A suspended island micro-electro-mechanical system thermoelectric performance testing device and a preparation method thereof

Abstract

The present disclosure provides a kind of overhanging island micro-electro-mechanical system thermoelectric performance testing device and preparation method, which can be applied to the technical field of semiconductor device, the thermoelectric performance testing device includes: substrate;Overhanging island structure includes first overhanging island, center overhanging island, third overhanging island, first overhanging island and second overhanging island are symmetrically suspended on the substrate;A plurality of first metal components are arranged on the first overhanging island, the center overhanging island and the second overhanging island;Wherein, in the case where the target to be measured is placed between the first overhanging island and the center overhanging island, the first signal is obtained by the first metal component corresponding to the first overhanging island, the second signal is obtained by the second metal component corresponding to the second overhanging island, the first signal and the second signal are differentially calculated, and the thermoelectric performance test result of the target to be measured is determined based on the result of differential calculation.

Description

Technical Field

[0001] This disclosure relates to the field of semiconductor device technology, and more specifically, to a thermoelectric performance testing device for a suspended island microelectromechanical system and its fabrication method. Background Technology

[0002] Micro-Electro-Mechanical Systems (MEMS) technology, as a crucial pillar of modern science and technology, has demonstrated unique advantages and broad application prospects in numerous fields. With continuous technological advancements, the size of MEMS devices continues to shrink, gradually entering the micro- and nano-scale domain. However, this size reduction has also brought about a series of new challenges, particularly the profound impact of the thermal transport properties of nanomaterials on the reliability and efficiency of electronic devices and systems. At the micro- and nano-scale, the thermal conduction mechanisms of materials differ significantly from those at the macroscopic scale, making phenomena such as quantum effects and phonon scattering particularly prominent. These factors make it difficult to directly apply traditional thermal management methods and theories to MEMS devices.

[0003] Based on this, researchers have proposed suspended MEMS devices to meet the needs of MEMS technology development. However, existing suspended MEMS thermoelectric testing devices still have many problems in terms of fabrication process, testing accuracy, stability and applicability. Summary of the Invention

[0004] (a) Technical problems to be solved

[0005] This disclosure provides a thermoelectric performance testing device for a suspended island microelectromechanical system and its fabrication method, which at least partially solves one of the above-mentioned technical problems.

[0006] (II) Technical Solution

[0007] According to a first aspect of this disclosure, a device for testing the thermoelectric performance of a suspended island microelectromechanical system is provided, comprising: a substrate; a suspended island structure including a first suspended island, a central suspended island, and a third suspended island, wherein the first suspended island and the second suspended island are symmetrically suspended on the substrate about the central suspended island; and a plurality of first metal components, one of which is disposed on each of the first suspended island, the central suspended island, and the second suspended island; wherein, when the target to be tested is placed between the first suspended island and the central suspended island, a first signal is acquired through the first metal component corresponding to the first suspended island, and a second signal is acquired through the second metal component corresponding to the second suspended island; differential calculation is performed on the first signal and the second signal; and the thermoelectric performance test result of the target to be tested is determined based on the result of the differential calculation.

[0008] Optionally, the first signal is the resistance information of the first metal component on the first suspended island, and the second signal is the resistance information of the first metal component on the second suspended island; the thermoelectric performance test result of the target under test is determined based on the result of differential calculation, including: determining the temperature rise information of the first suspended island based on the result of differential calculation, and determining the thermoelectric performance test result of the target under test based on the temperature rise information.

[0009] Optionally, the suspended island structure further includes a silicon nitride film, each suspended island including a silicon nitride film, and a first metal component disposed within the silicon nitride film.

[0010] Optionally, the device further includes: a cantilever connected to the suspended island and the substrate respectively, for suspending the silicon nitride film in the suspended island on the substrate; and a plurality of second metal components, one of which is provided for each suspended island, the second components being located on the substrate and the cantilever, for assisting the first metal component in performing thermoelectric performance testing on the target under test.

