric detector based on logarithmic composite antenna integration and manufacturing method thereof

Abstract

The invention relates to a niobium telluride terahertz photoelectric detector based on logarithmic composite antenna integration and a preparation method thereof, which are characterized in that a niobium telluride material obtained by mechanical stripping is transferred to an intrinsic high-resistance silicon substrate through a dry method, and a source electrode, a drain electrode and a corresponding antenna structure are manufactured by using an ultraviolet lithography technology. And the logarithmic composite antenna niobium telluride terahertz photoelectric detector is prepared by using processes such as electron beam evaporation and the like. Compared with a traditional logarithmic antenna, the logarithmic composite antenna structure has higher field intensity gain on terahertz waves, so that the logarithmic composite antenna niobium telluride terahertz photoelectric detector has higher sensitivity on the terahertz waves.

Description

Technical Field

[0001] The present invention relates to the technical field of terahertz detection devices, and in particular to a niobium telluride terahertz photoelectric detector based on logarithmic composite antenna integration and a manufacturing method thereof. Background Art

[0002] The frequency range of terahertz is 0.1THz-10THz, and it has unique physical properties, such as high penetration, low photon energy, high frequency, and wide bandwidth. The terahertz band has great application value, such as non-destructive testing, safety inspection, medical imaging, 6G mobile communications, terahertz radar, etc. However, since the terahertz band is between microwave electronics and infrared photonics, it is difficult to use traditional microwave detection technology or infrared photon detection technology to detect the terahertz band. Although the existing pyroelectric terahertz detector can achieve high sensitivity, the response time is very long, about milliseconds; thermal radiation meters can achieve high sensitivity, but they need to work in low temperature environments, which increases costs. Therefore, it is necessary to develop a terahertz detector that responds to the terahertz band at room temperature and has a short response time.

[0003] At the same time, the existing terahertz wave detection requires the optimization design of the terahertz antenna so that the terahertz antenna can achieve a higher gain effect. Otherwise, the amplification of the terahertz signal will increase the detection cost of the terahertz signal. In addition, in order to adapt to the low-temperature working environment, an additional refrigeration device is required, resulting in a larger device size. The existing traditional terahertz antenna structure can effectively amplify the gain of the terahertz wave field, but the terahertz antenna needs to be further optimized to achieve more sensitive detection of the terahertz wave, thereby reducing the power of the terahertz source and reducing the cost of terahertz wave detection. Summary of the invention

[0004] The purpose of the present invention is to provide a niobium telluride terahertz photoelectric detector based on logarithmic composite antenna integration and a manufacturing method thereof, which solves the problem that although the existing pyroelectric terahertz detector can achieve very high sensitivity, the response time is very long, about the order of milliseconds; the thermal radiation meter can achieve very high sensitivity, but needs to work under low temperature environmental conditions, which increases the cost and the bulkiness of the equipment.

[0005] To achieve the above object, the technical solution of the present invention is:

[0006] A niobium telluride terahertz photodetector based on logarithmic composite antenna integration includes a high-resistance silicon substrate and a channel material layer arranged on the high-resistance silicon substrate; the characteristics are: the channel material layer is made of niobium telluride; a source electrode and a drain electrode are respectively arranged at both ends of the channel material layer;

[0007] The source electrode includes a source electrode plate, a source electrode lead, a source electrode logarithmic antenna and a source electrode antenna connected in sequence from the outside to the inside; the drain electrode includes a drain electrode plate, a drain electrode lead, a drain electrode logarithmic antenna and a drain electrode antenna connected in sequence from the outside to the inside;

[0008] The source electrode antenna and the drain electrode antenna form a channel at the center of the channel material layer;

[0009] The source electrode antenna is a 90-degree spiral antenna, and the drain electrode antenna is also a 90-degree spiral antenna matched with the source electrode antenna. The source electrode antenna and the drain electrode antenna form an S-shaped symmetrical channel in the channel material layer.

[0010] In niobium telluride materials, the atomic ratio of tellurium and niobium is 4:1.

[0011] The source electrode is made of chromium-gold composite metal, wherein the chromium metal layer is in contact with the channel material layer; the drain electrode is also made of chromium-gold composite metal, wherein the chromium metal layer is in contact with the channel material layer.

