A raman spectroscopy chip test sample holder

Abstract

The present application relates to the technical field of Raman spectrum measurement, and especially to a Raman spectrum method chip test sample holder, which comprises a sample holder body, a chip positioning mechanism, a chip pressing and fixing mechanism and an electrical test mechanism arranged on the sample holder body, the chip positioning mechanism is detachably arranged on the sample holder body through the chip pressing and fixing mechanism, and the electrical test mechanism is symmetrically arranged on both sides of the chip positioning mechanism; wherein the electrical test mechanism comprises a first electrical test interface and a second electrical test interface, the first electrical test interface is used for Raman spectrum detection of the front surface of a chip or the back surface of the chip, and the second electrical test interface is used for Raman spectrum detection of the back surface of the chip or the front surface of the chip. The sample holder can be compatible with Raman spectrum front and back laser tests, realize accurate positioning of laser to an active region, and can synchronously complete optical and electrical parameter measurement.

Description

Technical Field

[0001] This invention relates to the field of Raman spectroscopy measurement technology, and in particular to a Raman spectroscopy chip test sample holder. Background Technology

[0002] With the continuous increase in the integration density of semiconductor chips and the constant rise in operating frequency, the heat flux density generated by the chips during operation increases dramatically. Effective thermal management and temperature monitoring are key to ensuring the stability and reliability of chip performance and extending its service life. Traditional chip temperature detection methods include thermocouples and infrared measurement, but these methods suffer from low accuracy, slow response speed, and difficulty in accurately measuring the internal temperature distribution of the chip.

[0003] In recent years, in-situ Raman spectroscopy has become a research hotspot for micro-area temperature detection due to its advantages such as non-destructive nature, high spatial resolution (micrometer to submicrometer level), non-contact measurement, and no need for special markers. Especially in the temperature characterization of silicon-based special chips on heterogeneous substrates such as silicon-on-carbide (SOS) and silicon-on-diamond (SOD), Raman spectroscopy has demonstrated unique value. However, Raman temperature measurement applications for such special chips must meet the following specific operating conditions: First, due to the difference in thermal conductivity between the chip substrate (such as SiC, diamond) and the top silicon layer, laser heating and Raman spectroscopy testing are often required from both the front and back sides of the chip to obtain complete thermal characteristic parameters; second, Raman excitation must be accurately directed to the active region (channel region) of the chip device to avoid interference from the substrate signal; third, while performing Raman spectroscopy measurements, the in-situ extraction of chip electrical parameters (such as current, voltage, transconductance, etc.) must be completed simultaneously to establish an electro-thermal coupling model.

[0004] Current in-situ Raman spectroscopy for temperature measurement primarily uses sample holders from general in-situ electrical testing methods for Raman spectroscopy measurements, or employs probe stations and other devices for auxiliary optical measurements. The disadvantages of directly using sample holders from other fields for Raman spectroscopy are obvious. Furthermore, these testing stages are typically quite thick and require additional auxiliary devices, lacking consideration in chip fixation and positioning, often leading to inaccurate measurement results due to chip misalignment. In addition, after fixing the sample, performing comparative measurements by laser irradiation on the other side requires disassembling and re-soldering the sample, a complex operation that may even prevent disassembly.

[0005] Therefore, developing a special sample holder specifically designed for special chips such as SOS and SOD, capable of Raman spectroscopy laser testing on both sides, achieving precise laser positioning to the active region, and simultaneously measuring optical and electrical parameters, in order to overcome the aforementioned deficiencies of existing technologies and meet the high-precision, high-efficiency, and multifunctional synchronous testing requirements of Raman spectroscopy temperature measurement for special chips, is a technical problem that urgently needs to be solved in this field.

[0006] In view of this, the present invention is proposed. Summary of the Invention

[0007] The purpose of this invention is to provide a sample holder for Raman spectroscopy chip testing. This sample holder is compatible with Raman spectroscopy front and back laser testing, enables precise laser positioning to the active region, and can simultaneously complete optical and electrical parameter measurements.

[0008] This invention provides a sample holder for Raman spectroscopy chip testing, comprising a sample holder body and a chip positioning mechanism, a chip clamping and fixing mechanism, and an electrical testing mechanism disposed on the sample holder body. The chip positioning mechanism is detachably disposed on the sample holder body via the chip clamping and fixing mechanism, and the electrical testing mechanism is symmetrically disposed on both sides of the chip positioning mechanism. The electrical testing mechanism includes a first electrical testing interface and a second electrical testing interface. The first electrical testing interface is used for Raman spectroscopy detection on the front or back of the chip, and the second electrical testing interface is used for Raman spectroscopy detection on the back or front of the chip.

