Parylene coating and stripping methods for micro devices with internal channels and profiled surfaces

Abstract

The present invention provides a method for coating and removing parylene for a micro device with an internal channel and a profiled surface, including forming a mask layer and coating a parylene film layer on the micro device, wherein the peel strength of the mask layer is <1N / mm and the tensile strength is <30Mpa; the micro device is fixed in the through hole of the fixture; the micro device is sandblasted with sodium bicarbonate or dry ice to remove the mask layer and the parylene film layer, the plane parts of the top and bottom surfaces of the micro device and the plane parts of the profiled surface are all directly sprayed, and the edges of the top and bottom surfaces of the micro device and the non-planar parts of the profiled surface are sprayed at an angle of 30-45 degrees based on the respective plane parts, the sandblasting pressure is 0.5-4Pa, and the sandblasting time is 5-30 seconds; the micro device is placed in a second reagent for dehydration; and the micro device is dried. The present invention can effectively improve the efficiency and accuracy of removing the mask layer and the parylene film layer on the profiled surface of the micro device, while greatly reducing the potential risk of damage to the device.

Description

Technical Field

[0001] The invention relates to the technical field of coating removal, and in particular to a method for coating and removing parylene from a micro device with an internal channel and a special-shaped surface. Background Art

[0002] The unique structure and stable properties of the Parylene film give it excellent protective performance, and it is usually used to protect electronic products, semiconductor devices and other products. Usually, due to the subsequent processing requirements of the device, some areas do not need the Parylene film, and only some areas need to be coated with the Parylene film.

[0003] In view of this situation, since it is impossible to coat a certain area with the parylene film layer alone, the prior art usually achieves the purpose of partially coating the parylene film layer by coating first and then removing the film layer.

[0004] There are two common methods for forming partially coated parylene layers. The first method is to directly coat all areas with parylene layers, and then remove the layers from areas where parylene layers are not needed. However, due to the high chemical stability and high adhesion of parylene, direct removal is extremely difficult.

[0005] The second method is to first mask the area where the parylene film is not needed with a mask layer, coat the parylene film on all areas, and then remove the parylene film and the mask layer together. Although this method increases the process cost to a certain extent, because the parylene film is not directly deposited on the surface, it greatly reduces the difficulty of removing the parylene film.

[0006] However, even if the second method is adopted, there are still technical difficulties in coating and removing the parylene film layer on the surface of current semiconductor devices.

[0007] First, semiconductor devices are small in size. With the development of the semiconductor industry, the integration of devices has been continuously improved. Today, centimeter-level and millimeter-level components are already quite common. Miniaturization means that the chemicals or physical methods used in the film removal process need to be more refined and controllable, and film removal must be very precise, which greatly increases the difficulty of film removal.

[0008] Second, the structure of semiconductor devices is complex. There are some channel structures inside the semiconductor devices, and there are often some special-shaped structures such as solder pillars and bumps on their surfaces. The particularity of these structures must be taken into account when removing the film. However, traditional film removal methods cannot accurately and effectively remove the film layer in a specific area. During the removal process, the film layer that does not need to be removed or even the structures themselves may be damaged. At the same time, the structure of the semiconductor device will also affect the setting of the mask layer in the coating method. The matching between the film removal method and the coating method is also an issue that needs to be considered.

[0009] Therefore, how to coat and remove the parylene film on micro devices with internal channels and irregular surfaces is a problem that researchers and technicians are eager to solve.

[0010] Traditional processes often fail to achieve ideal results when removing films from irregular surfaces. The film removal accuracy is poor, and there is still film residue after film removal, which may even damage the device. Sandblasting is a traditional process widely used in surface treatment. It uses compressed air or other power sources to spray abrasives at high speed onto the surface of the workpiece to achieve the desired surface effect. However, there is no research in the prior art on removing parylene film layers on micro devices with internal channels and irregular surfaces by sandblasting.

[0011] It should be noted that this part of the present invention only provides background technology related to the present invention and does not necessarily constitute prior art or known technology. Summary of the invention

[0012] In view of this, the purpose of the present invention is to provide a method for coating and removing parylene on a micro device with an internal channel and a profiled surface, so as to at least solve the problem that the prior art cannot coat and remove parylene film layers on micro devices with internal channels and profiled surfaces. The present invention can effectively improve the efficiency and accuracy of removing the mask layer and the parylene film layer on the profiled surface of the micro device by reasonably selecting the coating and removal methods of the parylene film layer, while greatly reducing the potential risk of damage to the device.

[0013] The present invention provides a method for coating and removing parylene from a micro device having an internal channel and a profiled surface, comprising the following steps:

[0014] S101, forming a mask layer on the top surface of the micro device, the bottom surface of the micro device, and the special-shaped surface, wherein the peeling strength of the mask layer is less than 1N / mm, and the tensile strength is less than 30Mpa;

[0015] S102, coating the inner and outer surfaces of the micro device with a parylene film layer by a vapor deposition method;

[0016] S103, fixing the micro device in a through hole of the fixture, wherein a special-shaped recess matching the special-shaped surface is provided on the inner wall of the through hole, and the special-shaped recess is used to wrap the special-shaped surface along the circumferential direction;

[0017] S104, using sodium bicarbonate or dry ice to sandblast the micro device to remove the mask layer and the parylene film layer, the sandblasting direction of the flat parts of the top and bottom surfaces of the micro device and the flat parts of the profiled surface are all straight, and the sandblasting direction of the edges of the top and bottom surfaces of the micro device and the non-flat parts of the profiled surface is 30-45 degrees based on the respective flat parts, the sandblasting pressure is 0.5-4 Pa, and the sandblasting time is 5-30 seconds;

[0018] S105, placing the sandblasted micro-device into a second reagent for dehydration;

[0019] S106, drying the dehydrated micro-device.

[0020] In some embodiments, the mask layer has a peel strength of 0.3-0.5 N / mm and a tensile strength of 10-20 MPa.

[0021] In some embodiments, in S104, the micro-device is sandblasted with sodium bicarbonate, and the mesh size of the sodium bicarbonate is 80-300 meshes.

[0022] In some embodiments, in S104, when sodium bicarbonate is used, the sandblasting pressure is 0.5-3Pa.

[0023] In some embodiments, in S104, when sodium bicarbonate is used, the sandblasting time is 10-30 seconds.

[0024] In some embodiments, before performing S105 , the step further includes placing the sandblasted micro-device into a first reagent for immersion until the sodium bicarbonate remaining on the micro-device is completely dissolved.

[0025] In some embodiments, the first reagent is deionized water, and the conductivity of the deionized water is less than 20 μs / cm.

[0026] In some embodiments, the soaking time is 5-60 minutes.

[0027] In some embodiments, the conductivity of the deionized water is less than 10 μS / cm.

[0028] In some embodiments, in S104, dry ice is used to sandblast the micro device, and the dry ice is fine-grained dry ice with a diameter between 0.1-3 mm.

[0029] In some embodiments, in S104, when dry ice is used, the blasting pressure is 1-4 Pa.

[0030] In some embodiments, in S104, when dry ice is used, the sandblasting time is 5-20 seconds.

[0031] In some embodiments, in S105, the second reagent is one of isopropanol and ethanol.

[0032] In some embodiments, in S105, the dehydration time is 3-30 minutes.

[0033] In some embodiments, in S106, the drying condition is vacuum drying at 40-60°C for 30-60 minutes.

[0034] In some embodiments, in S103 , the thickness of the through hole is not less than the thickness of the micro device by 0.2-0.4 mm.

[0035] In some embodiments, the dimensions of the microdevice are 4.5×4.2×1-5×4.6×1.5 mm.