[0011] Optionally, the first suspended island, the central suspended island, and the second suspended island are arranged at equal intervals; the first suspended island and the central suspended island are mirror-symmetric; the second suspended island and the first suspended island are mirror-symmetric.

[0012] Optionally, each suspended island is provided with two cantilever groups, which are symmetrically arranged on both sides of the suspended island. Each cantilever group has four cantilever arms, which are evenly spaced.

[0013] Optionally, the first metal component includes: a metal coil disposed within the silicon nitride film of the suspended island; and a metal wire disposed on the silicon nitride film of the suspended island.

[0014] Optionally, the second metal component includes: a metal electrode disposed on a substrate; and a metal lead disposed on a cantilever for connecting the metal wire, the metal coil, and the metal electrode.

[0015] Optionally, the metal leads correspond to the cantilever, with one metal lead provided on each cantilever, and each metal lead being connected to a corresponding metal electrode; wherein, one metal lead in each cantilever group is used to connect the metal wire and the metal electrode, and the other three metal leads are used to connect the metal coil and the metal electrode.

[0016] According to a second aspect of this disclosure, a method for fabricating a suspended island microelectromechanical system thermoelectric performance testing device is provided. The method includes: growing a silicon nitride thin film on a substrate surface; growing a metal component on the surface of the silicon nitride thin film; etching a portion of the silicon nitride thin film to form a suspended island structure and a cantilever structure; and etching the substrate to obtain the testing device.

[0017] (III) Beneficial Effects

[0018] The thermoelectric performance testing device for suspended island microelectromechanical systems provided in this disclosure has at least the following beneficial effects:

[0019] In the suspended island structure, three symmetrical suspended islands are set up. The physical environment of the suspended islands on both sides is theoretically the same, and the electrical environment in the differential measurement circuit is the same. Therefore, by performing differential measurement on the two suspended islands, the influence of ambient temperature fluctuations and power supply noise on thermoelectric performance testing can be effectively removed, thereby improving the testing accuracy of thermoelectric performance. Attached Figure Description

[0020] The above and other objects, features and advantages of this disclosure will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0021] Figure 1 This schematic diagram illustrates the overall structure of a suspended island microelectromechanical system thermoelectric performance testing device provided in an embodiment of this disclosure.

[0022] Figure 2 The schematic diagram shows a top view of a suspended island microelectromechanical system thermoelectric performance testing device provided in an embodiment of the present disclosure;

[0023] Figure 3 The schematic diagram illustrates the center lines of the suspended island microelectromechanical system thermoelectric performance testing device according to an embodiment of the present disclosure;

[0024] Figure 4 This schematically illustrates the thermoelectric performance testing device for a suspended island microelectromechanical system in an embodiment of this disclosure. Figure 1 Schematic diagram of the cross-sectional structure along line AA;

[0025] Figure 5 The schematic diagram illustrates the principle of thermoelectric performance testing based on the suspended island microelectromechanical system thermoelectric performance testing device provided in the embodiments of this disclosure;

[0026] Figure 6 A flowchart illustrating a method for fabricating a thermoelectric performance testing device for a suspended island microelectromechanical system according to an embodiment of the present disclosure is shown.

[0027] Figure label:

[0028] 1-Base; 2-Cantilever; 3-Suspended island; 4-First metal component; 5-Second metal component; 41-Metal wire; 42-Metal coil; 51-Metal electrode; 52-Metal lead. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without inventive effort are within the scope of protection of this disclosure.

[0030] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0031] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0032] In the description of this disclosure, it should be understood that the terms "longitudinal", "length", "circumferential", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the subsystem or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure.

[0033] Throughout the accompanying drawings, identical elements are represented by the same or similar reference numerals. Conventional structures or constructions have been omitted where they may cause confusion in understanding this disclosure. Furthermore, the shapes, dimensions, and positional relationships of the components in the drawings do not reflect actual size, scale, or actual positional relationships. Additionally, any reference numerals placed between parentheses in the claims should not be construed as limiting the claims.