[0009] As a preferred embodiment of this technical solution, the chip positioning mechanism includes a chip positioning plate, the chip positioning plate having a positioning groove matching the size of the chip to be tested, and a first light-transmitting window being provided at the center of the positioning groove.

[0010] As a preferred embodiment of this technical solution, the positioning groove is provided with a plurality of pads surrounding the outside of the first light-transmitting window, and each pad is provided with a first port.

[0011] As a preferred embodiment of this technical solution, a high-precision positioning reference surface is provided in the positioning groove, and multiple positioning through holes are provided on the edge of the positioning groove, with each positioning through hole corresponding to a second port; The second port is electrically connected to the first port in a one-to-one correspondence, and the second port is connected to either the first electrical test interface or the second electrical test interface.

[0012] As a preferred embodiment of this technical solution, each of the positioning through holes can be detachably fitted with a positioning pin, and based on the fact that multiple positioning pins are arranged in a square symmetrical manner, at least one of the positioning pins is arranged in a position offset manner.

[0013] In a preferred embodiment of this technical solution, the chip clamping and fixing mechanism includes multiple positioning holes, each corresponding to a positioning through hole, and the positioning pin is detachably engaged with the positioning hole.

[0014] As a preferred embodiment of this technical solution, a second light-transmitting window is provided at the axis of the chip clamping and fixing mechanism, and the second light-transmitting window is coaxially arranged with the first light-transmitting window.

[0015] As a preferred embodiment of this technical solution, the dimensions of both the first and second light-transmitting windows are larger than the size of the Raman laser beam spot.

[0016] As a preferred embodiment of this technical solution, the first electrical test interface and the second electrical test interface are arranged in a rotationally symmetrical manner.

[0017] As a preferred embodiment of this technical solution, the first electrical test interface is a Raman spectroscopy detection interface on the front side of the chip, and the second electrical test interface is a Raman spectroscopy detection interface on the back side of the chip; Alternatively, the first electrical test interface may be a Raman spectroscopy detection interface on the back of the chip, and the second electrical test interface may be a Raman spectroscopy detection interface on the front of the chip.

[0018] The Raman spectroscopy chip test sample holder of the present invention has at least the following beneficial effects: 1. The Raman spectroscopy chip test sample holder of this invention adopts an ultra-thin plate-type sample holder body, fundamentally solving the technical problems of insufficient working distance of high numerical aperture objectives, ineffective focusing of Raman excitation light, and low light collection efficiency of scattered signals caused by the large thickness of traditional test stages or probe stages. The ultra-thin plate-type sample holder body of this invention ensures that the Raman spectrometer objective lens can be close to the chip surface to achieve optimal focusing, thereby significantly improving the signal-to-noise ratio and acquisition efficiency of Raman spectral signals, and providing a reliable optical data foundation for high-precision temperature analysis and calculation.

[0019] 2. The chip positioning mechanism and chip clamping and fixing mechanism of this invention ensure a high degree of consistency in the chip's position on the sample holder after each wafer mounting. This precise positioning design guarantees that the Raman excitation laser can accurately and repeatedly irradiate the target active region of the chip device, effectively avoiding the problem of inconsistent spectral signal sources caused by chip position offset.

[0020] 3. This invention achieves double-sided assembly capability of the sample holder body by setting up a first electrical test interface and a second electrical test interface, combined with a through-type bidirectional optical path design of a chip positioning mechanism and a chip clamping and fixing mechanism. During the testing process, when laser heating and Raman detection are required from the back of the chip, there is no need to disassemble the chip or re-solder the wires. Simply flip the chip positioning mechanism and connect it to the outside through another interface to quickly switch to the back-side testing mode. This design greatly simplifies the operation process of front-side and back-side comparison testing of special chips such as SOS and SOD, avoids the risk of physical damage and positioning errors caused by repeated chip disassembly and assembly, and ensures the homogeneity of front-side and back-side testing conditions.

[0021] 4. This invention integrates the chip positioning mechanism, the chip clamping and fixing mechanism, and the electrical testing mechanism into a single unit. While the active region of the chip is precisely irradiated by Raman laser and its spectrum is acquired, the in-situ extraction of the chip's electrical parameters can be simultaneously completed through the electrical testing interface and internal leads, achieving true in-situ joint characterization of multiple physical quantities. Attached Figure Description

[0022] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the sample holder for the Raman spectroscopy chip test of the present invention; Figure 2 This is a schematic diagram of the exploded structure of the sample holder for the Raman spectroscopy chip of the present invention; Figure 3 This is a side view of the sample holder for the Raman spectroscopy chip test of the present invention; Figure 4 This is a schematic diagram of the overall structure of the sample holder for the Raman spectroscopy chip test of the present invention; Figure 5 This is a top view of the sample holder for the Raman spectroscopy chip test of the present invention; Figure 6 This is a circuit diagram of the sample holder for the Raman spectroscopy chip of the present invention.