[0036] The beneficial effects that can be achieved by the present invention are:

[0037] The present invention uses a physical sandblasting method to remove the mask layer and the parylene film layer on the profiled surface. The difficulty of using the physical sandblasting method to remove the film on the surface of the micro-device with a profiled surface is that the profiled parts of most semiconductor micro-devices are made of precious metal materials, which have low hardness and poor impact resistance due to their very small size, so it is necessary to select a suitable sandblasting material. The present invention uses sodium bicarbonate or dry ice to sandblast and remove the film on the micro-device, wherein the Mohs hardness of sodium bicarbonate and dry ice is approximately between 2-3. The hardness of the above materials is low, and sandblasting and removing the film can avoid damage to the fragile semiconductor device, but the use of the above materials with low hardness for sandblasting and removing the film increases the risk of not being able to effectively remove the mask layer. The applicant of the present invention has studied for the first time the relationship between the mechanical properties and process conditions of using sodium bicarbonate or dry ice as a sandblasting material to peel off the mask layer and the parylene film layer on the profiled surface, and selected a mask layer with a specific peeling strength and tensile strength, and matched a specific sandblasting angle to effectively peel off the mask layer without leaving any residue on the film layer while ensuring that the micro-device is not damaged.

[0038] Furthermore, the applicant of the present invention creatively discovered that the peeling strength and tensile strength of the mask layer can be controlled within an appropriate range at the same time, and the mask layer can be peeled off better by coordinating with a suitable sandblasting angle. One possible guess is that since the profiled surface requires multi-angle sandblasting to complete the peeling of the non-planar portion of the mask layer, the sprayed sand material not only has shear force but also tensile force on the mask layer and the parylene film layer. By adjusting the appropriate angle to match the peeling strength and tensile strength of the mask layer, the film can be removed efficiently. At the same time, the deposition thickness of the parylene film layer is much lower than the thickness of the mask layer (for example, the thickness of parylene is 0.01-0.05mm, and the thickness of the mask layer is 0.1-1mm). Therefore, when the mask layer is removed by sandblasting, ensuring that the mechanical properties of the mask layer meet certain standards can ensure the integrity of the peeling of the parylene film layer.

[0039] Furthermore, after the present invention uses sodium bicarbonate to sandblast and remove the film of the microdevice, the sodium bicarbonate remaining on the microdevice is removed by deionized water to avoid affecting the performance of the microdevice. Sodium bicarbonate has good solubility in water. The sodium bicarbonate sandblasting material remaining on the surface of the microdevice can be dissolved very well by soaking in deionized water. The efficiency is high and it can be removed in batches, and the removal is uniform without dead ends. The present invention also places the sandblasted microdevice in reagents such as isopropanol for dehydration, which can effectively remove residual sand particles, dust and impurities such as old coatings or rust that have been removed on the surface of the microdevice, ensuring that the surface of the workpiece is clean and providing good surface conditions for subsequent painting, welding or other processing processes.

[0040] Furthermore, the present invention uses dry ice to sandblast and remove the film of the micro device. The low temperature characteristics of dry ice can change the properties of the mask layer to a certain extent, increase the brittleness of the mask layer, and promote the removal efficiency of the mask layer. At the same time, dry ice also has a sublimation property. This property makes it unnecessary to soak the micro device in deionized water after sandblasting and removing the film with dry ice, which can further simplify the process, improve the process efficiency, and reduce the process cost.

[0041] Furthermore, the present invention adopts a specific sandblasting process and a special jig design, which can remove the mask layer and the parylene film layer of a micro device with an internal channel and a special-shaped surface in an entirety, without the need to separately process the special-shaped surface or the surface of the micro device, thereby greatly improving the production efficiency. At the same time, the present invention adopts a specific sandblasting process and a special jig design, which can prevent the sandblasting material from entering the internal channel of the micro device during the sandblasting process, avoid damaging the parylene film layer of the internal channel, and ensure that the internal coating still has good protective performance after sandblasting.

[0042] Furthermore, the present invention adopts a specific mask layer in combination with a specific sandblasting process, and utilizes the synergistic effects of the mechanical properties of the mask layer, the hardness of the sand material, the sandblasting pressure, the sandblasting time and the sandblasting angle, to creatively solve the problem of how to deposit a parylene film layer on the surface of a microdevice with an internal channel and a special-shaped surface and remove a specific surface mask layer and a parylene film layer, which is a problem that is currently urgently needed to be solved in the field. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0044] Figure 1 A schematic diagram of a TEC in an embodiment of the present invention is shown;

[0045] Figure 2 A cross-sectional schematic diagram is shown when the TEC is disposed on a fixture and the solder pillars are independently divided in an embodiment of the present invention;

[0046] Figure 3 A cross-sectional schematic diagram is shown when the TEC is disposed on a fixture and the solder pillars are not independently distinguished in an embodiment of the present invention;

[0047] Figure 4 The microscopic image of the TEC surface after the film is removed obtained in Example 1 of the present invention is shown;

[0048] Figure 5 The microscopic image of the TEC surface after film removal obtained in Example 3 of the present invention is shown;

[0049] Figure 6 The microscopic image of the TEC surface after the film is removed obtained in Example 4 of the present invention is shown;

[0050] Figure 7 A partial enlarged view of the solder column of the TEC surface microscope image after film removal obtained in Example 4 of the present invention is shown;

[0051] Figure 8 The TEC surface micrograph after film removal obtained in Comparative Example 3 of the present invention is shown;

[0052] Fig. 9 A partial enlarged view of the solder column of the TEC surface microscope image after film removal obtained in Comparative Example 3 of the present invention is shown.

[0053] Description of reference numerals:

[0054] 11. Semiconductor; 12. Top cover plate; 13. Bottom cover plate; 14. Solder column; 20. Fixture; 21. Special-shaped depression. DETAILED DESCRIPTION

[0055] The term "comprising" in the specification and claims of the present invention and the drawings is synonymous with "including", "containing" or "characterized by", and is inclusive or open-ended, and does not exclude additional undescribed elements or method steps. "Comprising" is a technical term used in the claim language, meaning that the elements are present, but other elements may also be added and still form a structure or method within the scope of the claim.

[0056] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance. The term "about" in the present invention means to include a small change (up to + / -10%) from the stated value.

[0057] It should be noted that the micro-devices with internal channels and irregular surfaces mentioned in the present invention are not particularly limited. TEC (thermoelectric cooler) will be used as an example to illustrate the technical solution of the present invention, but the following description does not constitute a limitation on the scope of protection of the present invention. The micro-devices mentioned in the present invention are preferably TEC but are not limited to this. They can also be other micro-devices with internal channels and irregular structures such as IC (integrated circuit), sensor, optoelectronic device, etc. More specifically, the surfaces of various array-packaged semiconductor devices have irregular structures such as solder joints, bumps, solder columns, pins, and pins, and also have array channels inside.

[0058] The parylene coating and film removal method provided by the present invention has no special restrictions on micro devices with internal channels and special-shaped surfaces. As long as the micro devices have internal array channels and special-shaped structures such as solder joints, bumps, solder columns, pins, and tube pins, the method of the present invention can be used to partially coat the parylene film layer.

[0059] like Figure 1 As shown, TEC includes an internal semiconductor 11, a conductive metal, a top cover plate 12, a bottom cover plate 13 and two solder pillars 14 spaced apart at one end of the TEC. The bottom cover plate 13 of the TEC is longer than the top cover plate 12. The two solder pillars 14 are spaced apart at the portion of the bottom cover plate 13 that exceeds the top cover plate 12. A gold layer is plated on the surface of the solder pillars 14. The height of the two solder pillars 14 is lower than the top cover plate 12.

[0060] Based on the above structure, the finished TEC needs to be welded with wires to connect to the power supply, so the welding column is the area where the parylene film layer is not needed. The top and bottom cover plates are the heat transfer areas, and in order to reduce thermal resistance, they are also the areas where the parylene film layer is not needed. How to achieve the purpose of partially coating the parylene film layer on the TEC is at least one of the technical problems solved by the embodiments of the present invention.

[0061] Based on the above structure, the irregular surface of TEC specifically refers to the irregular surface formed on the surface of the solder column. How to effectively remove the mask layer and the parylene film layer on the surface of the cover plate and the surface of the solder column without damaging the surface of the solder column, the gold layer on the edge of the solder column, the surface of the cover plate and the edge of the cover plate is at least one of the technical problems solved by the embodiments of the present invention.

