A multi-element alloy probe for semiconductor testing and a manufacturing method thereof

Abstract

The present invention provides a multi - element alloy probe for semiconductor testing and a manufacturing method, including the steps of: pressing an alloy material to obtain an alloy sheet with a preset thickness; making alignment holes on each of the alloy sheets, and the alignment holes serve as alignment targets when cutting the tips of the probes; performing semi - etching treatment on the area corresponding to the tips of each alloy sheet after making the alignment holes; cutting the alloy sheets by an ultrafast laser according to the target size of the probes to obtain a plurality of connected probes; and synchronously cutting the alignment cutting support connection points of the plurality of connected probes to obtain a plurality of independent probes. By manufacturing the semiconductor testing probes of the present invention, the limitations of the MEMS probe process on electroplating materials and performance are broken through, and sub - micron processing accuracy of semiconductor testing probes can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of probe card testing, and particularly to a multi - alloy probe for semiconductor testing and a manufacturing method thereof. Background Art

[0002] Wafer Probing semiconductor wafer testing, as a very important link in the semiconductor manufacturing industry, can not only check the manufacturing defects and yield rate of the wafer fab, but also avoid subsequent packaging waste. The probe used in wafer testing is an important functional component for communication between the tester and the chips under test on the wafer.

[0003] Existing probe technologies all originated in the last century. However, due to process limitations, it is very difficult to fabricate a reliable probe card that simultaneously meets the requirements of high density, fine pitch, small size, and good parallelism. Based on MEMS technology, micron - and nano - scale structures with good consistency and high precision can be fabricated in batches. Applying the UV - LIGA technology in MEMS technology to probes can break through the limitations of traditional processes, thus meeting the test requirements such as high - density, fine - pitch array arrangement and high - frequency testing.

[0004] The vast majority of solutions in the industry use the UV - LIGA technology to fabricate vertical probes. However, the disadvantages of this process are complex processes and high equipment requirements, resulting in relatively high costs. Technically, only metals that can be electroplated can be used as materials for fabricating probes, and generally binary alloys such as palladium - cobalt or nickel - cobalt are used. The material selection range is extremely limited, and there are also bottlenecks in the performance of the probes. Another defect of the micro - electromechanical probes fabricated by the UV - LIGA technology is that the process of fabricating a smaller tip structure is more complex and requires the introduction of high - precision CMP and other processes. Summary of the Invention

[0005] The purpose of the present invention is to provide a multi - alloy probe for semiconductor testing and a manufacturing method thereof to solve the above problems.

[0006] The technical solution provided by the present invention is as follows:

[0007] The present invention provides a manufacturing method for a multi - alloy probe for semiconductor testing, including the steps of:

[0008] Pressing an alloy material to obtain a plurality of alloy sheets with a preset thickness;

[0009] Making alignment holes on each of the alloy sheets, and the alignment holes serve as alignment targets when cutting the tips of the probes;

[0010] Performing semi - etching treatment on the area corresponding to the tip of each alloy sheet after making the alignment holes;

[0011] According to the target size of the probe, the alloy sheet is cut by cold laser to obtain a plurality of connected probes;

[0012] Based on the alignment of a plurality of connected probes, the support connection points are synchronously cut to obtain a plurality of independent probes.

[0013] Further preferably, the area of the alloy sheet corresponding to the tip of the needle for each alloy sheet after making alignment holes is semi-etched, including the steps of:

[0014] According to the thickness of the alloy sheet and the size of the preset needle tip, calculate the etching thickness of the alloy sheet. The calculation formula is:

[0015]

[0016] where a is the thickness of the alloy sheet; b is the size of the preset needle tip; c is the etching thickness of the alloy sheet;

[0017] Based on the etching thickness of the alloy sheet, the area of the alloy sheet corresponding to the tip of the needle is semi-etched by copper chloride solution or ferric chloride solution.

[0018] Further preferably, after making alignment holes on each alloy sheet, the following steps are further included:

[0019] Measure the coordinate information of the alignment holes in the X, Y, and Z directions through an alignment calibration system, obtain the actual measured size of the alignment holes based on the coordinate information, and perform compensation calibration on the actual measured size based on the target size.