[0034] Similarly, to simplify this disclosure and aid in understanding one or more of the various aspects of the disclosure, in the above description of exemplary embodiments of the present disclosure, various features of the present disclosure are sometimes grouped together in a single embodiment, figure, or description thereof. The use of terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refers to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present disclosure. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0035] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this disclosure, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0036] This disclosure provides a thermoelectric performance testing device for a suspended island microelectromechanical system and its fabrication method. Before introducing the technical solution provided by this disclosure, the relevant technologies involved in this disclosure will be explained.

[0037] Thermoelectric testing devices play an irreplaceable role in studying the thermal transport properties of materials and evaluating the thermal performance of devices. Existing suspended MEMS devices mainly improve the accuracy of measuring the thermoelectric properties of materials by reducing heat conduction through the substrate and achieving mechanical isolation through the suspension structure. However, existing suspended MEMS devices still have problems in terms of testing accuracy and stability.

[0038] The inventors of this disclosure have discovered that thermoelectric performance testing is also affected by environmental factors, such as ambient temperature fluctuations and power supply noise, which can all impact the stability of thermoelectric performance testing. Therefore, this disclosure proposes a suspended island MEMS thermoelectric performance testing device that uses differential measurement to eliminate common-mode interference, thereby further improving the testing accuracy and stability of the thermoelectric performance testing device.

[0039] This disclosure provides a device for testing the thermoelectric performance of a suspended island microelectromechanical system (MEMS), comprising: a substrate; a suspended island structure including a first suspended island, a central suspended island, and a third suspended island, wherein the first and second suspended islands are symmetrically suspended on the substrate about the central suspended island; and a plurality of first metal components, one of which is disposed on each of the first, central, and second suspended islands; wherein, when the target to be tested is placed between the first and central suspended islands, a first signal is acquired through the first metal component corresponding to the first suspended island, and a second signal is acquired through the second metal component corresponding to the second suspended island; differential calculation is performed on the first and second signals, and the thermoelectric performance test result of the target to be tested is determined based on the result of the differential calculation.

[0040] Figure 1 The schematic diagram illustrates the overall structure of a suspended island microelectromechanical system thermoelectric performance testing device provided in an embodiment of this disclosure.

[0041] Figure 2 The illustration shows a top view of a suspended island microelectromechanical system thermoelectric performance testing device provided in an embodiment of the present disclosure.

[0042] like Figure 1 , Figure 2 As shown, the suspended island microelectromechanical system thermoelectric performance testing device of this embodiment includes: a substrate 1, a cantilever 2, a suspended island structure, a first metal component 4, and a second metal component 5.

[0043] The substrate 1 serves as the carrier of the entire thermoelectric device, and at least one set of suspended island structures is provided on the substrate 1. Each set of suspended island structures includes at least three suspended islands 3. In the embodiments of this disclosure, three suspended islands 3 are set as a set, and the specific number of sets is not limited in this disclosure. Each suspended island 3 includes a silicon nitride thin film and a first metal component 4. The first metal component 4 is disposed within the silicon nitride thin film, wherein the silicon nitride thin film and the contained first metal component are integrally formed.

[0044] The cantilever 2 is connected to the suspended island 3 and the substrate 1 respectively, and is used to suspend the silicon nitride film in the suspended island on the substrate 1. In this embodiment, six sets of cantilever groups are provided, and each suspended island 3 is provided with two cantilever groups, which are symmetrically arranged on opposite sides of the suspended island. Each suspended island 3 is suspended on the substrate 1 by two sets of cantilever 2, and the three suspended islands are arranged in parallel intervals. Among them, four cantilever 2 are evenly spaced in each cantilever group.