[0062] Based on the above structure, the internal channel of TEC specifically refers to the gap between the semiconductors between the upper and lower cover plates of TEC. How to remove the mask layer and the parylene film layer on the surface of the cover plate and the surface of the solder column without damaging the thickness of the parylene film layer in the gap is at least one of the technical problems solved by the embodiments of the present invention.

[0063] The present invention provides a method for coating and removing parylene from a micro device having an internal channel and a profiled surface, comprising the following steps:

[0064] S101, forming a mask layer on the top surface of the micro device, the bottom surface of the micro device, and the special-shaped surface, wherein the peeling strength of the mask layer is less than 1N / mm, and the tensile strength is less than 30Mpa;

[0065] S102, coating the inner and outer surfaces of the micro device with a parylene film layer by a vapor deposition method;

[0066] S103, fixing the micro device in a through hole of the fixture, wherein a special-shaped recess matching the special-shaped surface is provided on the inner wall of the through hole, and the special-shaped recess is used to wrap the special-shaped surface along the circumferential direction;

[0067] S104, using sodium bicarbonate or dry ice to sandblast the micro device to remove the mask layer and the parylene film layer, the sandblasting direction of the flat parts of the top and bottom surfaces of the micro device and the flat parts of the profiled surface are all straight, and the sandblasting direction of the edges of the top and bottom surfaces of the micro device and the non-flat parts of the profiled surface is 30-45 degrees based on the respective flat parts, the sandblasting pressure is 0.5-4 Pa, and the sandblasting time is 5-30 seconds;

[0068] S105, placing the sandblasted micro-device into a second reagent for dehydration;

[0069] S106, drying the dehydrated micro-device.

[0070] In some embodiments, the peel strength of the mask layer is 0.3-0.5 N / mm, and can be 0.3 N / mm, 0.4 N / mm, 0.5 N / mm, and any value therebetween. Preferably, the peel strength is 0.4 N / mm.

[0071] The peeling strength of the mask layer is an important indicator for evaluating the bonding strength between the mask layer and the micro-device. The present invention reasonably sets the peeling strength of the mask layer, which ensures that the mask layer can remain stable when the parylene film is coated, and enables the mask layer to be effectively removed in the subsequent sandblasting removal step. The peeling strength of the mask layer and the sandblasting removal process need to be optimized in a coordinated manner. The present invention can enhance the physical response of the mask layer during the sandblasting process by simultaneously optimizing the peeling strength of the mask layer and the specific parameters of the sandblasting process to achieve the best film removal effect.

[0072] In some embodiments, the tensile strength is 10-20 MPa, and can be 10 MPa, 12 MPa, 14 MPa, 16 MPa, 18 MPa, 20 MPa and any value therebetween. Preferably, the tensile strength is 12 MPa.

[0073] The tensile strength of the mask layer is an important indicator to measure its ability to resist deformation during the processing. The present invention reasonably sets the tensile strength of the mask layer, which ensures that the mask layer can remain stable when the parylene film layer is coated, and enables the mask layer to be effectively removed in the subsequent sandblasting removal step. Appropriate tensile strength can prevent the mask layer from being too difficult to remove, affecting the removal efficiency, and can also prevent the mask layer from being damaged prematurely during the sandblasting process. By simultaneously optimizing the tensile strength of the mask layer and the specific parameters of the sandblasting process, the present invention can enhance the physical response of the mask layer during the sandblasting process to achieve the best film removal effect.

[0074] It should be noted that the applicant of the present invention creatively discovered that the peeling strength and tensile strength of the mask layer can be controlled within an appropriate range at the same time and in combination with a suitable sandblasting angle to better complete the peeling of the mask layer. One possible guess is that since the special-shaped surface requires multi-angle sandblasting technology to complete the peeling of the non-planar part of the mask layer, the sprayed sand not only exerts a shear force but also a tensile force on the mask layer and the parylene film layer. By adjusting the appropriate angle to match the peeling strength and tensile strength of the mask layer, the adhesive film can be efficiently removed.

[0075] In some embodiments, the mask layer of the present invention is prepared from an acrylate adhesive. Preferably, the mask layer is composed of the following components in percentage by mass: 15-30% isobornyl acrylate, 45-65% polyurethane modified methacrylic resin, 5-15% hexanediol diacrylate, 5-10% acrylic acid, and 0-1% adhesion promoter. The peel strength of the mask layer prepared using the above components is <1N / mm, and the tensile strength is <30Mpa.

[0076] It should be noted that in S101, the present invention has no particular limitation on the specific method for forming the mask layer, and any technique well known to those skilled in the art may be used.

[0077] It should be noted that in S102, the present invention has no particular restrictions on the deposition conditions of the vapor deposition method and the parylene material, and the technology well known to those skilled in the art or commercially available products may be used.

[0078] It should be noted that, in S102 , the interior of the micro device at least includes an internal channel, and the exterior of the micro device at least includes a micro device top surface, a micro device bottom surface, and a special-shaped surface.

[0079] In some embodiments, in S104, the microdevice is sandblasted with sodium bicarbonate, and the mesh number of the sodium bicarbonate is 80-300 mesh. Preferably, the mesh number of the sodium bicarbonate is 200 mesh, but it is not limited thereto, and can be 80 mesh, 120 mesh, 160 mesh, 240 mesh, 300 mesh, and any value therebetween. The present invention uses sodium bicarbonate with a suitable particle size to remove the film layer on the surface faster, reducing processing time and cost. The present invention uses sodium bicarbonate with moderate hardness and suitable particle size to avoid scratches or excessive wear on the workpiece surface. The sodium bicarbonate used in the present invention is a non-metallic environmentally friendly sandblasting material that can reduce the impact on the environment. The uniform particle size and shape of the sodium bicarbonate of the present invention can ensure the uniformity of the workpiece surface treatment during the sandblasting process.

[0080] In some embodiments, in S104, when sodium bicarbonate is used, the sandblasting pressure is 0.5-3Pa. Preferably, the sandblasting pressure is 1.5Pa, but is not limited thereto, and can be 0.5Pa, 1Pa, 2Pa, 2.5Pa, 3Pa, and any value therebetween. The present invention selects a suitable sandblasting pressure according to the characteristics and hardness of the micro-device material. The present invention reasonably sets the sandblasting pressure to completely remove the film layer while avoiding damage to the device. In addition, in the above case, the sandblasting pressure is controlled to improve processing efficiency.

[0081] In some embodiments, in S104, when sodium bicarbonate is used, the sandblasting time is 10-30 seconds. Preferably, the sandblasting time is 20 seconds, but it is not limited thereto, and can be 10 seconds, 15 seconds, 25 seconds, 30 seconds, and any value therebetween. Generally speaking, the sandblasting time is inversely proportional to the sandblasting pressure, that is, the longer the sandblasting time, the sandblasting pressure can be appropriately reduced; the shorter the sandblasting time, the sandblasting pressure needs to be increased to ensure the sandblasting effect. Comprehensive selection of the above-mentioned sandblasting pressure and sandblasting time can simultaneously ensure removal effect and production efficiency.

[0082] In some embodiments, before performing S105, the micro device after sandblasting is placed in a first reagent for soaking until the sodium bicarbonate remaining on the micro device is completely dissolved. The sodium bicarbonate remaining on the micro device is removed by soaking to avoid affecting the performance of the micro device.

[0083] In some embodiments, the first reagent is deionized water, and the conductivity of the deionized water is less than 20μs / cm. Preferably, the conductivity of the deionized water is less than 10μs / cm, but is not limited thereto, and can be 1μs / cm, 5μs / cm, 15μs / cm, and any value therebetween. For deionized water, the lower the conductivity, the lower the ion content in the water. Deionized water with low conductivity can reduce the impact of impurities on the performance of microdevices. During the cleaning process, deionized water with low conductivity generates less static electricity during cleaning, which helps to reduce the adsorption of particles, thereby improving the cleaning effect. Deionized water with low conductivity reduces the ions in the water, preventing these ions from forming deposits or causing corrosion on the surface of the device, and can extend the service life of the microdevice. Using deionized water with low conductivity can reduce residues and improve the reliability of microdevices.