[0020] Further preferably, before the area of the alloy sheet corresponding to the tip of the needle for each alloy sheet after making alignment holes is semi-etched, the following steps are also included:

[0021] Coat a photoresist on the first surface of the alloy sheet;

[0022] Bake the first surface of the alloy sheet to remove the solvent of the photoresist;

[0023] After baking the first surface of the alloy sheet, perform photolithography on the first surface; the pattern of the photolithography is designed in the shape of the tip of the probe, the overlay accuracy of the photolithography is less than the preset accuracy, and the opening window of the photolithography is larger than the tip;

[0024] After photolithography on the first surface of the alloy sheet, bake and cure the protected area of the photoresist;

[0025] Develop the first surface of the alloy sheet to remove the photoresist of the tip by dissolving the exposed area.

[0026] Further preferably, before the semi-etching treatment is performed on the area of the alloy sheet corresponding to the tip of the needle after each alignment hole is made, the following steps are also included:

[0027] Coat a photoresist on the second side of the alloy sheet;

[0028] Bake the second side of the alloy sheet to remove the solvent of the photoresist;

[0029] After baking the second side of the alloy sheet, perform photolithography on the second side; the pattern of the photolithography is designed in the shape of the tip of the probe, the overlay accuracy of the photolithography is less than a preset accuracy, and the opening of the photolithography is larger than the tip;

[0030] After performing photolithography on the second side of the alloy sheet, bake and cure the protected area of the photoresist;

[0031] Develop the second side of the alloy sheet to remove the photoresist of the tip by dissolving the exposed area.

[0032] Further preferably, before synchronously cutting the alignment cutting support connection points of the plurality of probes based on the connection to obtain a plurality of independent probes, the following steps are also included:

[0033] Perform UV degluing treatment, micro-etching deoxidation treatment, surface hardening treatment, and nickel-palladium-gold plating on the plurality of connected probes in sequence.

[0034] Further preferably, after the semi-etching treatment is performed on the area of the alloy sheet corresponding to the tip of the needle after each alignment hole is made, the following steps are also included:

[0035] Remove the photoresist on the alloy sheet by an alkaline degluing solution.

[0036] Further preferably, making alignment holes on each alloy sheet includes the following steps:

[0037] Based on a preset alignment hole diameter and the size of the preset needle tip, perform laser cutting or etching on the alloy sheet through an alignment system to form the alignment holes.

[0038] Further preferably, after synchronously cutting the alignment cutting support connection points of the plurality of probes based on the connection to obtain a plurality of independent probes, the following steps are also included:

[0039] Perform UV degluing treatment on the plurality of independent probes.

[0040] A multi-alloy probe for semiconductor testing, including: a multi-alloy probe for semiconductor testing manufactured according to the manufacturing method of the multi-alloy probe for semiconductor testing described above.

[0041] The present invention provides a multi - element alloy probe for semiconductor testing and a manufacturing method thereof, which has the following beneficial effects:

[0042] 1) The probe manufacturing method of the present invention has a wide adaptability to probe materials. It is not limited by the material limitations of the electroforming alloy of traditional MEMS probes. The probe body can be obtained by traditional metallurgical methods, and rare elements can be added to form materials with special performance requirements. The materials for manufacturing probes by this process can be pre - treated and strengthened, and have higher fatigue life advantages compared with other MEMS probes with electroplated multi - layer metal structures.

[0043] 2) The probes manufactured by the present invention can fabricate the probe tips quickly and with high precision. The size of the quick tips can be fabricated according to the requirements of the test needle pressure, meeting the strict control requirements for the piercing depth during the piercing test of the ultra - thin aluminum layer of the chip, and providing a stable contact resistance.

[0044] 3) The present invention uses picosecond laser and femtosecond cold laser to cut the probe body, which can ensure that the mechanical properties of the probe body metal are not reduced due to the thermal effect of processing, meeting the high - precision processing requirements of the probe.

[0045] 4) The process of the present invention is suitable for batch production of probes. Hundreds of high - precision probes can be fabricated in groups, and the main processes are completed by automated equipment, so the production cost of the probes is lower.

