A hard mask device for deep trench machining electrodes in MEMS
By using hard mask devices in MEMS manufacturing, the problems of device damage and solvent residue caused by metal etching and stripping processes have been solved, thereby improving product yield and reliability while reducing production costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHEJIANG XINDONG TECH CO LTD
- Filing Date
- 2025-07-24
- Publication Date
- 2026-07-03
AI Technical Summary
In MEMS manufacturing, existing metal etching and stripping processes cause damage to device structures, solvent residues, and contamination, affecting product yield and reliability.
Hard mask fixtures, including wafer devices and hard masks, are used to form specific structures on the hard mask through micro-nano processing techniques such as photolithography and etching. Combined with bonding machines and tape fixation, metal patterning deposition is achieved, avoiding direct manipulation of the wafer. HF solution is used to remove the oxide layer, and acetone solution is used to clean the residue.
It improves product yield and reliability, reduces the impact of solvent residue on device structure, lowers production costs, and enables the reuse of hard masks.
Smart Images
Figure CN224450803U_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of MEMS manufacturing technology, and more specifically, to a hard mask device for deep trench machining electrodes in MEMS. Background Technology
[0002] In the manufacturing process of microelectromechanical systems (MEMS), microstructured devices often require the fabrication of metal pads to form ohmic contacts. This is a key step in connecting the device to external circuits. Currently, metal etching and stripping are the two most commonly used processing methods in the industry. In the metal etching process, photoresist plays a crucial transitional role.
[0003] First, the photoresist is patterned using photolithography to form a specific pattern. Then, the patterned photoresist is used as a mask to perform reactive etching on the metal layer, thereby transferring the pattern on the photoresist onto the metal layer and achieving the purpose of patterning.
[0004] The subsequent photoresist removal process presents numerous challenges. Photoresist removal typically involves the use of solutions or plasma, and this process is often accompanied by complex changes in the process environment.
[0005] Metal stripping also relies on photoresist as a transition material. First, photoresist is patterned using photolithography. Then, metal is evaporated onto the patterned photoresist. Finally, the unwanted metal parts are removed using a stripping process, thus achieving the transfer of the patterned metal.
[0006] However, some solutions are used in this process, and these solutions may remain on the device surface. For wafers with multilayer bonding, the device structure itself is relatively fragile and the surface condition is complex. Solvent residues can erode or contaminate the device structure, affecting the electrical and mechanical properties of the device.
[0007] Moreover, during the stripping process, the adhesion between the metal and the photoresist, as well as the stripping force, may cause mechanical damage to the microstructure of the device, leading to defects and reducing the yield and reliability of the product. Utility Model Content
[0008] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a hard mask device for MEMS deep trench machining electrodes that improves the yield and reliability of products.
[0009] To achieve the above objectives, the present invention provides the following technical solution:
[0010] A hard mask device for deep trench machining electrodes in MEMS includes a wafer device and a hard mask.
[0011] The hard mask is placed on the wafer device and fixedly connected to the wafer device.
[0012] The hard mask has through-hole components, several rows of holes and slots.
[0013] The through-hole assembly has two sets, with the hole positions and openings both located within the two sets of through-hole assemblies.
[0014] There are two slots, which are symmetrically distributed with the center of the hard mask as the reference point.
[0015] Both slots are located within the holes.
[0016] The through-hole assembly includes several rows of first blind holes, several rows of second blind holes, and several rows of third blind holes.
[0017] The second blind hole is located between the first blind hole and the second blind hole.
[0018] The number of third blind holes is greater than the number of second blind holes, which in turn is greater than the number of first blind holes.
[0019] The present invention is further configured such that the hard mask and the wafer device are fixed together by a bonding machine and adhesive tape.
[0020] The present invention is further configured such that the slot is square.
[0021] By adopting the above technical solution, the beneficial effects of this utility model are as follows:
[0022] By using hard masks to achieve patterned metal deposition, damage caused by direct wafer processing is effectively avoided, the impact of solvent residue on device structure is reduced, and product yield and reliability are improved. At the same time, hard masks can be reused, reducing production costs. Attached Figure Description
[0023] Figure 1 This is a cross-sectional view of an embodiment of the present utility model;
[0024] Figure 2 This is a top view of the hard mask of this utility model.
[0025] 1. Wafer device, 2. Hard mask, 3. Through-hole assembly, 4. Hole, 5. Slot, 301 first blind hole, 302 second blind hole, 303 third blind hole. Detailed Implementation
[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0027] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0028] like Figures 1 to 2 As shown, the hard mask fixture for MEMS deep trench machining electrodes includes a wafer device 1 and a hard mask 2. The hard mask 2 and the wafer device 1 are fixed together by a bonding machine and adhesive tape. The bonding machine provides high-precision alignment, ensuring the precise positional relationship between the hard mask 2 and the wafer device 1, achieving the first fixation of the hard mask 2 and the wafer device 1. The adhesive tape plays an auxiliary fixing role, ensuring that the hard mask 2 will not shift during subsequent processes, thus achieving the second fixation of the hard mask 2 and the wafer device 1.