[0084] It should be noted that the appearance standard of micro devices does not allow sodium bicarbonate to remain on the surface, and it must be cleaned. Sodium bicarbonate has good solubility in water and can dissolve the sodium bicarbonate blasting material remaining on the surface of the product very well. The use of deionized water has high removal efficiency and can be removed in batches, and the removal is uniform without dead ends. The choice of low-conductivity deionized water is related to the purpose of micro devices. Micro devices are mostly used in refrigeration equipment such as chip electronics, and it is necessary to reduce residues and improve the reliability of micro devices.

[0085] Optionally, the first reagent may also be distilled water.

[0086] In some embodiments, the soaking time is 5-60 minutes. Preferably, the soaking time is 30 minutes, but it is not limited thereto, and can be 5 minutes, 10 minutes, 20 minutes, 40 minutes, 50 minutes, 60 minutes and any value therebetween. The present invention sets a reasonable soaking time to ensure both the removal effect and production efficiency of sodium bicarbonate. The soaking lower limit time is at least 5 minutes to completely dissolve the sodium bicarbonate blasting material remaining on the surface. The parylene layer itself has a very good waterproof effect, but too long a soaking time will affect the production efficiency, so the soaking upper limit time is 60 minutes.

[0087] In some embodiments, in S104, dry ice is used to sandblast the microdevice, and the dry ice is fine-grained dry ice with a diameter between 0.1-3 mm. Preferably, the diameter of the dry ice is 1.5 mm, but is not limited thereto, and can be 0.1 mm, 0.5 mm, 1 mm, 2 mm, 2.5 mm, 3 mm, and any value therebetween. The present invention uses dry ice with a suitable particle size to ensure the removal effect and remove the surface film layer faster, reducing processing time and cost.

[0088] In some embodiments, in S104, when dry ice is used, the sandblasting pressure is 1-4Pa. Preferably, the sandblasting pressure is 2Pa, but is not limited thereto, and may be 1Pa, 1.5Pa, 2.5Pa, 3Pa, 3.5Pa, 4Pa, and any value therebetween. The present invention selects a suitable sandblasting pressure according to the characteristics and hardness of the micro-device material. The present invention reasonably sets the sandblasting pressure to completely remove the film layer while avoiding damage to the device. In addition, in the above case, the sandblasting pressure is controlled to improve processing efficiency.

[0089] It should be noted that the upper limit of the sandblasting pressure when using dry ice can be slightly higher than the upper limit of the sandblasting pressure when using sodium bicarbonate. The Mohs hardness of dry ice is 2, and the Mohs hardness of sodium bicarbonate is 2.5-3.0. The hardness of dry ice is relatively small, and the damage to the product surface is also small, so a sandblasting pressure with a higher upper limit can be used.

[0090] In some embodiments, in S104, when dry ice is used, the sandblasting time is 5-20 seconds. Preferably, the sandblasting time is 10 seconds, but is not limited thereto, and can be 5 seconds, 8 seconds, 15 seconds, 20 seconds, and any value therebetween. The present invention sets a reasonable sandblasting time to ensure both removal effect and production efficiency.

[0091] It should be noted that the upper limit of the sandblasting time when using dry ice can be slightly lower than the upper limit of the sandblasting time when using sodium bicarbonate. This is mainly because the upper limit of the sandblasting pressure when using dry ice is higher than that of sodium bicarbonate. At the same time, dry ice is better at controlling the sandblasting angle than sodium bicarbonate. When dry ice is used for sandblasting, the area of ​​action is larger than that of sodium bicarbonate.

[0092] The sandblasting pressure affects the impact ability of the sand particles, and thus affects whether the sandblasting material can effectively remove the surface film layer. In the prior art, there has been no research on the relationship between the sandblasting pressure and the removal of the mask layer and the parylene film layer on the surface of micro devices with internal channels and special-shaped surfaces. The present invention reasonably sets the sandblasting pressure to completely remove the film layer while avoiding damage to the device. In addition, the present invention also controls the sandblasting pressure in the above situation to improve the processing efficiency.

[0093] In some embodiments, in S104, sodium bicarbonate or dry ice is used to sandblast the microdevice, and the sandblasting direction of the planar portion of the top and bottom surfaces of the microdevice and the planar portion of the profiled surface is straight, and the sandblasting direction of the edge of the top and bottom surfaces of the microdevice and the non-planar portion of the profiled surface is 30-45 degrees based on the respective planar portion. Preferably, the sandblasting direction of the edge and the non-planar portion is 40 degrees, but it is not limited thereto, and can be 30 degrees, 35 degrees, 45 degrees, and any value therebetween.

[0094] It should be noted that the angle control of sodium bicarbonate blasting is relatively easy, and the nozzle is relatively small and can be accurately positioned. Dry ice blasting has a faster removal speed, but it is more difficult to achieve accuracy and has a higher return rate.

[0095] It should be noted that the sandblasting angle of the edge is based on the respective plane part, and the plane part is the 0-degree angle reference plane. Therefore, it can be understood that when the sandblasting angle is too large, most of the sandblasting particles will be blocked by the mold, resulting in the inability to completely remove the film layer on the edge. When the sandblasting angle is too small, it is equivalent to direct sandblasting on the edge. For the edge, the sandblasting force is too large and it is easy to damage the edge.

[0096] The sandblasting angle affects the contact area and incident angle between the sand particles and the workpiece surface, and further affects whether the mask layer and parylene film layer of the irregular surface that are blocked by other surfaces can be completely removed. At the same time, different angles will also affect the impact force and cutting force. The irregular surfaces in semiconductor equipment are mostly relatively fragile parts such as welding columns. There is a lack of research on the difference between the sandblasting angle and the mechanical properties of the irregular surface parts in the prior art, and therefore there is also a lack of research on suitable processing conditions. The sandblasting direction of the planar parts of the top and bottom surfaces of the micro device of the present invention and the planar parts of the irregular surface are all direct spraying, which can effectively remove the thicker mask layer and parylene film layer of the planar part. The sandblasting direction of the edges of the top and bottom surfaces of the micro device and the non-planar parts of the irregular surface is sprayed at an angle of 30-45 degrees based on the respective planar parts. On the basis of ensuring that there is no film layer residue on the edge, the edge can also be guaranteed to be smooth and scratch-free.

[0097] In some embodiments, in S105, the second reagent is one of isopropanol and ethanol. Easily volatile solutions such as alcohol or isopropanol can be selected for dehydration, in order to shorten the drying time. Preferably, the second reagent is isopropanol, because the cost of ethanol is higher than that of isopropanol. It is not recommended to adopt other alcohol compounds, because other alcohol compounds are mostly toxic, and safety measures need to be taken if they must be used.

[0098] In some embodiments, in S105, the dehydration time is 3-30 minutes. Preferably, the dehydration time is 10 minutes, but is not limited thereto, and can be 3 minutes, 5 minutes, 8 minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes and any value therebetween. The present invention sets a reasonable dehydration time to ensure both removal effect and production efficiency. The longer the dehydration time, the less water remains, and the easier it is to dry, but too long a dehydration time can affect production efficiency.

[0099] In some embodiments, in S106, the drying condition is vacuum drying at 40-60°C for 30-60 minutes. Preferably, the drying temperature is 50°C, but is not limited thereto, and can be 40°C, 45°C, 55°C, 60°C, and any value therebetween.

[0100] Preferably, the drying time is 50 minutes, but is not limited thereto, and can be 30 minutes, 35 minutes, 45 minutes, 55 minutes, 60 minutes, and any value therebetween.

[0101] In semiconductor manufacturing, the wafer must be completely dried after cleaning to avoid the formation of water spots. At the same time, drying can ensure that the surface of the micro-device after cleaning is dry and free of residue, thereby improving the quality of the final micro-device.

[0102] In some embodiments, in S103, the thickness of the through hole is not less than 0.2-0.4 mm of the thickness of the micro device. Preferably, the thickness of the through hole is not less than 0.3 mm of the thickness of the micro device, but is not limited thereto, and can be 0.2 mm, 0.25 mm, 0.35 mm, 0.4 mm, and any value therebetween.