[0046] 5) The production cycle of the probes by the process of the present invention is short. Probes can be customized according to the requirements of chip products under the condition of meeting the customer's delivery cycle, and it is more suitable to meet the diverse product requirements of customers. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The above characteristics, technical features, advantages and their implementation manners of a multi - element alloy probe for semiconductor testing and a manufacturing method thereof will be further described below in a clear and understandable manner in conjunction with the drawings in the preferred embodiments.

[0048] Figure 1 is a flowchart of an embodiment of a manufacturing method of a multi - element alloy probe for semiconductor testing according to the present invention;

[0049] Figure 2 is a schematic diagram of pressing a sheet of the alloy material of the present invention;

[0050] Figure 3 is a schematic diagram of annealing the alloy sheet of the present invention;

[0051] Figure 4 is a schematic diagram of cutting and separating the probe of the present invention;

[0052] Figure 5 is a side view of applying photoresist to the alloy sheet of the present invention;

[0053] Figure 6 is a side view of the semi-etching of the alloy sheet of the present invention;

[0054] Figure 7 is a side view of the degumming of the alloy sheet of the present invention;

[0055] Figure 8 is a front view of the cutting profile of the alloy sheet of the present invention;

[0056] Figure 9 is a schematic diagram of the micro-etching and deoxidation treatment of the alloy sheet of the present invention;

[0057] Figure 10 is a schematic diagram of the independent probe of the present invention. Detailed implementation manners

[0058] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will describe the specific implementation manners of the present invention with reference to the accompanying drawings. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings, and other implementation manners can be obtained.

[0059] To simplify the drawings, only the parts related to the present invention are schematically shown in each drawing, and they do not represent the actual structure of the product. In addition, to simplify the drawings for easy understanding, in some drawings, for components with the same structure or function, only one of them is schematically shown, or only one of them is marked. In this article, "one" not only means "only this one", but also means "more than one" situation.

[0060] An embodiment of the present invention, as Figure 1 shown, a method for manufacturing a multi-element alloy probe for semiconductor testing includes the steps:

[0061] S100 Press the alloy material to obtain a plurality of alloy sheets with a preset thickness.

[0062] Specifically, the alloy material includes a copper-silver alloy with a diameter of 0.3 mm. Among them, the silver content in the copper-silver alloy is 1% to 10%, the copper content is 90% to 99%, and the tensile strength of the alloy material is 400 to 1500 Mpa.

[0063] Of course, other alloy copper-magnesium alloys, palladium alloys, nickel alloys, etc. can all meet the mechanical property requirements for manufacturing the probe. The alloy material selected in this embodiment belongs to the preferred alloy material.

[0064] Exemplarily, as Figure 2As shown in the figure, a four-axis metal press is used to press a copper-silver alloy material with a diameter of 0.3 mm. After 4 to 6 pressings, a copper-silver metal sheet (alloy sheet) with the designed thickness (preset thickness) is obtained.

[0065] Among them, the thickness of the alloy sheet is 30 - 100 um, which meets the size requirements of existing wafer-level chip test probes.

[0066] In this embodiment, the metal material is stretched and rolled to meet the thickness requirements of the probe design. After rolling, the metal material has strong stress, and there is a large amount of stress remaining after the probe is processed and formed. Under the condition of ensuring that the mechanical properties of the probe metal material do not decline, the metal sheet of the probe is annealed and flattened.

[0067] Exemplarily, as Figure 3 shown, the metal sheets are stacked in an annealing fixture and annealed in a vacuum annealing furnace at 450 °C for 2 hours. After annealing, there is no oxidation on the surface of the material, and the flatness error remains at 10 um per square centimeter size to ensure that the precision error after probe processing is controlled within 10 um.

[0068] S200 Make alignment holes on each of the alloy sheets, and the alignment holes serve as alignment targets when cutting the tips of the probes.

[0069] Specifically, the preset alignment hole diameter is 0.1 - 1 mm.

[0070] Exemplarily, attach the metal material to the processing platform. When making the alignment target, use high-precision laser cutting to make alignment holes as the alignment target. This alignment target hole provides an alignment system for subsequent processes such as lithography and cutting. Mechanical processing, etching and other processes can also be used to make the alignment target.

[0071] S300 Perform semi-etching on the area corresponding to the tip of each alloy sheet after making the alignment holes.