[0045] The number of first metal components 4 corresponds to the number of suspended islands. The first metal components are disposed within the silicon nitride thin film of the suspended island 3. The first metal components 4 are used to perform thermoelectric performance testing on the target under test.

[0046] The number of second metal components 5 corresponds to the number of suspended islands, with one second metal component 5 for each suspended island. The second metal components are located on the substrate and the cantilever, and are used to assist the first metal component in performing thermoelectric performance testing on the target object.

[0047] See Figure 1 and Figure 2 In this embodiment of the disclosure, each set of suspended island structures includes a first suspended island 301, a central suspended island 302, and a second suspended island 303, wherein the central suspended island 302 is located between the first suspended island 301 and the second suspended island 303.

[0048] In some embodiments, the first suspended island, the central suspended island, and the second suspended island are arranged at equal intervals, the first suspended island and the second suspended island are mirror-symmetrical about the first center line, and the second suspended island and the first suspended island are mirror-symmetrical about the second center line.

[0049] Figure 3 The schematic diagram illustrates the center lines of the suspended island microelectromechanical system thermoelectric performance testing device according to an embodiment of the present disclosure.

[0050] like Figure 3 As shown, the first center line 3a is the center line between the first suspended island 301 and the central suspended island, and the second center line 3b is the center line of the suspended island structure. The direction of the first center line 3a is the same as the arrangement direction of the cantilever group corresponding to the suspended island, and the direction of the second center line is the same as the direction of the first center line.

[0051] Figure 4 This schematically illustrates the thermoelectric performance testing device for a suspended island microelectromechanical system in an embodiment of this disclosure. Figure 1 Schematic diagram of the cross-sectional structure along line AA.

[0052] like Figure 4 As shown, the first metal component 4 includes a metal wire 41 and a metal coil 42. The second metal component 5 includes a metal electrode 51 and a metal lead 52.

[0053] A metal coil 42 is disposed within the silicon nitride thin film of the suspended island, a metal wire 41 is disposed on the silicon nitride thin film of the suspended island, and a metal electrode 51 is disposed on the silicon nitride thin film of the substrate 1. Each metal electrode 51 corresponds to one cantilever 2. Metal leads 52 are disposed on the cantilever 2 to connect the metal wire 41, the metal coil 42, and the metal electrode 51. Each metal lead 52 corresponds to one cantilever, and each cantilever has one metal lead. The width of the metal lead 52 is smaller than the width of the cantilever 2.

[0054] In some embodiments, one side of the metal wire 41 on the suspended island is connected to the metal electrode 51 via a metal lead 52 on one of the cantilever arms in the cantilever group corresponding to the suspended island, while one side of the metal coil 42 on the suspended island is connected to the metal electrode 51 via metal leads 52 on the other three cantilever arms in the cantilever group.

[0055] See also Figure 3 In each suspended island, the first metal component 4 is symmetrically arranged about the third center line 3c, and the third center line 3c is perpendicular to the first center line in the direction.

[0056] Optionally, the thickness of the metal coil 42 and the metal lead 52 is less than 300 nm. In this embodiment of the present disclosure, the thickness of the metal coil 42 and the metal lead 52 is 150 nm. In other embodiments, the thickness of the metal coil 42 and the metal lead 52 can be 100 nm, 200 nm, 250 nm, etc. Those skilled in the art can choose according to actual needs, and this disclosure does not impose any restrictions.

[0057] In some embodiments, the first suspended island, the central suspended island, the second suspended island, and the cantilever group connected to each suspended island in each suspended island structure are symmetrically arranged about the second center line 3b. The metal components corresponding to the first suspended island and the metal components corresponding to the second suspended island are also symmetrically arranged about the second center line 3b to ensure that the physical environment of the first suspended island and the second suspended island is exactly the same.

[0058] In one embodiment of this disclosure, the substrate 1 is rectangular. Those skilled in the art can also set the shape of the substrate according to actual needs, and this disclosure does not impose any limitations.