[0103] It should be noted that, taking TEC as an example, the thickness of the micro device refers to the height between the top surface of the bottom cover plate and the bottom surface of the top cover plate of the TEC. The present invention makes the thickness of the through hole not less than the thickness of the micro device, so that the micro device can be completely surrounded by the through hole, so that the sandblasting is concentrated on the surface that needs to be de-filmed, thereby improving the de-filming efficiency.

[0104] It should be noted that the thickness of the jig should be at least enough to cover more than half of the top and bottom TEC covers to prevent the internal channels of the TEC from being exposed. The thickness of the jig should not be too thick, otherwise the edges of the cover and solder column will not be reached during sandblasting.

[0105] In some embodiments, the size of the micro device is 4.5×4.2×1-5×4.6×1.5 mm. The present invention uses a specific sandblasting process to remove the film from the special-shaped surface of the millimeter-level micro device, which can effectively improve the efficiency and accuracy of film removal, while greatly reducing the potential risk of damage to the device. As a typical example, the length×width×height×solder column height of the TEC is 4.8×4.4×1.13×0.9 mm respectively.

[0106] It should be noted that the fixture 20 is provided with a plurality of through holes, and the inner wall of the through holes is provided with a shaped recess 21 matching the shaped surface, and the shaped recess 21 is used to wrap the shaped surface along the circumferential direction. Figure 2 As shown, one end of the irregular recess 21 is integrally formed with the inner wall of the through hole, and the other end is tightly abutted with the cover plate. The irregular recess 21 has two receiving holes, and the two receiving holes are completely matched with the two solder pillars. When the through hole has the irregular recess 21, the two solder pillars can be completely fitted with the irregular recess 21 for clamping, and the gap between the solder pillar and the cover plate is completely filled, so that the two solder pillars can be independently distinguished. Preferably, a through hole jig 20 without the irregular recess 21 can be formed first, and after the TEC is placed in the through hole, the space leaking from the through hole is filled with material to form the irregular recess 21.

[0107] The advantage of this setting is that it prevents the sandblasting material from entering the gap between the cover plate and the two welding columns, which can concentrate the sandblasting stress and improve the film removal efficiency. At the same time, it also prevents the sandblasting material from entering the gap between the semiconductors between the upper and lower cover plates of the TEC, avoiding damage to the Parylene film layer on the internal channel, ensuring that the internal coating still has good protective performance after sandblasting film removal.

[0108] It should be noted that the material of the fixture of the present invention is silicone material, which is a soft material that can withstand high and low temperatures, has high chemical stability, has certain elasticity, small compression deformation, is wear-resistant, can be reused, and has customizable color and hardness. If a hard material is used as a fixture, the film layer on the surface of the product is easily damaged during the clamping process.

[0109] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0110] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0111] The following will take TEC (thermoelectric cooler) as an example to illustrate the technical solution of the present invention, but the following description does not constitute a limitation on the protection scope of the present invention. The test method for the peel strength of the mask layer refers to ATM-D1002, and the test method for the tensile strength refers to ASTM-D638.

[0112] Example 1

[0113] S101. A mask layer is formed on the surface of the TEC top cover plate, the TEC bottom cover plate, and the TEC solder column. The mask layer is composed of the following components in percentage by mass: 20% isobornyl acrylate, 60% polyurethane modified methacrylate resin, 12% hexanediol diacrylate, 7% acrylic acid, and 1% adhesion promoter. The peel strength of the mask layer is 0.4 N / mm, and the tensile strength is 12 MPa.

[0114] S102, coating the inner and outer surfaces of the TEC with a parylene film layer by a vapor deposition method.

[0115] S103. The fixture is designed to be rectangular in shape. The TEC is fixed in the through hole of the fixture. The inner wall of the through hole is provided with a special-shaped depression matching the solder column. The solder column is independently distinguished. The thickness of the through hole is 0.3 mm greater than that of the TEC.

[0116] S104, use sodium bicarbonate to sandblast the TEC, the mesh size of the sodium bicarbonate is 200 mesh, the sandblasting pressure is 1.5pa, the sandblasting time is 20 seconds, the flat part of the top layer and bottom cover plate of the TEC, and the flat part of the welding column are directly sprayed, and the edges of the top layer and bottom cover plate of the TEC and the edges of the welding column are obliquely sprayed at a 40-degree angle.

[0117] S105, soaking the sandblasted TEC in deionized water for 30 minutes, then taking out the TEC and dehydrating it in isopropanol liquid for 10 minutes.

[0118] S106, drying the dehydrated TEC at 50° C. in vacuum for 50 minutes.

[0119] Example 2

[0120] S101. A mask layer is formed on the surface of the TEC top cover plate, the TEC bottom cover plate, and the TEC solder column. The mask layer is composed of the following components in percentage by mass: 20% isobornyl acrylate, 60% polyurethane modified methacrylate resin, 12% hexanediol diacrylate, 7% acrylic acid, and 1% adhesion promoter. The peel strength of the mask layer is 0.4 N / mm, and the tensile strength is 12 MPa.

[0121] S102, coating the inner and outer surfaces of the TEC with a parylene film layer by a vapor deposition method.

[0122] S103. The fixture is designed to be rectangular in shape. The TEC is fixed in the through hole of the fixture. The inner wall of the through hole is provided with a special-shaped depression matching the solder column. The solder column is independently distinguished. The thickness of the through hole is 0.3 mm greater than that of the TEC.

[0123] S104, use sodium bicarbonate to sandblast the TEC, the mesh size of the sodium bicarbonate is 200 mesh, the sandblasting pressure is 2.5pa, the sandblasting time is 20 seconds, the flat part of the top layer and bottom cover plate of the TEC, and the flat part of the welding column are directly sprayed, and the edges of the top layer and bottom cover plate of the TEC and the edges of the welding column are obliquely sprayed at a 40-degree angle.

[0124] S105, soaking the sandblasted TEC in deionized water for 30 minutes, then taking out the TEC and dehydrating it in isopropanol liquid for 10 minutes.

[0125] S106, drying the dehydrated TEC at 50° C. in vacuum for 50 minutes.

[0126] Example 3

[0127] S101. A mask layer is formed on the surface of the TEC top cover plate, the TEC bottom cover plate, and the TEC solder column. The mask layer is composed of the following components in percentage by mass: 20% isobornyl acrylate, 60% polyurethane modified methacrylate resin, 12% hexanediol diacrylate, 7% acrylic acid, and 1% adhesion promoter. The peel strength of the mask layer is 0.4 N / mm, and the tensile strength is 12 MPa.

[0128] S102, coating the inner and outer surfaces of the TEC with a parylene film layer by a vapor deposition method.

[0129] S103. The fixture is designed to be rectangular in shape. The TEC is fixed in the through hole of the fixture. The inner wall of the through hole is provided with a special-shaped depression matching the solder column. The solder column is independently distinguished. The thickness of the through hole is 0.3 mm greater than that of the TEC.

[0130] S104, use sodium bicarbonate to sandblast the TEC, the mesh size of the sodium bicarbonate is 200 mesh, the sandblasting pressure is 1.5pa, the sandblasting time is 10 seconds, the flat part of the top layer and bottom cover plate of the TEC, and the flat part of the welding column are directly sprayed, and the edges of the top layer and bottom cover plate of the TEC and the edges of the welding column are sprayed at a 40-degree angle.

[0131] S105, soaking the sandblasted TEC in deionized water for 30 minutes, then taking out the TEC and dehydrating it in isopropanol liquid for 10 minutes.

[0132] S106, drying the dehydrated TEC at 50° C. in vacuum for 50 minutes.

[0133] Example 4

[0134] S101. A mask layer is formed on the surface of the TEC top cover plate, the TEC bottom cover plate, and the TEC solder column. The mask layer is composed of the following components in percentage by mass: 20% isobornyl acrylate, 60% polyurethane modified methacrylate resin, 12% hexanediol diacrylate, 7% acrylic acid, and 1% adhesion promoter. The peel strength of the mask layer is 0.4 N / mm, and the tensile strength is 12 MPa.