[0072] Specifically, the high-precision tip of the probe is the key part of the probe. At this time, perform semi-etching on the key part of the probe, and use copper chloride solution or ferric chloride solution for semi-etching.

[0073] Of course, since the alignment target has been made in the above steps, during semi-etching, based on the alignment target, semi-etching can be performed more accurately, avoiding the problem of low tip precision caused by low precision of the semi-etched area. The method of this embodiment can obtain a tip with higher precision.

[0074] Among them, the single-sided etching amount is controlled at 10 - 15 um to reduce the area of the tip after the probe is cut.

[0075] This process, in combination with the cold laser cutting process, can be used to fabricate a probe tip structure with high precision that meets the test requirements, without the need for mechanical machining or grinding of the probe tip. It is not limited to dry etching, laser etching, or other etching processes in the etching method.

[0076] S400 According to the target size of the probe, the alloy sheet is cut by cold laser to obtain a plurality of the connected probes.

[0077] Specifically, the alloy sheet is cut by cold laser based on the alignment holes to obtain the tip. According to the target size of the main body of the probe, a plurality of the connected probes are obtained by laser cutting.

[0078] Among them, the cold laser includes femtosecond, picosecond, etc.

[0079] Exemplarily, the probe main body is cut by laser according to the design drawing, using a femtosecond laser with a laser wavelength of 355 nm, a laser pulse width of less than 350 um, a laser frequency of 650 KHz, a power of 5 W, and a speed of 500 mm / s. The tolerance after laser cutting is + / -5 um.

[0080] Among them, the probe main body can be cut by an ultrashort laser, and the probe can be quickly processed under the condition of not affecting the mechanical properties of the alloy material of the probe.

[0081] S500 Based on the alignment cutting of the support connection points of the plurality of the connected probes, synchronous cutting is performed to obtain a plurality of independent probes.

[0082] Specifically, the probes are cut and separated, and the support connection points are cut in alignment to separate the probes to obtain independent probes. A femtosecond laser with a laser wavelength of 300 nm, a laser pulse width of less than 200 um, a laser frequency of 350 KHz, a power of 3 W, and a speed of 200 mm / s is used for processing. The tolerance after laser cutting is + / -2 um.

[0083] In this embodiment, as Figure 4 shown, when cutting the probe connection ribs in the part other than the tip, the batch of probes are separated by cutting the support points in alignment to obtain a batch of independent probes.

[0084] The process, main structure, and main body of the probe of the present invention adopt the MEMS process and the high-precision femtosecond cold laser cutting technology, which can quickly customize the probe tip according to customer requirements. The processing accuracy of the probe elastomer is high (+ / -2 um), which can ensure stable contact impedance under a small probe needle pressure (force less than 3 gf), and can meet the diverse requirements of the probe needle pressure for the aluminum-type PAD chip test; the processing process has good stability for metal materials and stable mechanical properties, which can ensure a high mechanical fatigue life of the probe.

[0085] Compared with traditional MEMS electroformed tip probes, the present invention has fewer process steps, without multiple lithography-electroforming-grinding cycles. The processing cycle can be completed within one week, and it has significant cost advantages. At the same time, high-precision probes can be mass-produced, further shortening the production cycle and reducing costs.

[0086] Example Two

[0087] Based on the above embodiments, the parts that are the same as those in the above embodiments will not be elaborated one by one in this embodiment. This embodiment provides a method for fabricating a multi-alloy probe for semiconductor testing, including the steps:

[0088] S100 Press the alloy material to obtain multiple alloy sheets with a preset thickness. Exemplarily, it includes the steps:

[0089] S01: Use a four-axis metal press to press a copper-silver alloy material with a diameter of 0.3 mm. After 4-6 pressings, a copper-silver metal sheet with the designed thickness is obtained. The thickness of the alloy sheet after pressing is 30-100 um, and this thickness meets the size requirements of existing wafer-level chip test probes.

[0090] Among them, the silver content in the copper-silver alloy is 1%-10%, the copper content is 90%-99%, and the tensile strength of the alloy is 400-1500 Mpa. This thickness meets the size requirements of existing wafer-level chip test probes. Other alloys such as copper-magnesium alloy, palladium alloy, nickel alloy, etc. can all meet the mechanical property requirements for fabricating the probes.