[0024] Explanation of reference numerals in the attached figures: 1: Sample holder body; 2: First electrical test interface; 3: Second electrical test interface; 4: Chip positioning board; 5: First light-transmitting window; 6: Pad; 7: Positioning pin; 8: Positioning clip hole; 9: Second light-transmitting window; 10: Fastening through hole. Detailed Implementation

[0025] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0027] 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 indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] like Figure 6 As shown, the first aspect of this embodiment provides a Raman spectroscopy chip test sample holder, including a sample holder body 1 and a chip positioning mechanism, a chip clamping and fixing mechanism and an electrical testing mechanism disposed on the sample holder body 1. The chip positioning mechanism is detachably disposed on the sample holder body 1 through the chip clamping and fixing mechanism, and the electrical testing mechanism is symmetrically disposed on both sides of the chip positioning mechanism.

[0029] First, the chip positioning and clamping mechanisms effectively ensure a high degree of consistency in the chip's position on the sample holder after each wafer mounting. This guarantees that the Raman excitation laser can accurately and repeatedly irradiate the target active region of the chip device, effectively avoiding inconsistencies in spectral signal sources caused by chip positional shifts. Second, by integrating the electrical testing mechanism with the chip positioning and clamping mechanisms, while the Raman laser precisely irradiates the active region of the chip and acquires spectra, the in-situ extraction of the chip's electrical parameters can be simultaneously completed through the electrical testing interface and internal leads, achieving true in-situ joint characterization of multiple physical quantities.

[0030] Specifically, the electrical testing mechanism includes a first electrical testing interface 2 and a second electrical testing interface 3, wherein the first electrical testing interface 2 is used for Raman spectroscopy detection on the front or back of the chip, and the second electrical testing interface 3 is used for Raman spectroscopy detection on the back or front of the chip.

[0031] Based on the above technical solution, the sample holder body 1 further adopts an ultra-thin flat plate structure design to ensure that the Raman spectrometer objective lens can achieve accurate focusing within the normal working distance, thus solving the technical pain points of focusing difficulties and low optical signal transmission and reception efficiency caused by the excessive thickness of the existing test stage.

[0032] For example, the thickness of the sample holder body 1 of the present invention is 0.5-5 mm, and preferably 1.6 mm. The material of the sample holder body 1 is preferably a material with characteristics such as weak fluorescence background and high mechanical strength, such as Teflon high-frequency plate, Teflon is polytetrafluoroethylene (PTFE) and other materials.

[0033] The chip positioning mechanism specifically includes a chip positioning plate 4, and the chip positioning plate 4 has a positioning groove that matches the size of the chip to be tested. A first light-transmitting window 5 is provided at the center of the positioning groove so that the Raman light source can be accurately incident on the active area of ​​the chip.

[0034] In a specific embodiment of the present invention, a plurality of pads 6 are arranged around the outside of the first light-transmitting window 5 in the positioning groove so as to fix the chip under test in the positioning groove by means of silver paste. Each pad is provided with a first port, which is arranged directly close to the chip under test and is used to collect the chip's electrical signals and transmit control signals.

[0035] In addition, multiple positioning through holes are formed around the edge of the positioning slot, each with a corresponding second port. These second ports are electrically connected to the first ports in a one-to-one correspondence. This one-to-one connection ensures that the electrical signals from the chip pins are precisely transmitted to the second ports, preventing signal crosstalk caused by messy and intertwined wiring and guaranteeing complete and unbiased transmission of electrical test signals. Furthermore, the second ports extend outwards and connect to either the first electrical test interface 2 or the second electrical test interface 3 for detecting the front or back Raman spectra of the chip under test. The one-to-one connection between the first and second ports forms a fixed signal path, allowing signals from the same set of chips to be simultaneously transmitted to the first electrical test interface 2 for front detection and the second electrical test interface 3 for back detection. When the sample holder is mounted upright for front detection and reversed for back detection, the test mode can be quickly switched without rewiring or changing the wiring, thus meeting the requirements for simultaneous electrical detection of double-sided Raman spectroscopy.