[0135] S102, coating the inner and outer surfaces of the TEC with a parylene film layer by a vapor deposition method.

[0136] S103. The fixture is designed to be rectangular in shape. The TEC is fixed in the through hole of the fixture. The inner wall of the through hole is provided with a special-shaped depression matching the solder column. The solder column is independently distinguished. The thickness of the through hole is 0.3 mm greater than that of the TEC.

[0137] S104. Use sodium bicarbonate to sandblast the TEC. The mesh size of the sodium bicarbonate is 200 mesh, the sandblasting pressure is 1.5pa, and the sandblasting time is 20 seconds. Direct spraying is used for the flat parts of the top and bottom cover plates of the TEC, and the flat parts of the welding columns. The edges of the top and bottom cover plates of the TEC, and the edges of the welding columns are sprayed at a 35-degree angle.

[0138] S105, soaking the sandblasted TEC in deionized water for 30 minutes, then taking out the TEC and dehydrating it in isopropanol liquid for 10 minutes.

[0139] S106, drying the dehydrated TEC at 50° C. in vacuum for 50 minutes.

[0140] Example 5

[0141] S101. A mask layer is formed on the surface of the TEC top cover plate, the TEC bottom cover plate, and the TEC solder column. The mask layer is composed of the following components in percentage by mass: 20% isobornyl acrylate, 60% polyurethane modified methacrylate resin, 12% hexanediol diacrylate, 7% acrylic acid, and 1% adhesion promoter. The peel strength of the mask layer is 0.4 N / mm, and the tensile strength is 12 MPa.

[0142] S102, coating the inner and outer surfaces of the TEC with a parylene film layer by a vapor deposition method.

[0143] S103. The fixture is designed to be rectangular in shape. The TEC is fixed in the through hole of the fixture. The inner wall of the through hole is provided with a special-shaped depression matching the solder column. The solder column is independently distinguished. The thickness of the through hole is 0.3 mm greater than that of the TEC.

[0144] S104, use dry ice to sandblast the TEC. The dry ice is fine-grained dry ice with a diameter of 1.5mm, the sandblasting pressure is 2pa, and the sandblasting time is 10 seconds. Direct spraying is used for the flat parts of the top and bottom cover plates of the TEC, and the flat parts of the welding columns. The edges of the top and bottom cover plates of the TEC, and the edges of the welding columns are sprayed at a 40-degree angle.

[0145] S105, placing the sandblasted TEC in isopropyl alcohol liquid for dehydration for 10 minutes.

[0146] S106, drying the dehydrated TEC at 50° C. in vacuum for 50 minutes.

[0147] Example 6

[0148] S101. A mask layer is formed on the surface of the TEC top cover plate, the TEC bottom cover plate, and the TEC solder column. The mask layer is composed of the following components in percentage by mass: 20% isobornyl acrylate, 60% polyurethane modified methacrylate resin, 12% hexanediol diacrylate, 7% acrylic acid, and 1% adhesion promoter. The peel strength of the mask layer is 0.4 N / mm, and the tensile strength is 12 MPa.

[0149] S102, coating the inner and outer surfaces of the TEC with a parylene film layer by a vapor deposition method.

[0150] S103. The fixture is designed to be rectangular in shape. The TEC is fixed in the through hole of the fixture. The inner wall of the through hole is provided with a special-shaped depression matching the solder column. The solder column is independently distinguished. The thickness of the through hole is 0.3 mm greater than that of the TEC.

[0151] S104, use dry ice to sandblast the TEC. The dry ice is fine-grained dry ice with a diameter of 1.5mm, the sandblasting pressure is 3.5pa, and the sandblasting time is 10 seconds. Direct spraying is used for the flat parts of the top and bottom cover plates of the TEC, and the flat parts of the welding columns. The edges of the top and bottom cover plates of the TEC, and the edges of the welding columns are sprayed at a 40-degree angle.

[0152] S105, placing the sandblasted TEC in isopropyl alcohol liquid for dehydration for 10 minutes.

[0153] S106, drying the dehydrated TEC at 50° C. in vacuum for 50 minutes.

[0154] Example 7

[0155] S101. A mask layer is formed on the surface of the TEC top cover plate, the TEC bottom cover plate, and the TEC solder column. The mask layer is composed of the following components in percentage by mass: 20% isobornyl acrylate, 60% polyurethane modified methacrylate resin, 12% hexanediol diacrylate, 7% acrylic acid, and 1% adhesion promoter. The peel strength of the mask layer is 0.4 N / mm, and the tensile strength is 12 MPa.

[0156] S102, coating the inner and outer surfaces of the TEC with a parylene film layer by a vapor deposition method.

[0157] S103. The fixture is designed to be rectangular in shape. The TEC is fixed in the through hole of the fixture. The inner wall of the through hole is provided with a special-shaped depression matching the solder column. The solder column is independently distinguished. The thickness of the through hole is 0.3 mm greater than that of the TEC.

[0158] S104, use dry ice to sandblast the TEC. The dry ice is fine-grained dry ice with a diameter of 1.5mm, the sandblasting pressure is 2pa, and the sandblasting time is 5 seconds. Direct spraying is used for the flat parts of the top and bottom cover plates of the TEC, and the flat parts of the welding columns. The edges of the top and bottom cover plates of the TEC, and the edges of the welding columns are sprayed at a 40-degree angle.

[0159] S105, placing the sandblasted TEC in isopropyl alcohol liquid for dehydration for 10 minutes.

[0160] S106, drying the dehydrated TEC at 50° C. in vacuum for 50 minutes.

[0161] Example 8

[0162] S101. A mask layer is formed on the surface of the TEC top cover plate, the TEC bottom cover plate, and the TEC solder column. The mask layer is composed of the following components in percentage by mass: 20% isobornyl acrylate, 60% polyurethane modified methacrylate resin, 12% hexanediol diacrylate, 7% acrylic acid, and 1% adhesion promoter. The peel strength of the mask layer is 0.4 N / mm, and the tensile strength is 12 MPa.

[0163] S102, coating the inner and outer surfaces of the TEC with a parylene film layer by a vapor deposition method.

[0164] S103. The fixture is designed to be rectangular in shape. The TEC is fixed in the through hole of the fixture. The inner wall of the through hole is provided with a special-shaped depression matching the solder column. The solder column is independently distinguished. The thickness of the through hole is 0.3 mm greater than that of the TEC.

[0165] S104, use dry ice to sandblast the TEC. The dry ice is fine-grained dry ice with a diameter of 1.5 mm, the sandblasting pressure is 2 Pa, and the sandblasting time is 10 seconds. Direct spraying is used for the flat parts of the top and bottom cover plates of the TEC, and the flat parts of the welding columns. The edges of the top and bottom cover plates of the TEC, and the edges of the welding columns are sprayed at a 35-degree angle.

[0166] S105, placing the sandblasted TEC in isopropyl alcohol liquid for dehydration for 10 minutes.

[0167] S106, drying the dehydrated TEC at 50° C. in vacuum for 50 minutes.

[0168] Comparative Example 1

[0169] The method of Example 1 is used, except that the sandblasting pressure is 4.5 Pa.

[0170] Comparative Example 2

[0171] The method of Example 1 was followed, except that the sandblasting pressure was 0.3 Pa.

[0172] Comparative Example 3

[0173] The method of Example 1 is referred to, except that the sandblasting time is 40 seconds, and the sandblasting direction of the edges of the TEC top layer, bottom cover plate, and solder column is 50 degrees based on the respective plane parts.

[0174] Comparative Example 4

[0175] The method of Example 1 was followed, except that the sandblasting time was 3 seconds.

[0176] Comparative Example 5

[0177] The method of Example 1 is referred to, except that the sandblasting direction of the edges of the TEC top layer, bottom cover plate, and solder column is sprayed at an angle of 20 degrees based on the respective plane portions.

