Thermoelectric integrated transmission electron microscope in-situ high-frequency test chip

Abstract

The invention relates to a thermoelectric integrated transmission electron microscope in-situ high-frequency test chip, and the chip comprises a silicon substrate which is provided with an insulating layer on the surface; the silicon nitride film is arranged at the position of the observation window on the silicon substrate; the high-frequency circuit is positioned on the insulating layer on the front surface of the silicon substrate and comprises a first input electrode and a first grounding electrode, and the first input electrode is connected through an inverted U-shaped sample parallel resistor in a region close to the sample; and the heating circuit is positioned on the insulating layer on the surface of one side of the silicon substrate, forms a zigzag resistor structure, and comprises at least one second input electrode and a second grounding electrode. Compared with the prior art, heating and high-frequency electrical measurement are integrated on the same chip, so that synchronous temperature regulation and control and high-frequency signal test of a sample at 23-700 DEG C and 0-3GHz can be realized.

Description

Technical Field

[0001] The invention belongs to the technical field of electron microscope testing, and relates to a thermoelectric integrated transmission electron microscope in-situ high-frequency testing chip. Background Art

[0002] In-situ transmission electron microscopy (TEM) testing is an important tool for studying the physical properties of nanomaterials, electronic devices, and interfaces. This technology enables real-time observation of the structural evolution of materials at the atomic scale and, combined with external field manipulations such as electrical and thermal fields, enables multi-dimensional in-situ measurements. Among the many in-situ TEM techniques, in-situ electrical test chips, serving as a crucial interface between external electronic devices and samples, are widely used in areas such as studying the transport properties of low-dimensional materials and analyzing the reliability of nanodevices.

[0003] In-situ heating test chips have been widely used to study the evolution of materials under different temperature conditions. These chips typically utilize microfabrication techniques to integrate heating electrodes on silicon or ceramic substrates. This provides precise temperature control, enabling researchers to probe material stability, phase transition behavior, and temperature-dependent electrical properties in high-temperature environments. However, existing heating chips are primarily designed for static or low-frequency electrical measurements, making them difficult to meet the research needs of high-frequency electronic devices and radio frequency materials.

[0004] On the other hand, high-frequency electrical testing is also crucial in the fields of nanoelectronics, quantum devices, and radio frequency materials. Patent CN109270099B proposes an in-situ high-frequency test chip suitable for transmission electron microscopy, which realizes high-frequency signal measurement in the frequency range of 0 to 6 GHz. This type of chip can detect the electrical characteristics of nanosecond pulse signals and microwave frequencies, providing an important means for the research of radio frequency electronic devices and high-frequency materials. However, since it does not have a temperature control function, it is difficult to characterize the high-frequency electrical characteristics of materials under different temperature conditions in practical applications, which limits the research on temperature-dependent electronic processes. Summary of the Invention

[0005] The purpose of the present invention is to provide a thermoelectric integrated transmission electron microscope in-situ high-frequency test chip, which integrates heating and high-frequency electrical measurement on the same chip, and can achieve synchronous temperature control and high-frequency signal testing of samples at 23-700°C and 0-3GHz.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A thermoelectric integrated transmission electron microscope in-situ high-frequency test chip, comprising:

[0008] A silicon substrate having an insulating layer on its surface;

[0009] A silicon nitride film is provided at the observation window position on the silicon substrate, and the silicon nitride film is located above the observation window and is used to support the heating circuit;

[0010] A high-frequency circuit located on the insulating layer on the front side of the silicon substrate comprises a first input electrode and a first grounding electrode, wherein the first input electrode is connected to the sample region through an inverted U-shaped sample parallel resistor;

[0011] And a heating circuit is located on the insulating layer on one side surface of the silicon substrate, which forms a meandering resistance structure and includes at least one second input electrode and a second grounding electrode.

[0012] Furthermore, the first input electrode and the second input electrode each have a measuring electrode near the sample end for in-situ signal measurement.