[0091] S02: Stretch and roll the metal material to meet the thickness requirement of the probe design. After rolling, there is strong stress in the metal material, and there is a large amount of stress remaining after the probe is processed into shape. Under the condition of ensuring that the mechanical properties of the probe metal material do not decline, the probe is annealed and flattened. Stack the metal sheets in an annealing fixture and anneal them in a vacuum annealing furnace at 450°C for 2 hours. After annealing, there is no oxidation on the surface of the material, and the flatness error remains within 10 um per square centimeter in size, so as to ensure that the precision error after probe processing is controlled within 10 um.

[0092] S200 Make alignment holes on each of the alloy sheets. The alignment holes serve as alignment targets when cutting the tips of the probes, including the steps:

[0093] Based on a preset alignment hole diameter and the size of the preset tip, use an alignment system to laser-cut or etch the alloy sheet to form the alignment holes.

[0094] After making the alignment holes on each of the alloy sheets, it further includes the steps:

[0095] Measure the coordinate information of the alignment holes in the X, Y, and Z directions through an alignment calibration system, obtain the actual measured size of the alignment holes based on the coordinate information, and perform compensation calibration on the actual measured size based on the target size.

[0096] Exemplarily, S03: Attach the metal material to the processing platform. Make an alignment target, use high-precision laser cutting to make alignment holes as the target, and the alignment hole diameter is 0.1 - 1 mm. This alignment target hole provides an alignment system for subsequent processes such as lithography. Mechanical processing, etching, and other processes can also be used to make the alignment target.

[0097] Attach the metal material to the processing platform. Make an alignment target, use high-precision laser cutting to make alignment holes as the target, and the alignment hole diameter is 0.1 - 1 mm. After making the alignment target, use a 3 - coordinate measuring device (a general measuring device used to measure the dimensions and positions in the X, Y, and Z directions) to measure the hole position accuracy, and the position accuracy requirement is controlled within plus or minus 2 μm. And perform compensation calibration by comparing the actual measured size with the designed size. This alignment target hole provides an alignment system for subsequent processes such as lithography. Mechanical processing, etching, and other processes can also be used to make the alignment target.

[0098] Before the semi - etching treatment of the area corresponding to the tip of each alloy sheet after making the alignment holes in step S300, it further includes:

[0099] Coat photoresist on the first side of the alloy sheet;

[0100] Bake the first side of the alloy sheet to remove the solvent of the photoresist;

[0101] After baking the first side of the alloy sheet, perform lithography on the first side; the pattern of the lithography is designed in the shape of the tip of the probe, the overlay accuracy of the lithography is less than the preset accuracy, and the opening of the lithography is larger than the tip;

[0102] After lithography on the first side of the alloy sheet, bake and cure the protected area of the photoresist;

[0103] Develop the first side of the alloy sheet to remove the photoresist of the tip by dissolving the exposed area.

[0104] Before the semi - etching treatment of the area corresponding to the tip of each alloy sheet after making the alignment holes in step S300, it further includes:

[0105] Coat photoresist on the second side of the alloy sheet;

[0106] Bake the second side of the alloy sheet to remove the solvent of the photoresist;

[0107] After baking the second side of the alloy sheet, lithography is performed on the second side; the pattern of the lithography is designed in the shape of the tip of the probe, the overlay accuracy of the lithography is less than a preset accuracy, and the opening window of the lithography is larger than the tip;

[0108] After lithography on the second side of the alloy sheet, the protective area of the photoresist is baked and cured;

[0109] Develop the second side of the alloy sheet to remove the photoresist of the tip by dissolving the exposed area.

[0110] Exemplarily, as Figure 5 shown, it specifically includes the following steps:

[0111] S04: Coat AZ4620 photoresist on the first side of the sheet. The function of this photoresist is to protect the non-etched area. The flow rate of the glue spray head is 5 ml / min; the platform rotation speed is 1200 Rpm, and the coating thickness is 5 ± 0.5 um. It is not limited to using any photoresist that meets the requirements.

[0112] S05: Pre-bake the first side. Remove the solvent in the photoresist, enhance the adhesion, and release the internal stress in the photoresist film. Bake at a constant temperature of 80 °C in the oven for 10 minutes.