[0036] To further prevent the chip under test from shifting, a positioning pin 7 can be detachably installed in each positioning through hole. The positioning pin 7 is designed to keep the chip under test in the positioning groove, preventing it from shifting, and also serves as a conductive component. Specifically, during use, a uniform clamping force can be applied by the elastic clamping positioning pin 7 to prevent the chip under test from shifting during testing, while avoiding damage to the surface of the chip under test.

[0037] Furthermore, based on the fact that the multiple positioning pins are arranged in a square symmetry, at least one positioning pin is arranged with a position offset, which can effectively prevent misassembly and mistaken installation. Specifically, the position offset arrangement can be selected by offsetting one positioning pin outward by a certain distance, but the present invention does not strictly limit the specific offset distance.

[0038] To further ensure the consistency of the assembly position of the chip under test, a high-precision positioning reference surface is also provided in the positioning slot.

[0039] The chip clamping and fixing mechanism specifically includes multiple positioning holes 8, with each positioning hole 8 corresponding to a positioning through hole. Positioning pins 7 are detachably engaged with the positioning holes 8. That is, by engaging the positioning pins 7 with the positioning holes 8, the chip under test can be clamped, fixed, and electrically connected.

[0040] The present invention does not strictly limit the specific implementation of the positioning pin 7 and the positioning hole 8, but aims to achieve a detachable snap-fit ​​connection between the positioning pin 7 and the positioning hole 8. For example, a purchased cross pin and sensor socket can be used directly.

[0041] Based on the above technical solution, and further preferably, a second light-transmitting window 9 corresponding to the position of the positioning groove is provided at the axis of the chip clamping and fixing mechanism, and the second light-transmitting window 9 is coaxially arranged with the first light-transmitting window 5 to form a through-type bidirectional optical path structure, so that the Raman laser beam can directly irradiate the active area of ​​the chip from the bottom of the sample holder body 1 and collect the Raman signal scattered by the chip. When the chip positioning plate is flipped, the Raman laser beam still directly irradiates the active area of ​​the chip under test from the bottom of the sample holder body 1, realizing the Raman spectrum detection of the back of the chip under test. Specifically, the size of the first light-transmitting window 5 and the second light-transmitting window 9 is larger than the size of the Raman laser beam spot, and when the light-transmitting aperture is 2.5mm-4.5mm, it is smaller than the size of the active area of ​​the chip under test, so as to ensure that the optical path is unobstructed while limiting the range of the test area.

[0042] Regarding the electrical testing mechanism, its corresponding first electrical testing interface 2 or second electrical testing interface 3 is electrically connected to multiple second ports.

[0043] For example, both the first electrical test interface 2 and the second electrical test interface 3 include pins 1 to 12 and pins 13 to 25 (floating). The second ports 1 to 12 are respectively connected to pins 1 to 12 of the first electrical test interface 2 or pins 1 to 12 of the second electrical test interface 3. Raman spectroscopy detection of the front and back sides of the chip under test can be achieved by different connection orders.

[0044] That is, the multiple second ports of the present invention are controlled by two test interfaces, the first electrical test interface 2 and the second electrical test interface 3, supporting front / back Raman detection. During the test, when laser heating and Raman detection are required on the front and back of the chip, the first electrical test interface 2 or the second electrical test interface 3 are used for wiring respectively, without modifying the sample holder structure.

[0045] Specifically, the first electrical test interface 2 and the second electrical test interface 3 are arranged in a rotationally symmetrical layout. Combined with the through-type bidirectional optical path design of the chip positioning mechanism and the chip clamping and fixing mechanism, the sample holder body 1 can be assembled on both sides. When laser heating and Raman detection are required from the back of the chip, the forward and reverse test modes can be quickly switched without disassembling the sample, adapting to bidirectional Raman detection of the chip. Secondly, the rotationally symmetrical layout design of the first electrical test interface 2 and the second electrical test interface 3 specifically solves the pain point of inaccurate sample fixation and positioning in existing test stages, ensuring the consistency of chip assembly position and ensuring that the incident area of ​​the Raman light source and the active area of ​​the chip are precisely aligned.

[0046] The present invention does not strictly limit the specific surface of the chip detected by the first electrical test interface 2 and the second electrical test interface 3.

[0047] For example, the first electrical test interface 2 is the Raman spectroscopy detection interface on the front of the chip, and the second electrical test interface 3 is the Raman spectroscopy detection interface on the back of the chip; Alternatively, the first electrical test interface 2 can be a Raman spectroscopy detection interface on the back of the chip, and the second electrical test interface 3 can be a Raman spectroscopy detection interface on the front of the chip.