[0013] Furthermore, the resistance of the measuring electrode is 50-75Ω.

[0014] Furthermore, the first input electrode, the first ground electrode, the second input electrode, and the second ground electrode are symmetrically designed or asymmetrically designed.

[0015] Furthermore, the thickness of the silicon substrate is 100-300 μm, the thickness of the silicon nitride film is 15-80 nm, and the thickness of the heating circuit and the high-frequency circuit is 20-500 nm.

[0016] Furthermore, the inverted U-shaped sample parallel resistor is composed of a slender metal wire, and its resistance is 50-75Ω.

[0017] Furthermore, the thickness of the insulating layer on the front side of the silicon substrate is 1.5 to 5.0 μm.

[0018] Furthermore, the heating circuit is composed of Pt; and the high-frequency circuit is composed of Au.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] (1) Heating and high-frequency integrated design: The in-situ test chip of the present invention can be stably heated in the temperature range of 23 to 700°C and realize high-frequency signal transmission in the frequency range of 0 to 3 GHz, which improves the measurement integration compared with traditional solutions.

[0021] (2) Independent electrode port: The heating circuit and the high-frequency circuit are connected through an independent electrode port to reduce the mutual interference between the electrical signal and the thermal signal and improve the measurement accuracy.

[0022] (3) Wide applicability: It can be used to study the transport characteristics of two-dimensional materials, analyze the high-temperature stability of semiconductor devices, study the temperature gradient effect of thermoelectric materials, and simulate the high-frequency working state of radio frequency electronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the front structure of the transmission electron microscope in-situ high-frequency test chip of the present invention;

[0024] Figure 2 This is a schematic diagram of the front structure of the transmission electron microscope in-situ high-frequency test chip in the sample holder of the present invention;

[0025] Figure 3 、 4 The transmission electron microscope in-situ high-frequency test chip performance of the present invention;

[0026] Figure 5 This is a schematic diagram of the front structure of another embodiment of the transmission electron microscope in-situ high-frequency test chip of the present invention;

[0027] Description of the marks in the figure:

[0028] 1-Silicon substrate, 2-Silicon nitride film, 3-Heating circuit, 4-High-frequency circuit, 5-Sample parallel resistor, 6-First input electrode, 7-Left high-frequency circuit measurement electrode, 8-Second input electrode, 9-Left heating circuit measurement electrode, 10-Right heating circuit measurement electrode, 11-Second ground electrode, 12-Right high-frequency circuit measurement electrode, 13-First ground electrode. DETAILED DESCRIPTION

[0029] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0030] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0032] In the following implementation manners or examples, unless otherwise specified, functional components or structures are conventional components or conventional structures used in the art to achieve corresponding functions.

[0033] In order to achieve synchronous temperature control and high-frequency signal testing of samples at 23-700℃ and 0-3GHz, the present invention provides a thermoelectric integrated transmission electron microscope in-situ high-frequency test chip, see Figure 1 Shown, including:

[0034] A silicon substrate 1 having an insulating layer on its surface;

[0035] A silicon nitride film 2 is provided at an observation window position on a silicon substrate 1;

[0036] A high-frequency circuit 4 located on the insulating layer on the front side of the silicon substrate 1 includes a first input electrode and a first grounding electrode. The first input electrode is connected to the sample area through an inverted U-shaped sample parallel resistor 5;

[0037] And a heating circuit 3 located on the insulating layer on one side surface of the silicon substrate 1 forms a meandering resistance structure and includes at least one second input electrode and a second grounding electrode.

[0038] In the present invention, since the heating circuit and high-frequency circuit have independent electrode ports, the electrodes can be flexibly selected. Symmetrical or asymmetric designs can be adopted to optimize the electrical signal transmission path or thermal field distribution. Measuring electrodes can also be added to each input electrode or ground electrode to achieve real-time in-situ monitoring.

[0039] In some specific embodiments, the first input electrode and the second input electrode each further extend a measurement electrode near the sample end for in-situ signal measurement.