[0113] S06: Lithography on the first side. The lithography pattern is designed in the shape of the probe tip. The overlay accuracy of the lithography is less than 1.5 um, and the opening window of the lithography is 5 - 10 um larger than the design size of the needle head.

[0114] S07: Post-bake and cure the first side. Cure the protective area of the photoresist. Bake at a constant temperature of 130 °C in the oven for 2 minutes.

[0115] S08: Develop the first side to remove the photoresist layer of the needle head by dissolving the exposed area. The de-glueing temperature range is 21 - 23 °C, and the error is maintained at ±0.5 °.

[0116] S09: Process the second side, and the steps are the same as S04 - S08.

[0117] S300: Perform semi-etching treatment on the area of each alloy sheet corresponding to the tip after making the alignment holes, including the steps:

[0118] According to the thickness of the alloy sheet and the size of the preset tip, calculate the etching thickness of the alloy sheet. The calculation formula is:

[0119]

[0120] where a is the thickness of the alloy sheet; b is the size of the preset tip; c is the etching thickness of the alloy sheet;

[0121] Perform semi-etching on the area corresponding to the tip of the alloy sheet based on the etching thickness of the alloy sheet using a copper chloride solution or a ferric chloride solution.

[0122] After performing semi-etching treatment on the area corresponding to the tip of the alloy sheet for each fabricated alignment hole, the method further includes the step of removing the photoresist on the alloy sheet using an alkaline photoresist stripper.

[0123] Specifically, as Figure 6 shown, S10: Perform semi-etching on the key parts of the probe, use a copper chloride solution or a ferric chloride solution for semi-etching, control the single-sided etching amount to be 10 - 15 μm, and reduce the area of the tip after probe cutting.

[0124] Exemplarily, perform semi-etching on the key parts of the probe, and use a copper chloride solution or a ferric chloride solution for semi-etching.

[0125] In this embodiment, the thickness a of the material before processing is 30 - 50 μm (micrometers), the tip size b required for general test probes is 10 - 20 micrometers, the material etching thickness is (a - b) / 2, and the laser cutting controls the tip size to be c (10 - 20 μm).

[0126] This process, in combination with the cold laser cutting process, can be used to fabricate a probe tip structure that meets the test requirements without the need for mechanical processing or grinding of the probe tip. It is not limited to etching methods such as dry etching and laser etching, and other etching processes.

[0127] In this embodiment, as Figure 7 shown, it further includes: S11. Photoresist removal, completely removing the photoresist using an alkaline photoresist stripper.

[0128] In this embodiment, step S400 cuts the alloy sheet by cold laser according to the target size of the probe to obtain a plurality of connected probes.

[0129] Specifically, it includes:

[0130] As Figure 4 、 8 shown, S12: Cut the probe body using a laser according to the design drawing, use a laser wavelength of 355 nm, a laser pulse width less than 350 μm, a laser frequency of 650 KHz, a power of 5 W, and a femtosecond with a speed of 500 mm / s for processing. The tolerance after laser cutting is + / - 5 μm.

[0131] Use femtosecond, picosecond, etc. cold laser cutting. Ultra-short laser cutting of the probe body can quickly process the probe under the condition of not affecting the mechanical properties of the probe alloy material.

[0132] Before synchronously cutting the alignment cutting support connection points of the multiple probes based on the connection in step S500 to obtain multiple independent probes, the following steps are further included:

[0133] The multiple connected probes are successively subjected to UV de-gluing treatment, micro-etching de-oxidation treatment, surface hardening treatment, and nickel-palladium-gold plating.

[0134] Specifically, it includes: S13: UV de-gluing. Use UV light with a power of 800W to irradiate for 10s to remove the blue film.

[0135] S14: Micro-etching de-oxidation treatment of the probes. Immerse the probes in ultrasonic waves of 2-5% dilute sulfuric acid and clean for 30 seconds to remove cutting oxidation and burrs. As Figure 9 shown.

[0136] In this embodiment, by successively subjecting the probes to UV de-gluing treatment, micro-etching de-oxidation treatment, surface hardening treatment, and nickel-palladium-gold plating, the stability of the needles is improved and the contact sensitivity is enhanced.