[0048] Based on the above technical solution, and further preferably, a fastening through hole 10 is provided at the apex of the sample holder body, chip positioning plate, etc. The fastening through hole 10 can further lock the chip positioning plate 4 to ensure stable and reliable clamping.

[0049] The second aspect of this invention provides a testing procedure for testing a sample holder using the aforementioned Raman spectroscopy chip. The beneficial effects of the second aspect and its various implementations in this invention can be found in the analysis of the beneficial effects of the first aspect and its various implementations, and will not be repeated here.

[0050] Specifically, the testing process is as follows: When it is necessary to perform Raman spectroscopy detection on the front side of the chip under test: First, place the chip under test face up into the positioning slot, and connect the chip electrodes to pad 6 with a flying wire to connect to the external test instrument. The second step is to install the positioning slot of the chip under test onto the chip clamping and fixing mechanism, and then lock and fix it by the clamping and fixing mechanism and the fastening through hole 10. The third step is to start the Raman laser and directly irradiate the active area of ​​the chip under test through the bottom of the sample holder 1. Step 4: Apply a working voltage to the chip under test through the first electrical test interface 2, and the Raman spectrometer collects the Raman signal of the chip's heating area. Simultaneously, the external instrument collects electrical data to achieve in-situ joint testing.

[0051] When it is necessary to perform Raman spectroscopy on the back side of the chip under test: Similar to the front-side test, the difference is that in the second step, the positioning slot is reversed and installed on the chip clamping and fixing mechanism, and then the working voltage is applied to the chip through the second electrical test interface 3.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A sample holder for Raman spectroscopy chip testing, characterized in that, The sample holder includes a sample holder body and a chip positioning mechanism, a chip clamping and fixing mechanism, and an electrical testing mechanism disposed on the sample holder body. The chip positioning mechanism is detachably disposed on the sample holder body via the chip clamping and fixing mechanism, and the electrical testing mechanism is symmetrically disposed on both sides of the chip positioning mechanism. The electrical testing mechanism includes a first electrical testing interface and a second electrical testing interface. The first electrical testing interface is used for Raman spectroscopy detection on the front or back of the chip, and the second electrical testing interface is used for Raman spectroscopy detection on the back or front of the chip.

2. The Raman spectroscopy chip test sample holder according to claim 1, characterized in that, The chip positioning mechanism includes a chip positioning plate, which has a positioning groove that matches the size of the chip to be tested, and a first light-transmitting window at the center of the positioning groove.

3. The Raman spectroscopy chip test sample holder according to claim 2, characterized in that, The positioning groove is surrounded by multiple pads on the outside of the first light-transmitting window, and each pad is provided with a first port.

4. The Raman spectroscopy chip test sample holder according to claim 2, characterized in that, The positioning groove is provided with a high-precision positioning reference surface, and the edge of the positioning groove is provided with multiple positioning through holes, each of which is provided with a second port. The second port is electrically connected to the first port in a one-to-one correspondence, and the second port is connected to either the first electrical test interface or the second electrical test interface.

5. The Raman spectroscopy chip test sample holder according to claim 4, characterized in that, Each of the positioning through holes can be detachably fitted with a positioning pin, and based on the fact that multiple positioning pins are arranged in a square symmetry, at least one of the positioning pins is arranged in a position offset manner.

6. The Raman spectroscopy chip test sample holder according to claim 5, characterized in that, The chip clamping and fixing mechanism includes multiple positioning holes, each corresponding to a positioning through hole, and the positioning pin is detachably engaged with the positioning hole.

7. The Raman spectroscopy chip test sample holder according to claim 5, characterized in that, The chip clamping and fixing mechanism has a second light-transmitting window at its axis, and the second light-transmitting window is coaxially arranged with the first light-transmitting window.

8. The Raman spectroscopy chip test sample holder according to claim 7, characterized in that, The dimensions of both the first and second light-transmitting windows are larger than the size of the Raman laser beam spot.

9. The Raman spectroscopy chip test sample holder according to claim 1, characterized in that, The first electrical test interface and the second electrical test interface are arranged in a rotationally symmetrical manner.

10. The Raman spectroscopy chip test sample holder according to claim 1, characterized in that, The first electrical test interface is the Raman spectroscopy detection interface on the front of the chip, and the second electrical test interface is the Raman spectroscopy detection interface on the back of the chip; Alternatively, the first electrical test interface may be a Raman spectroscopy detection interface on the back of the chip, and the second electrical test interface may be a Raman spectroscopy detection interface on the front of the chip.

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