[0012] As described above, in the method for manufacturing a niobium telluride terahertz photodetector based on logarithmic composite antenna integration, step 1 is to perform Raman spectrum scanning on the niobium telluride material to select the niobium telluride material that produces periodic lattice distortion;

[0013] Step 2: Thinning the niobium telluride material by mechanical stripping to form a thinner niobium telluride two-dimensional material, and transferring the niobium telluride two-dimensional material to a high-resistance silicon substrate by dry transfer;

[0014] Step 3, using an ultraviolet photolithography process for exposure, and then using a developing process to make the photoresist show the source electrode structure and the drain electrode structure containing the logarithmic composite antenna;

[0015] Step 4: using an electron beam evaporation process to deposit chromium and gold materials on the channel material, and then using a lift-off process to form a source electrode and a drain electrode comprising a logarithmic composite antenna, wherein the source electrode antenna and the drain electrode antenna are arranged to be intertwined with each other, and the source electrode antenna is a 90-degree spiral antenna, and an S-shaped channel of niobium telluride material is formed at the center of the channel material layer;

[0016] Step five, stick the product of step four to the PCB board, and connect the source electrode plate and the drain electrode plate to the lead electrodes on the PCB board through a bonding process to prepare a niobium telluride terahertz photodetector based on logarithmic composite antenna integration.

[0017] The advantages of the present invention are: 1. Compared with the traditional logarithmic antenna, the logarithmic composite antenna structure can achieve higher gain for the field intensity of the terahertz wave, thereby enhancing the photoelectric response and sensitivity of the niobium telluride material to the terahertz wave; 2. The niobium telluride material belongs to the IC-CDW phase and has periodic lattice distortion, which can realize zero-bias photocurrent for the terahertz wave at room temperature, and can generate photocurrent for the terahertz wave without external power supply, thereby reducing the detection cost of the terahertz wave; 3. By using the CDW in the niobium telluride material to detect the terahertz wave, the response time can be increased from milliseconds to microseconds, and the room temperature detection effect of the terahertz wave can be achieved with high speed and high sensitivity; 4. Since the niobium telluride material is a two-dimensional van der Waals material, it is easy to realize large-area integration by CMOS process in the future, and it can be applied to electronic devices such as wearable devices, flexible displays, sensors, etc., which can make the electronic devices thinner and more flexible. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the logarithmic antenna structure of the prior art;

[0019] Figure 2 It is a schematic diagram of the logarithmic composite antenna structure in the present invention;

[0020] Figure 3 This is a Raman spectrum of the niobium telluride material of the present invention. The abscissa of the figure represents the Raman shift in cm. -1 , the ordinate is the normalized intensity;

[0021] Figure 4 1 is a gain diagram of the logarithmic antenna structure of the prior art and the logarithmic composite antenna structure of the present invention to the terahertz electric field, the abscissa is the terahertz frequency in GHz, and the ordinate is the field intensity gain of the antenna structure to the terahertz wave;

[0022] Figure 5 The photoelectric response spectra of the niobium telluride terahertz photodetector with the logarithmic antenna of the prior art and the logarithmic composite antenna structure of the present invention to different frequencies, the abscissa is the frequency of the terahertz wave, in GHz, and the ordinate is the photocurrent generated by the terahertz detector to the terahertz wave, in μA;

[0023] Figure 6 This is a response time diagram of the niobium telluride terahertz photodetector based on logarithmic composite antenna integration to terahertz waves of the present invention, the abscissa is time in μs, and the ordinate is normalized photocurrent.

[0024] In the figure: 1-source electrode plate; 2-source electrode lead; 3-source electrode logarithmic antenna; 4-drain electrode logarithmic antenna; 5-drain electrode lead; 6-drain electrode plate; 7-source electrode antenna; 8-drain electrode antenna; 9-channel material layer. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with the accompanying drawings, which are only used for exemplary description and cannot be understood as limiting the present invention.

[0026] In order to more concisely describe the present embodiment, some parts known to those skilled in the art but not related to the main content of the present invention are omitted in the drawings or descriptions. In addition, for the convenience of description, some parts in the drawings are omitted, enlarged or reduced, but they do not represent the size or entire structure of the actual product.