[0137] The step of synchronously cutting the alignment cutting support connection points of the multiple probes based on the connection in step S500 to obtain multiple independent probes includes:

[0138] S16, depositing a titanium dioxide insulating film on the non-conductive functional area of the probe using vacuum magnetron sputtering PVD coating, with a deposition thickness of 100nm. Before depositing the insulating film, use a jig to shield the probe tip and tail. First, coat the first side with 100nm of the film. This insulating film can also be made of other metal oxides.

[0139] In this embodiment, through this step, the surface insulation of the needles is achieved to prevent short circuits between the needles. At the same time, using oxides to make the insulating layer can reduce the influence of general insulating coatings on the mechanical properties of the probes.

[0140] S17, cutting and separating the probes, and synchronously cutting the alignment cutting support connection points to separate the probes to obtain independent probes. Use femtosecond laser with a laser wavelength of 300nm, a laser pulse width less than 200um, a laser frequency of 350KHz, a power of 3W, and a speed of 200mm / s for processing. After laser cutting, the tolerance is + / -2um. As Figure 4 shown.

[0141] Further preferably, after synchronously cutting the alignment cutting support connection points of the multiple probes based on the connection to obtain multiple independent probes, the following steps are further included:

[0142] Performing UV de-gluing treatment on the multiple independent probes.

[0143] Specifically, it includes: S18: UV glue removal. Use UV light with a power of 800W to irradiate for 10s to remove the blue film. Remove the probe to form a finished product. As Figure 10 shown.

[0144] In this embodiment, through a MEMS probe improvement manufacturing process, through alignment, cutting, and combined with semi-etching of the tip part, high-precision probes are obtained for semiconductor testing.

[0145] The probe manufactured by the present invention has a wide adaptability to probe materials and does not need to be limited by the material limitations of the electroformed alloy of traditional MEMS probes. The probe body can be obtained by traditional metallurgical methods, and rare elements can be added to form materials with special performance requirements. The probe manufactured by the present invention can quickly and highly precisely manufacture the tip of the probe, and can manufacture the size of the quick tip according to the requirements of the test needle pressure, meet the strict control requirements for the piercing depth during the piercing test of the ultra-thin aluminum layer of the chip, and provide a stable contact resistance. The present invention uses picosecond laser and femtosecond cold laser to cut the probe body, which can ensure that the metal mechanical properties of the probe body are not reduced due to the thermal effect of processing, and meet the high-precision processing requirements of the probe.

[0146] Embodiment 3

[0147] A multi-alloy probe for semiconductor testing, including: a multi-alloy probe for semiconductor testing manufactured according to the manufacturing method of the multi-alloy probe for semiconductor testing described above.

[0148] Specifically, as Figure 10 shown, it can be seen from left to right that the structure of the probe includes: a pointed tip with a contact surface smaller than the needle body, a probe elastic body, and a needle tail with a limiting function.

[0149] The probe manufactured by the present invention has a wide adaptability to probe materials and does not need to be limited by the material limitations of the electroformed alloy of traditional MEMS probes. The probe body can be obtained by traditional metallurgical methods, and rare elements can be added to form materials with special performance requirements. The probe manufactured by the present invention can quickly and highly precisely manufacture the tip of the probe, and can manufacture the size of the quick tip according to the requirements of the test needle pressure, meet the strict control requirements for the piercing depth during the piercing test of the ultra-thin aluminum layer of the chip, and provide a stable contact resistance. The present invention uses picosecond laser and femtosecond cold laser to cut the probe body, which can ensure that the metal mechanical properties of the probe body are not reduced due to the thermal effect of processing, and meet the high-precision processing requirements of the probe.

[0150] It should be noted that the above embodiments can be freely combined as needed. The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and retouches can still be made, and these improvements and retouches should also be regarded as the protection scope of the present invention.