[0059] See Figure 1 , Figure 2 In this embodiment, in addition to forming a silicon nitride film on the upper surface of the substrate with the suspended island structure, a silicon nitride film is also formed on the lower surface of the substrate corresponding to the suspended island structure. The thickness of the silicon nitride film on the upper surface of the substrate is greater than the thickness of the silicon nitride film on the lower surface. In this embodiment, the thickness of the silicon nitride film on the upper surface of the substrate is 700 nm, and the thickness of the silicon nitride film on the lower surface is 350 nm. In other embodiments, the thickness of the silicon nitride film on the upper surface of the substrate can be between 600-800 nm, and the thickness of the silicon nitride film on the lower surface can be between 300-400 nm; no specific limitation is made herein.

[0060] In this embodiment of the disclosure, one end of the cantilever 2 in each cantilever group is connected to the silicon oxide film of the suspended island structure, and the other end is connected to the substrate 1 (during processing, the silicon nitride film of the suspended island structure, the cantilever, and the silicon nitride film on the substrate 1 are integrally formed). The length of the cantilever 2 is 200-500 μm and the width is less than 5 μm.

[0061] In this embodiment, the cantilever 2 has a length of 300 μm and a width of 2 μm. In other embodiments, the length of the cantilever 2 can be 200 μm, 400 μm, or 500 μm, and the width can be 1 μm, 3 μm, or 4 μm, etc. If the length of the cantilever 2 is too short, heat will be easily transferred from the cantilever 2 to the substrate 1, increasing heat loss. If the length of the cantilever 2 is too long, the heat drop on the cantilever 2 will be greater than the heat drop at both ends of the nanomaterial (the target under test), which will reduce the accuracy of the thermoelectric performance test of the nanomaterial (the target under test). The uniform distribution of the cantilever 2 in each cantilever group helps to reduce the stress of the suspended island 3 structure, making it less likely for the cantilever 2 and the suspended island 3 to break.

[0062] Figure 5 The schematic diagram illustrates the principle of thermoelectric performance testing based on the suspended island microelectromechanical system thermoelectric performance testing device provided in the embodiments of this disclosure.

[0063] like Figure 5 As shown, thermoelectric performance testing includes: placing the target under test (i.e., Figure 5 The "sample" is placed between the central suspended island and any other suspended island. The suspended island with the target to be measured is the measurement island, and the suspended island without the target to be measured is the reference island. The central suspended island (i.e., Figure 5 A direct current is applied to the heating island (i.e., the central suspended island) to heat it, creating a temperature difference between the heating island, the measuring island (the suspended island on which the target is placed), and the reference island. Part of the heat generated by the heating island is transferred to the measuring island through the sample, causing the measuring island's temperature to rise.

[0064] The resistance R of the platinum resistance thermometer (i.e., metal coil 42) on the island was calculated and measured. s The resistance value R of the platinum resistance on the reference island ref The difference between them is ΔR=R s -R ref The temperature rise ΔT of the measured island is obtained. Based on ΔT, the thermal conductivity G of the target can be calculated. Finally, the thermal conductivity σ of the sample is calculated by combining the shape of the target.

[0065] Since there is a temperature difference ΔT1 between the two ends of the target under test, a voltage difference ΔV will be caused between the two ends of the sample. The voltage difference between the two ends of the sample is measured by using a metal wire 41. Based on the temperature difference and voltage difference between the two ends of the target under test, the Seebeck coefficient S=ΔV / ΔT1 is calculated, thereby determining the thermoelectric performance of the target under test.