[0040] In a more specific embodiment, the resistance value of the measuring electrode is 50-75Ω, which can reduce the impact of the measuring circuit on the signal, and the measurement result needs to be corrected according to the chip resistance parameter.

[0041] In some specific embodiments, two of each of the first input electrode, the first ground electrode, the second input electrode, and the second ground electrode are provided.

[0042] In a more specific embodiment, the first input electrode, the first ground electrode, the second input electrode, and the second ground electrode are symmetrically designed or asymmetrically designed.

[0043] In some specific embodiments, the thickness of the silicon substrate 1 is 100 to 300 μm, the thickness of the silicon nitride film 2 is 15 to 80 nm, and the thickness of the heating circuit 3 and the high-frequency circuit 4 is 20 to 500 nm, so as to ensure that the chip is suitable for the test environment of the transmission electron microscope and to ensure the stable transmission of the high-frequency signal.

[0044] In some specific embodiments, the inverted U-shaped sample parallel resistor 5 is composed of a slender metal wire, and different metal materials (such as gold, chromium, and tantalum) are used to achieve the desired resistance by adjusting the wire length, and the final resistance value is controlled to be 50 to 75Ω to achieve impedance matching with the high-frequency signal input end.

[0045] In some specific embodiments, the thickness of the insulating layer on the front side of the silicon substrate 1 is 1.5-5.0 μm.

[0046] In some specific embodiments, the heating circuit 3 is composed of Pt to meet the requirements of high resistivity, small thermal expansion coefficient and Poisson's ratio of the heating circuit material; the high-frequency circuit 4 is composed of Au to meet the low resistivity requirement of the high-frequency circuit.

[0047] In summary, this invention integrates heating and high-frequency signal transmission functions on a single chip. By optimizing the electrode structure and impedance matching design, the chip can maintain stable high-frequency signal transmission in high-temperature environments, enabling electrical measurements with nanosecond time resolution. This technology can be widely applied to the study of the electrothermal coupling characteristics of two-dimensional materials, semiconductor devices, thermoelectric materials, and radio-frequency electronic devices.

[0048] The above embodiments may be implemented individually or in any combination of two or more.

[0049] The above implementation is described in more detail below with reference to specific examples.

[0050] Example 1

[0051] like Figure 1As shown, this embodiment provides an in-situ high-frequency electrical test chip suitable for transmission electron microscopy, including a silicon substrate 1 (with an insulating layer on its surface), a silicon nitride film 2, a heating circuit 3, a high-frequency circuit 4, a sample parallel resistor 5, a first input electrode 6, a left high-frequency circuit measurement electrode 7, a second input electrode 8, a left heating circuit measurement electrode 9, a right heating circuit measurement electrode 10, a second ground electrode 11, a right high-frequency circuit measurement electrode 12, and a first ground electrode 13. The thickness of the silicon substrate 1 is 100-300 μm, the thickness of the heating circuit 3 and the high-frequency circuit 4 is 20-500 nm, the insulating layer is made of SiN or SiC material, and the total thickness of the front insulating layer is 1.5-5.0 μm.

[0052] In this embodiment, in order to achieve in-situ precise measurement of the temperature of the sample area, a four-electrode temperature measurement method is adopted. Specifically, a current source electrode and a voltage measuring electrode are respectively provided at both ends of the heating circuit 3, wherein the second input electrode 8 and the second ground electrode 11 serve as current source electrodes for the heating circuit, and the left heating circuit measuring electrode 9 and the right heating circuit measuring electrode 10 serve as voltage measuring electrodes for voltage measurement. By applying a stable current to the heating circuit 3 and measuring the voltage across it in real time, the resistance value of the heating circuit 3 is calculated according to Ohm's law. Combined with the resistance-temperature characteristic curve of the heating material, the actual temperature at the sample can be inferred. This temperature measurement method can effectively avoid the error caused by contact resistance.