[0178] Comparative Example 6

[0179] The method of Example 1 is referred to, except that the mask layer is composed of the following components in percentage by mass: 40% isobornyl acrylate, 35% polyurethane modified methacrylate resin, 5% hexanediol diacrylate, and 20% acrylic acid, and the peel strength of the mask layer is 1.5 N / mm, and the tensile strength is 40 MPa.

[0180] Comparative Example 7

[0181] The method of Example 5 was followed, except that the sandblasting pressure was 4.5 Pa.

[0182] Comparative Example 8

[0183] The method of Example 5 was followed, except that the sandblasting pressure was 0.3 Pa.

[0184] Comparative Example 9

[0185] The method of Example 5 is referred to, except that the sandblasting time is 40 seconds, and the sandblasting direction of the edges of the TEC top layer, bottom cover plate, and solder column edge is 50 degrees based on the respective plane parts.

[0186] Comparative Example 10

[0187] The method of Example 5 was followed, except that the sandblasting time was 3 seconds.

[0188] Comparative Example 11

[0189] The method of Example 5 is referred to, except that the sandblasting direction of the edges of the TEC top layer, bottom cover plate, and solder column is sprayed at an angle of 20 degrees based on the respective plane portions.

[0190] Comparative Example 12

[0191] The method of Example 5 is referred to, except that the mask layer is composed of the following components in percentage by mass: 40% isobornyl acrylate, 35% polyurethane modified methacrylate resin, 5% hexanediol diacrylate, and 20% acrylic acid, and the peel strength of the mask layer is 1.5 N / mm, and the tensile strength is 40 MPa.

[0192] Test Case

[0193] The TECs after film removal obtained in the above embodiments and comparative examples were subjected to appearance inspection, and the results of the appearance inspection are shown in Table 1. The appearance inspection method is to fully inspect the TEC cover surface and cover edge under a 20x microscope to see if there is any coating residue, scratches, whether there is any film residue on the gold layer on the solder column surface and solder column edge, and whether there is any discoloration and scratches on the gold layer on the solder column surface and solder column edge.

[0194] It should be noted that the film residues of the TEC structure in Table 1 are divided into none, a small amount and a large amount. None means that there is no film residue at this position or only film residues that are difficult to observe; a small amount means that there is a small area of ​​observable film residues at this position, but it will not affect the subsequent use of TEC and no further treatment is required; a large amount means that there is a large area of ​​observable film residues at this position, which has affected the subsequent use of TEC and needs further treatment to remove the residual film or be eliminated as a defective product.

[0195] In Table 1, the scratches and discoloration of the TEC structure are divided into none, slight and severe. None means that there are no scratches or discoloration at that location or only scratches or discoloration that are difficult to observe; slight means that the number of scratches at that location is small and the area of ​​discoloration is small, but it does not affect the subsequent use of TEC; severe means that the number of scratches at that location is large and the area of ​​discoloration is large, which has affected the subsequent use of TEC and needs to be eliminated as a defective product.

[0196] Table 1

[0197]

[0198] like Figure 4 As shown, Figure 4 This is a microscopic image of the TEC surface after film removal obtained by the sandblasting process in Example 1. Under a 20x microscope, it is observed that there is no film residue on the surface of the TEC cover plate, no scratches, no film residue on the edge of the cover plate, no film residue on the surface of the solder column, no different color, no scratches, and no film residue on the edge of the solder column, no different color, and no scratches.

[0199] like Figure 5 As shown, Figure 5 This is a microscopic image of the TEC surface after film removal obtained by the sandblasting process of Example 3. Under a 20x microscope, the TEC cover plate surface has no film layer residue, no scratches, a small amount of film layer residue on the edge of the cover plate, no scratches, no film layer residue on the surface of the solder column, no discoloration, no scratches, and no film layer residue on the edge of the solder column, no discoloration, no scratches. It can be seen from the figure that a small amount of film layer residue is on the edge of the cover plate in the upper right corner of the picture.

[0200] like Figure 6 As shown, Figure 6 This is a microscopic image of the TEC surface after film removal obtained by the sandblasting process of Example 4. Under a 20x microscope, the TEC cover plate surface has no film layer residue, no scratches, no film layer residue at the edge of the cover plate, slight scratches, no film layer residue on the solder column surface, no discoloration, no scratches, no film layer residue at the edge of the solder column, slight discoloration, and no scratches. It can be seen from the figure that the edge of the cover plate has slight scratches.

[0201] like Figure 7 As shown, Figure 7 This is a partial magnified image of the solder column of the TEC surface microscope image after film removal obtained by the sandblasting process of Example 4. It can be seen that there is no film layer remaining on the surface of the solder column, no discoloration, and no scratches. There is no film layer remaining on the edge of the solder column, with slight discoloration and no scratches. It can be seen from the figure that the solder column above the picture has a slight discoloration.

[0202] like Figure 8 As shown, Figure 8 This is a microscopic image of the TEC surface after film removal obtained by the sandblasting process of comparative example 3. Under a 20x microscope, the TEC cover plate surface has no film layer residue and no scratches, the edge of the cover plate has a large amount of film layer residue and severe scratches, the solder column surface has no film layer residue and no discoloration, and severe scratches, and the edge of the solder column has a large amount of film layer residue and no discoloration, and severe scratches. It can be seen from the figure that there are a large amount of film layer residues on the edges of the cover plates above and below the picture, and the lower cover plate edge is particularly serious. At the same time, there are multiple dense scratches on the edge of the cover plate on the left side of the picture, and there are severe scratches.

[0203] like Fig. 9 As shown, Fig. 9 This is a partial enlarged view of the solder column of the TEC surface microscope image after film removal obtained by the sandblasting process of Comparative Example 3. It can be seen that there is no film layer remaining on the surface of the solder column, no discoloration, and severe scratches. There is a large amount of film layer remaining on the edge of the solder column, no discoloration, and severe scratches. It can be seen from the figure that the entire solder column has severe scratches, and a large amount of film layer remains on the edge of the solder column.

[0204] According to Examples 1 and 2, when the sandblasting pressure is greater than the preferred sandblasting pressure, slight damage may be caused to the TEC cover and the solder column. By adopting the preferred sandblasting pressure of the present invention, the efficiency and accuracy of film layer removal can be more effectively improved and damage to the device can be avoided.

[0205] According to Example 1 and Example 3, when the sandblasting time is less than the preferred sandblasting time, a small amount of film layer may still exist on the edge of the TEC cover plate. By adopting the preferred sandblasting time of the present invention, the efficiency and accuracy of film layer removal can be more effectively improved and damage to the device can be avoided.

[0206] According to Example 1 and Example 4, when the sandblasting angle is smaller than the preferred sandblasting angle, the force of the sandblasting becomes greater, which may cause slight damage to the edges of the TEC cover and the solder column. By adopting the preferred sandblasting angle of the present invention, the efficiency and accuracy of film layer removal can be more effectively improved and damage to the device can be avoided.

[0207] The properties of the sodium bicarbonate and dry ice of the present invention are similar, and the present invention makes a separate adaptive adjustment to the sandblasting process according to the difference between sodium bicarbonate and dry ice. Therefore, when the changing trends of Examples 5-8 are the same as those of Examples 1-4, the same conclusions can be obtained in Examples 5-8.

[0208] From the above results, it can be seen that according to Examples 1, 2-4, 5, and 6-8, by adopting the preferred sandblasting process of the present invention and using the sandblasting pressure, sandblasting time, and sandblasting angle under the preferred values, the efficiency and accuracy of film layer removal can be more effectively improved and damage to the device can be avoided.

[0209] According to Example 1 and Comparative Example 1, when the sandblasting pressure exceeds the threshold value specified in the present invention, serious damage may be caused to the TEC cover plate and the solder column. The sandblasting pressure of the technical solution of the present invention can effectively improve the efficiency and accuracy of film removal, while greatly reducing the potential risk of damage to the device.

[0210] According to Example 1 and Comparative Example 2, when the sandblasting pressure is lower than the threshold value specified in the present invention, a large amount of film may still remain on the TEC cover plate and the solder column. The sandblasting pressure of the technical solution of the present invention can effectively improve the efficiency and accuracy of film removal, while greatly reducing the potential risk of damage to the device.