[0066] Taking the placement of the target object between the first floating island and the central floating island as an example, the first floating island is then... Figure 5 The measurement island in the middle, the central suspended island is Figure 5 The heated suspended island in the middle, the second suspended island is Figure 5 The reference island is located between the second and central suspended islands. It should be noted that the target to be measured can also be placed between the second and central suspended islands; this disclosure does not specify a particular location. When the target to be measured is placed between the second and central suspended islands, the second suspended island serves as the measurement island, and the first suspended island serves as the reference island. The target to be measured can be, for example, a nanomaterial, and can be placed between the measurement and heating islands using micro / nano material transfer techniques such as focused ion beam (FIB). Both ends of the target to be measured are in contact with the measurement island and the heating island, respectively.

[0067] A first signal is acquired through the first metal component corresponding to the first suspended island, and a second signal is acquired through the first metal component corresponding to the second suspended island. Differential calculation is performed on the first and second signals, and the thermoelectric performance test result of the target is determined based on the result of the differential calculation. The first signal represents the resistance information of the first metal component in the first suspended island, and the second signal represents the resistance information of the first metal component in the second suspended island. Determining the thermoelectric performance test result of the target based on the differential calculation includes: determining the temperature rise information ΔT of the first suspended island based on the difference between the first and second signals; calculating the thermal conductivity G of the target based on ΔT; and finally calculating the sample thermal conductivity σ by combining the shape of the target.

[0068] This embodiment of the invention employs a measurement scheme that uses a reference suspended island to implement differential measurement at the measurement end. Since the left and right suspended islands are theoretically in the same physical environment and have the same electrical environment in the differential measurement circuit, the effects of ambient temperature fluctuations and power supply noise on the left and right suspended islands are the same. By eliminating the common-mode noise of the reference suspended island and the measurement suspended island through differential measurement, the noise originating from power supply and ambient temperature fluctuations cancels each other out, thereby improving the testing accuracy and precision of the thermoelectric properties of nanomaterials.

[0069] Based on the aforementioned suspended island microelectromechanical system thermoelectric performance testing device, this disclosure also provides a method for fabricating the suspended island microelectromechanical system thermoelectric performance testing device. The following will be combined with... Figure 6 The preparation method is described in detail.

[0070] Figure 6 A flowchart illustrating a method for fabricating a thermoelectric performance testing device for a suspended island microelectromechanical system according to an embodiment of the present disclosure is shown.

[0071] like Figure 6 As shown, the preparation method may include, for example, operations S610 to S640.

[0072] In operation with S610, a silicon nitride thin film is grown on the substrate surface.

[0073] In some embodiments, a silicon nitride thin film can be grown on the upper and lower surfaces of a substrate using low-pressure chemical vapor deposition (LPCVD). The upper silicon nitride thin film grown on the upper surface of the substrate is used to prepare a suspended island structure, and the lower silicon nitride thin film grown on the lower surface of the substrate is used to form an etching window.

[0074] In operation of S620, metal components are grown on the surface of silicon nitride thin film.

[0075] In some embodiments, a first metal component and a second metal component are grown on the surface of an upper silicon nitride thin film.

[0076] First, after defining the required patterns for the metal coil and metal leads using negative photoresist, chromium (Cr) is deposited as an adhesion layer using magnetron sputtering, followed by platinum (Pt). Finally, the layers are stripped in acetone and dried to obtain the metal coil and metal leads of the first metal component 4. In this embodiment, the adhesion layer thickness is 5 nm; in other embodiments, it can be 10 nm, 15 nm, or 25 nm, etc. Second, after defining the required patterns for the metal electrodes using negative photoresist, Cr is deposited as an adhesion layer using magnetron sputtering, followed by gold (Au). Finally, the layers are stripped in acetone. Finally, a silicon nitride passivation layer is grown on the surface of the metal component using plasma-enhanced chemical vapor deposition (PECVD). In this embodiment, the silicon nitride passivation layer thickness is 350 nm; in other embodiments, it can be 300-400 nm.

[0077] In operation S630, certain areas of the silicon nitride thin film are etched to form suspended island structures and cantilever structures.