Claims

1. A method for fabricating a multi - element alloy probe for semiconductor testing, characterized in that, Including the steps: Press the alloy material into tablets to obtain multiple alloy sheets with a preset thickness; Make alignment holes on each of the alloy sheets, and the alignment holes serve as alignment targets when the tip of the cutting probe; Perform photolithography on the alloy sheets to determine the area of the semi-etching process and form the probe tip structure; Based on the alignment holes, perform semi-etching on the area corresponding to the tip of each alloy sheet after making the alignment holes; According to the target size of the probe, cut the alloy sheets by ultrafast laser to obtain multiple connected probes; Synchronously cut the alignment cutting support connection points of the multiple connected probes to obtain multiple independent probes; Wherein, the semi-etching process includes: Calculate the etching thickness of the alloy sheet according to the thickness of the alloy sheet and the size of the preset tip. The calculation formula is: Wherein, a is the thickness of the alloy sheet; b is the size of the preset tip; c is the etching thickness of the alloy sheet; Perform semi-etching on the area corresponding to the tip in the alloy sheet based on the etching thickness of the alloy sheet by copper chloride solution or ferric chloride solution.

2. The method for fabricating a multi-alloy probe for semiconductor testing according to claim 1, wherein, After making alignment holes on each of the alloy sheets, it further includes the steps: Measure the coordinate information of the alignment holes in the X, Y, and Z directions through an alignment calibration system, obtain the actual measured size of the alignment holes based on the coordinate information, and perform compensation calibration on the actual measured size based on the target size.

3. The manufacturing method of a multi - element alloy probe for semiconductor testing according to claim 1, characterized in that, Before performing semi-etching on the area corresponding to the tip of each alloy sheet after making the alignment holes, it further includes: Coat photoresist on the first surface of the alloy sheet; Bake the first surface of the alloy sheet to remove the solvent of the photoresist; After baking the first surface of the alloy sheet, perform photolithography on the first surface; the pattern of the photolithography is designed in the shape of the tip of the probe, the overlay accuracy of the photolithography is less than the preset accuracy, and the opening of the photolithography is larger than the tip; After photolithography on the first surface of the alloy sheet, bake and cure the protected area of the photoresist; Develop the first surface of the alloy sheet to remove the photoresist of the tip by dissolving the exposed area.

4. A method for fabricating a multi-alloy probe for semiconductor testing according to claim 3, wherein, Before performing semi-etching on the area corresponding to the tip of each alloy sheet after making the alignment holes, it further includes: Coat photoresist on the second surface of the alloy sheet; Bake the second surface of the alloy sheet to remove the solvent of the photoresist; After baking the second surface of the alloy sheet, perform photolithography on the second surface; the pattern of the photolithography is designed in the shape of the tip of the probe, the overlay accuracy of the photolithography is less than the preset accuracy, and the opening of the photolithography is larger than the tip; After photolithography on the second surface of the alloy sheet, bake and cure the protected area of the photoresist; Develop the second surface of the alloy sheet to remove the photoresist of the tip by dissolving the exposed area.

5. A method for fabricating a multi - element alloy probe for semiconductor testing according to claim 1, wherein, Before synchronously cutting the alignment cutting support connection points of the multiple connected probes to obtain multiple independent probes, it further includes: Successively perform UV degluing treatment, micro-etching deoxidation treatment, surface hardening treatment, and nickel-palladium-gold plating on the multiple connected probes.

6. A method for fabricating a multi-alloy probe for semiconductor testing according to any one of claims 1 to 5, characterized in that, After performing semi-etching treatment on the area of the alloy sheet corresponding to the tip of the needle after making alignment holes for each, the method further includes the step of: Removing the photoresist on the alloy sheet by an alkaline degluing solution.

7. A method for fabricating a multi - element alloy probe for semiconductor testing according to claim 6, wherein, Making alignment holes on each of the alloy sheets includes the steps of: Based on a preset alignment hole diameter and the size of the preset needle tip, performing laser cutting or etching on the alloy sheet through an alignment system to form the alignment holes.

8. A method for manufacturing a multi-alloy probe for semiconductor testing according to claim 7, characterized in that, After synchronously cutting the alignment cutting support connection points of the multiple connected probes to obtain multiple independent probes, it further includes: Performing UV degluing treatment on the multiple independent probes.

9. A multi-alloy probe for semiconductor testing, characterized in that, Including: A multi-element alloy probe for semiconductor testing manufactured by the method for manufacturing a multi-element alloy probe for semiconductor testing according to any one of claims 1 to 8.

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