[0029] The hard mask 2 has through-hole components 3, several rows of holes 4 and slots 5. There are two sets of through-hole components 3. The holes 4 and slots 5 are placed in the two sets of through holes. There are two slots 5. The two slots 5 are symmetrically distributed with the center of the hard mask 2 as the reference point. Both slots 5 are placed in the holes 4. The slots 5 are square. This symmetrical and square slot design helps to achieve more accurate positioning and more uniform metal deposition in the process.
[0030] The through-hole assembly 3 includes several rows of first blind holes 301, several rows of second blind holes 302, and several rows of third blind holes 303. The second blind holes 302 are located between the first blind holes 301 and the third blind holes 303. The number of openings in the third blind holes 303 is greater than the number of openings in the second blind holes 302, and the number of openings in the second blind holes 302 is greater than the number of openings in the first blind holes 301. This arrangement design of different numbers of blind holes can achieve precise control of metal vapor deposition according to actual process requirements and meet the patterning requirements of metal electrodes at different positions.
[0031] 1. Hard mask 2 processing: According to the product layout, metal or silicon wafers are processed using micro-nano processing techniques such as photolithography and etching to drill holes at the locations on the wafer device 1 where metal electrodes are to be fabricated, forming a hard mask 2 with the specific structure described above. During the processing, structures such as oxide layers may be formed on the wafer surface.
[0032] 2. Hard Mask 2 Post-processing: The completed hard mask is processed by using HF solution to remove the oxide layer used in the fabrication process. HF solution can react chemically with the oxide layer and dissolve it. After that, the hard mask 2 is cleaned, for example by rinsing with deionized water, to ensure that metal vapor can pass through the orifice normally and to avoid oxide layer residue or impurities clogging the orifice and affecting the metal deposition effect.
[0033] III. Fixing the hard mask 2 to the wafer device 1: The fabricated hard mask 2 is aligned and fixed onto the wafer device 1 using a bonding alignment machine and a fixture. The bonding alignment machine can precisely adjust the position of the hard mask 1 so that it accurately corresponds to the target position on the wafer device 1. The fixture then firmly fixes the hard mask 2 onto the wafer device 1. Subsequently, high-temperature resistant tape is used to fix it again to cope with the high-temperature environment during the subsequent metal evaporation process and to prevent the hard mask 2 from loosening or falling off.
[0034] IV. Metal Deposition: The wafer device 1 with the hard mask 2 attached is placed together in the metal evaporation stage for metal evaporation. During the evaporation process, the metal vapor will pass through the through-hole components 3, holes 4 and other structures on the hard mask 2 and be deposited on the surface of the wafer device 1 according to the predetermined pattern to complete the metal patterning.
[0035] V. Post-processing: After metal deposition is completed, remove the hard mask 2 and store it for future use. Remove any remaining traces on the edge of wafer device 1 by wiping with acetone solution. Acetone solution can dissolve residual metal or impurities, restoring the surface of wafer device 1 to cleanliness.
[0036] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any ordinary changes and substitutions made by those skilled in the art within the scope of the technical solution of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A hard mask tooling for MEMS deep trench processing electrodes, characterized by, It includes wafer devices (1) and hard masks (2). The hard mask (2) is placed on the wafer device (1) and fixedly connected to the wafer device (1). The hard mask (2) has through-hole assembly (3), several rows of holes (4) and slots (5). The through-hole assembly (3) has two sets, and the hole position (4) and opening are both placed in the two sets of through-hole assemblies (3). There are two slots (5), and the two slots (5) are symmetrically distributed with the center of the hard mask (2) as the reference point. Both slots (5) are placed within the holes (4). The through-hole assembly (3) includes several rows of first blind holes (301), several rows of second blind holes (302) and several rows of third blind holes (303). The second blind hole (302) is located between the first blind hole (301) and the second blind hole (302). The number of openings in the third blind hole (303) is greater than the number of openings in the second blind hole (302) and the number of openings in the first blind hole (301).
2. The hard mask apparatus for MEMS deep trench processing electrodes of claim 1, wherein, The hard mask (2) and the wafer device (1) are fixed together by a bonding machine and adhesive tape.
3. The hard mask apparatus for MEMS deep trench processing electrodes of claim 1, wherein, The slot (5) is square.