[0078] In some embodiments, a suspended island structure is obtained by patterning and etching the surface of the upper silicon nitride film using photolithography. A bottom etched window is obtained by patterning and etching the surface of the lower silicon nitride film using photolithography.

[0079] The S640 is used to etch the substrate to obtain the test device.

[0080] In some embodiments, the substrate 1 is etched using a tetramethylammonium hydroxide (TMHA) solution and a hydrogen fluoride (HF) solution until the island structure is completely released, then the residual HF is washed away with deionized water, and finally dried.

[0081] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Without departing from the scope of this disclosure, those skilled in the art can make various substitutions and modifications, all of which should be included within the protection scope of this disclosure.

Claims

1. A thermoelectric performance testing device for a suspended island microelectromechanical system, characterized in that, The device includes: Base; The suspended island structure includes a first suspended island, a central suspended island, and a third suspended island. The first and second suspended islands are symmetrically suspended on the base about the central suspended island. Multiple first metal components are provided, with one first metal component each on the first suspended island, the central suspended island, and the second suspended island; Specifically, when the target to be tested is placed between the first suspended island and the central suspended island, a first signal is obtained through the first metal component corresponding to the first suspended island, and a second signal is obtained through the second metal component corresponding to the second suspended island. Differential calculation is performed on the first signal and the second signal, and the thermoelectric performance test result of the target to be tested is determined based on the result of the differential calculation. Wherein, the first signal is the resistance information of the first metal component on the first suspended island, and the second signal is the resistance information of the first metal component on the second suspended island; the step of determining the thermoelectric performance test result of the target under test based on the differential calculation result includes: determining the temperature rise information of the first suspended island based on the differential calculation result, and determining the thermoelectric performance test result of the target under test based on the temperature rise information.

2. The test device according to claim 1, characterized in that, The suspended island structure also includes: A silicon nitride thin film, each suspended island comprising a silicon nitride thin film, wherein the first metal component is disposed within the silicon nitride thin film.

3. The test device according to claim 2, characterized in that, The device also includes: The cantilever is connected to the suspended island and the substrate respectively, and is used to suspend the silicon nitride film in the suspended island on the substrate. Multiple second metal components are provided, with one second metal component corresponding to each suspended island. The second metal components are located on the substrate and the cantilever, and are used to assist the first metal component in performing thermoelectric performance testing on the target under test.

4. The test device according to claim 1, characterized in that, The first suspended island, the central suspended island, and the second suspended island are arranged at equal intervals; the first suspended island and the central suspended island are mirror images of each other; the second suspended island and the first suspended island are mirror images of each other.

5. The test device according to claim 1, characterized in that, Each suspended island is provided with two cantilever groups, which are symmetrically arranged on both sides of the suspended island. Each cantilever group has four cantilever arms, which are evenly spaced.

6. The test device according to claim 1, characterized in that, The first metal component includes: A metal coil is disposed within a silicon nitride thin film of the suspended island; Metal wires are disposed on the silicon nitride thin film of the suspended island.

7. The test device according to claim 3, characterized in that, The second metal component includes: A metal electrode is disposed on the substrate; Metal leads are provided on the cantilever and are used to connect metal wires, metal coils and metal electrodes.

8. The test device according to claim 6 or 7, characterized in that, The metal leads correspond to the cantilever arms, with one metal lead installed on each cantilever arm, and each metal lead is connected to a corresponding metal electrode. In each cantilever assembly, one metal lead is used to connect the metal conductor to the metal electrode, and the other three metal leads are used to connect the metal coil to the metal electrode.

9. A method for fabricating a thermoelectric performance testing device for a suspended island microelectromechanical system, used to fabricate the thermoelectric performance testing device according to any one of claims 1 to 8, characterized in that, The method includes: A silicon nitride thin film is grown on the substrate surface; Metal components are grown on the surface of the silicon nitride thin film; Etching certain areas in a silicon nitride thin film to form suspended island and cantilever structures; The substrate is etched to obtain the test device.

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