[0027] The present invention discloses a niobium telluride terahertz photodetector based on logarithmic composite antenna integration, comprising a high-resistance silicon substrate and a channel material layer 9 arranged on the high-resistance silicon substrate; the channel material layer 9 is made of niobium telluride, and preferably, in the niobium telluride material, the atomic ratio of tellurium to niobium is 4:1.

[0028] like Figure 2 As shown, a source electrode and a drain electrode are respectively arranged at both ends of the channel material layer 9; the source electrode includes a source electrode plate 1, a source electrode lead 2, a source electrode logarithmic antenna 3 and a source electrode antenna 7 connected in sequence from the outside to the inside; the drain electrode includes a drain electrode plate 6, a drain electrode lead 5, a drain electrode logarithmic antenna 4 and a drain electrode antenna 8 connected in sequence from the outside to the inside.

[0029] The source electrode antenna 7 and the drain electrode antenna 8 form a channel at the center of the channel material layer 9; Figure 1 The difference between the prior art logarithmic antenna shown in FIG. 1 and FIG. 2 is that the prior art logarithmic antenna only has equally spaced channels, while the Figure 2 In the logarithmic composite antenna of the present invention shown, the source electrode antenna 7 and the drain electrode antenna 8 are 90-degree spiral antennas, and the source electrode antenna 7 and the drain electrode antenna 8 are intertwined with each other to form an S-shaped symmetrical channel on the channel material layer 9.

[0030] The source electrode is made of a chromium-gold composite metal, with an upper layer of gold and a lower layer of chromium, wherein the chromium metal layer is in contact with the channel material layer 9, and the upper layer of gold is connected to the external lead electrode; the drain electrode is also made of a chromium-gold composite metal, with an upper layer of gold and a lower layer of chromium, wherein the chromium metal layer is in contact with the channel material layer 9, and the upper layer of gold is connected to the external lead electrode.

[0031] The manufacturing method of the above-mentioned niobium telluride terahertz photodetector based on logarithmic composite antenna integration,

[0032] Step 1: Scan the niobium telluride material with a Raman spectrum to determine whether the niobium telluride material has undergone a charge density wave phase transition at room temperature, the number of Raman modes in a distorted state, and select the niobium telluride material that produces periodic lattice distortion;

[0033] like Figure 3As shown in Figure 1, in addition to the Raman modes that the niobium telluride material itself should have, the Raman spectrum of the niobium telluride material also has a Raman mode caused by periodic lattice distortion: E 1u , B 1u , so we conclude that the material produces periodic lattice distortion at room temperature due to the charge density wave effect.

[0034] Step 2: Thinning the niobium telluride material by mechanical stripping to form a thinner niobium telluride two-dimensional material, and transferring the niobium telluride two-dimensional material to a high-resistance silicon substrate by dry transfer;

[0035] Step 3, using an ultraviolet photolithography process for exposure, and then using a developing process to make the photoresist show the source electrode structure and the drain electrode structure containing the logarithmic composite antenna;

[0036] Step 4: using an electron beam evaporation process to deposit chromium and gold materials on the channel material, and then using a lift-off process to form a source electrode and a drain electrode comprising a logarithmic composite antenna, wherein the source electrode antenna 7 and the drain electrode antenna 8 are configured as mutually intertwined 90-degree spiral antennas, and an S-shaped channel of niobium telluride material is formed at the center of the channel material layer 9;

[0037] Step five, stick the product of step four to the PCB board, and connect the source electrode plate 1 and the drain electrode plate 6 to the lead electrodes on the PCB board through a bonding process to prepare a niobium telluride terahertz photodetector based on logarithmic composite antenna integration.

[0038] The microwave source is used to add triple frequency and nine frequency modules to output terahertz waves, and the preamplifier is used to amplify the signal, and the lock-in amplifier is used to extract the terahertz signal detected by the terahertz detector. The ambient temperature of all measurements is room temperature, and the test conditions are all under zero bias voltage.

[0039] Figure 4 The figure shows the gain diagram of the logarithmic antenna of the prior art and the logarithmic composite antenna structure of the present invention to the terahertz electric field. By comparing the gain of the logarithmic antenna of the prior art and the logarithmic composite antenna structure of the present invention to the terahertz electric field, it can be known that the gain of the logarithmic composite antenna structure of the present invention to the terahertz wave field intensity is about 3 times that of the logarithmic antenna structure of the prior art.