[0211] According to Example 1 and Comparative Example 3, when the sandblasting angle exceeds the threshold value specified in the present invention, a considerable portion of the sandblasting particles are blocked by the mold, resulting in a large amount of film layer remaining on the edge of the TEC cover plate and the solder column. However, because the sandblasting time exceeds the threshold value specified in the present invention, a small number of unblocked sandblasting particles continue to sandblast, which will cause serious damage to relatively more easily damaged parts such as the entire solder column or the edge of the substrate, and may eventually lead to a situation where a large amount of film layer remains and the device is seriously damaged. The sandblasting time and sandblasting angle of the technical solution of the present invention can effectively improve the efficiency and accuracy of film layer removal, while greatly reducing the potential risk of damage to the device.

[0212] According to Example 1 and Comparative Example 4, when the sandblasting time is lower than the threshold value specified in the present invention, a large amount of film may still remain on the TEC cover plate and the solder column. The sandblasting pressure of the technical solution of the present invention can effectively improve the efficiency and accuracy of film removal, while greatly reducing the potential risk of damage to the device.

[0213] According to Example 1 and Comparative Example 5, when the sandblasting angle is lower than the threshold value specified in the present invention, it is closer to direct sandblasting on the edge. For the edge, excessive sandblasting force may cause serious damage to the TEC cover plate and solder column. The sandblasting angle of the technical solution of the present invention can effectively improve the efficiency and accuracy of film removal, while greatly reducing the potential risk of damage to the device.

[0214] According to Example 1 and Comparative Example 6, when the peel strength and tensile strength of the mask layer exceed the threshold value specified in the present invention, the sandblasting cannot completely remove the mask layer, and a large amount of film layer may still remain on the TEC cover plate and the solder column. The peel strength and tensile strength of the mask layer using the technical solution of the present invention can effectively improve the efficiency and accuracy of film layer removal, while greatly reducing the potential risk of damage to the device.

[0215] The properties of the sodium bicarbonate and dry ice of the present invention are similar, and the present invention makes a separate adaptive adjustment to the sandblasting process according to the difference between sodium bicarbonate and dry ice. Therefore, when the variation trend of comparative examples 7-12 is the same as that of comparative examples 1-6, the same conclusion can be obtained for comparative examples 7-12.

[0216] From the above results, it can be seen that, compared with the comparative example, the embodiment of the present invention can effectively improve the efficiency and accuracy of film removal, while greatly reducing the potential risk of damage to the device. Whether sodium bicarbonate or dry ice is used, within the sandblasting process technology scheme specified in the present invention, the film layer can be effectively removed, while the damage to the TEC is reduced and the yield is high.

[0217] Furthermore, in order to specifically verify the technical effect of the fixture design of the present invention, the performance of the TEC after film removal obtained according to Examples 1 and 5 of the present invention was tested. At this time, the through hole had a special-shaped depression, and the two solder pillars could be completely fitted with the special-shaped depression for clamping, and the gap between the solder pillar and the cover plate was completely filled, so that the two solder pillars could be independently distinguished. Specifically, Figure 2 shown.

[0218] The performance of the TEC after film removal obtained according to Example 1 and Example 5 of the present invention is tested. The difference is that there is no irregular depression on the through hole at this time, the gap between the solder column and the cover plate is not filled, and the two solder columns are not independently distinguished. Figure 3 shown.

[0219] The performance test results of TEC after film removal with different fixture designs are shown in Table 2. The performance test method is to detect the internal coating thickness and protective performance. The internal coating thickness refers to the thickness of the parylene film layer on the gap between the semiconductors between the upper and lower cover plates of the TEC, and the protective performance also refers to the protective performance of the parylene film layer on the gap between the semiconductors.

[0220] Table 2

[0221]

[0222] From the above results, it can be seen that the fixture design using the technical solution of the present invention can prevent the sandblasting material from entering the gap between the semiconductors between the upper and lower cover plates of the TEC, effectively avoiding the situation where the coating thickness inside the TEC is damaged during the film removal process, and ensuring that only the film layer in the area where the parylene coating is not required is removed after the film removal, while the parylene film layer inside the TEC can still maintain its protective performance.

[0223] The embodiments of the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for coating and removing parylene from a micro device having an internal channel and a profiled surface, characterized in that: The following steps are involved: S101, forming a mask layer on the top surface of the micro device, the bottom surface of the micro device, and the profiled surface, wherein the peel strength of the mask layer is less than 1 N / mm, and the tensile strength is less than 30 MPa; S102, coating the inner and outer surfaces of the micro-device with a parylene film layer by a vapor deposition method; S103, fixing the micro device in a through hole of a fixture, wherein an irregularly shaped recess matching the irregularly shaped surface is provided on an inner wall of the through hole, and the irregularly shaped recess is used to wrap the irregularly shaped surface along a circumferential direction; S104, using sodium bicarbonate or dry ice to sandblast the micro device to remove the mask layer and the parylene film layer, the sandblasting direction of the planar parts of the top and bottom surfaces of the micro device and the planar parts of the profiled surface are both straight, and the sandblasting direction of the edges of the top and bottom surfaces of the micro device and the non-planar parts of the profiled surface is 30-45 degrees based on the respective planar parts, the sandblasting pressure is 0.5-4 Pa, and the sandblasting time is 5-30 seconds; S105, placing the sandblasted micro-device into a second reagent for dehydration; S106, drying the dehydrated micro-device.

2. The method for coating and removing parylene from a micro device having an internal channel and a profiled surface according to claim 1, characterized in that: The mask layer has a peel strength of 0.3-0.5 N / mm and a tensile strength of 10-20 MPa.

3. The method for coating and removing parylene from a micro device having an internal channel and a profiled surface according to claim 1, characterized in that: In S104, the micro-device is sandblasted with sodium bicarbonate, and the mesh size of the sodium bicarbonate is 80-300 meshes.

4. The method for coating and removing parylene from a micro device having an internal channel and a profiled surface according to claim 3, characterized in that: In S104, the blasting pressure is 0.5-3Pa; and / or, In S104, the sandblasting time is 10-30 seconds.

5. The method for coating and removing parylene from a micro device having an internal channel and a profiled surface according to claim 3, characterized in that: Before performing S105, the method further includes placing the micro device after sandblasting into a first reagent for soaking until the sodium bicarbonate remaining on the micro device is completely dissolved.

6. The method for coating and removing parylene from a micro device having an internal channel and a profiled surface according to claim 5, characterized in that: The first reagent is deionized water, and the conductivity of the deionized water is less than 20 μs / cm; and / or, The soaking time is 5-60 minutes.

7. The method for coating and removing parylene from a micro device having an internal channel and a profiled surface according to claim 6, characterized in that: The conductivity of deionized water is less than 10μs / cm.

8. The method for coating and removing parylene from a micro device having an internal channel and a profiled surface according to claim 1, characterized in that: In S104, the micro device is sandblasted with dry ice, where the dry ice is fine-grained dry ice with a diameter between 0.1 and 3 mm.

9. The method for coating and removing parylene from a micro device having an internal channel and a profiled surface according to claim 8, characterized in that: In S104, the blasting pressure is 1-4Pa; and / or, In S104, the sandblasting time is 5-20 seconds.

10. The method for coating and removing parylene from a micro device having an internal channel and a profiled surface according to claim 1, characterized in that: In S105, the second reagent is one of isopropanol and ethanol; and / or, In S105, the dehydration time is 3-30 minutes.

11. The method for coating and removing parylene from a micro device having an internal channel and a profiled surface according to claim 1, characterized in that: In S106, the drying condition is vacuum drying at 40-60°C for 30-60 minutes.

12. The method for coating and removing parylene from a micro device having an internal channel and a profiled surface according to claim 1, characterized in that: In S103, the thickness of the through hole is not less than the thickness of the micro device by 0.2-0.4 mm.

13. The method for coating and removing parylene from a micro device having an internal channel and a profiled surface according to claim 1, characterized in that: The dimensions of the micro device are 4.5×4.2×1-5×4.6×1.5 mm.

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