[0053] This chip features an optimized design based on a high-frequency test chip, combining a high-frequency circuit layout with a heating function. The sample's parallel resistor 5 is used for impedance matching at the microwave signal input, while independent electrodes, from the first input electrode 6 to the first ground electrode 13, are used for external connections. In actual testing, applying a 1V input voltage to the heating circuit stabilized the temperature at the center of the chip's sample region at approximately 752°C, with a temperature difference of no more than 40°C within a ±0.1mm range. Under these operating conditions, the maximum thermally induced displacement at the center was 0.196mm.

[0054] The observation window is 0.5m square. Figure 3 Describing the temperature field distribution, it can be read that the temperature in the center of the sample area can stably reach about 752°C. Within the range of ±0.1mm in the center of the sample area, the temperature difference does not exceed 40°C. Figure 4 Describing the strain displacement under heating conditions, the maximum thermally induced displacement of the center can be read as 0.196 mm.

[0055] Example 2

[0056] The transmission electron microscope in-situ high frequency electrical test chip of this embodiment is as follows Figure 5As shown, the basic principle is the same as that of Example 1, except that a symmetrical design is adopted with a narrower width to accommodate sample rods with smaller diameters.

[0057] The above description of the embodiments is intended to facilitate understanding and use of the invention by those skilled in the art. It will be apparent that those skilled in the art can readily make various modifications to these embodiments and apply the general principles described herein to other embodiments without requiring inventive effort. Therefore, the present invention is not limited to the above-described embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of the present invention, without departing from the scope of the present invention, should be within the scope of protection of the present invention.

Claims

1. A thermoelectric integrated transmission electron microscope in-situ high-frequency test chip, characterized in that: include: A silicon substrate having an insulating layer on its surface; A silicon nitride film provided at an observation window position on a silicon substrate; A high-frequency circuit located on the insulating layer on the front side of the silicon substrate comprises a first input electrode and a first grounding electrode, wherein the first input electrode is connected to the sample region through an inverted U-shaped sample parallel resistor; And a heating circuit is located on the insulating layer on one side surface of the silicon substrate, which forms a meandering resistance structure and includes at least one second input electrode and a second grounding electrode.

2. The thermoelectric integrated transmission electron microscope in-situ high-frequency test chip according to claim 1, characterized in that: The first input electrode and the second input electrode each lead out a measurement electrode near the sample end for in-situ signal measurement.

3. The thermoelectric integrated transmission electron microscope in-situ high-frequency test chip according to claim 2, characterized in that: The resistance value of the measuring electrode is 50-75Ω.

4. The thermoelectric integrated transmission electron microscope in-situ high-frequency test chip according to claim 1, characterized in that: The first input electrode, the first ground electrode, the second input electrode, and the second ground electrode are symmetrically designed or asymmetrically designed.

5. The thermoelectric integrated transmission electron microscope in-situ high-frequency test chip according to claim 1, characterized in that: The thickness of the silicon substrate is 100-300 μm, and the thickness of the silicon nitride film is 15-80 nm.

6. The thermoelectric integrated transmission electron microscope in-situ high-frequency test chip according to claim 1, characterized in that: The thickness of the heating circuit and the high-frequency circuit is 20 to 500 nm.

7. The thermoelectric integrated transmission electron microscope in-situ high-frequency test chip according to claim 1, characterized in that: The inverted U-shaped sample parallel resistor is composed of a slender metal wire and has a resistance of 50 to 75Ω.

8. The thermoelectric integrated transmission electron microscope in-situ high-frequency test chip according to claim 1, characterized in that: The thickness of the insulating layer on the front side of the silicon substrate is 1.5 to 5.0 μm.

9. The thermoelectric integrated transmission electron microscope in-situ high-frequency test chip according to claim 1, characterized in that: The heating circuit is composed of Pt.

10. The thermoelectric integrated transmission electron microscope in-situ high-frequency test chip according to claim 1, characterized in that: The high-frequency circuit is composed of Au.

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