[0040] Figure 5 The photoelectric response spectra of the terahertz photodetector with the logarithmic antenna of the prior art and the niobium telluride terahertz photodetector based on the logarithmic composite antenna of the present invention to different frequencies are shown. By comparing the photoelectric responses of the prior art and the present invention, it can be seen that the niobium telluride terahertz detector based on the logarithmic composite antenna structure of the present invention can generate a stronger photocurrent signal for terahertz, thereby confirming the advantages of the present invention over the terahertz detector of the prior art.

[0041] Figure 6 This is a graph of the response time of the niobium telluride terahertz photodetector based on the logarithmic composite antenna structure to terahertz waves. According to the definition of response time, the rise time is the time taken for the signal to rise from 10% to 90% of the maximum signal, and the fall time is the time taken for the signal to fall from 90% to 10% of the maximum signal. It can be seen that the rise time and fall time of the present invention are 2.2μs and 2.3μs respectively, both of which are in the microsecond level. This response time is much better than the millisecond response time of the terahertz pyroelectric detector at room temperature.

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. That is, any equivalent changes and modifications made according to the content of the patent application scope of the present invention should be within the technical scope of the present invention.

Claims

1. A niobium telluride terahertz photodetector based on logarithmic composite antenna integration, comprising a high-resistance silicon substrate and a channel material layer (9) arranged on the high-resistance silicon substrate; characterized in that: The channel material layer (9) is made of niobium telluride; a source electrode and a drain electrode are respectively arranged at two ends of the channel material layer (9); The source electrode comprises a source electrode plate (1), a source electrode lead (2), a source electrode logarithmic antenna (3) and a source electrode antenna (7) which are connected in sequence from the outside to the inside; the drain electrode comprises a drain electrode plate (6), a drain electrode lead (5), a drain electrode logarithmic antenna (4) and a drain electrode antenna (8) which are connected in sequence from the outside to the inside; The source electrode antenna (7) and the drain electrode antenna (8) form a channel at the center of the channel material layer (9); The source electrode antenna (7) is a 90-degree spiral antenna, and the drain electrode antenna (8) is also a 90-degree spiral antenna adapted to the source electrode antenna (7). The source electrode antenna (7) and the drain electrode antenna (8) form an S-shaped symmetrical channel in the channel material layer (9).

2. The niobium telluride terahertz photodetector based on logarithmic composite antenna integration according to claim 1, characterized in that: In niobium telluride materials, the atomic ratio of tellurium and niobium is 4:

1.

3. The niobium telluride terahertz photodetector based on logarithmic composite antenna integration according to claim 2, characterized in that: The source electrode is made of a chromium-gold composite metal, wherein the chromium metal layer is in contact with the channel material layer (9); the drain electrode is also made of a chromium-gold composite metal, wherein the chromium metal layer is in contact with the channel material layer (9).

4. The method for manufacturing a niobium telluride terahertz photodetector based on logarithmic composite antenna integration according to claim 3, characterized in that: Step 1: Scan the niobium telluride material with Raman spectroscopy to select the niobium telluride material that produces periodic lattice distortion; Step 2: Thinning the niobium telluride material by mechanical stripping to form a thinner niobium telluride two-dimensional material, and transferring the niobium telluride two-dimensional material to a high-resistance silicon substrate by dry transfer; Step 3, using an ultraviolet photolithography process for exposure, and then using a developing process to make the photoresist show the source electrode structure and the drain electrode structure containing the logarithmic composite antenna; Step 4: using an electron beam evaporation process to deposit chromium and gold materials on the channel material, and then using a lift-off process to form a source electrode and a drain electrode comprising a logarithmic composite antenna, wherein the source electrode antenna (7) and the drain electrode antenna (8) are arranged as mutually intertwined 90-degree spiral antennas, and an S-shaped channel of niobium telluride material is formed at the center of the channel material layer (9); Step 5, bonding the product of step 4 to a PCB board, and connecting the source electrode plate (1) and the drain electrode plate (6) to the lead electrodes on the PCB board through a bonding process to prepare a niobium telluride terahertz photodetector based on logarithmic composite antenna integration.

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