A processing method for quartz devices and quartz devices.

Abstract

This invention provides a processing method for quartz devices and the quartz devices themselves. The processing method includes: Step 1, preparing a quartz wafer; Step 2, determining the area to be removed based on the desired quartz device, and using laser modification on the area to be removed on the quartz wafer; Step 3, preparing a metal film layer on both the upper and lower surfaces of the quartz wafer obtained in Step 2; Step 4, patterning the metal film layer to determine the quartz structure pattern, which is approximately consistent with the laser-modified pattern in Step 2, exposing the area to be removed; Step 5, preparing a second mask pattern on the patterned metal film layer surface to determine the electrode pattern; Step 6, removing the area to be removed using a chemical solution; Step 7, etching the metal film layer to transfer the electrode pattern on the second mask layer onto the metal film layer; Step 8, removing the second mask layer. This invention improves the processing accuracy and efficiency of quartz structures.

Description

Technical Field

[0001] This invention relates to the field of quartz devices, and in particular to a processing method for quartz devices and quartz devices themselves. Background Technology

[0002] Quartz devices are devices that use quartz crystal material and operate by utilizing the piezoelectric effect and inverse piezoelectric effect of quartz. They include many actuators and sensors such as quartz crystal oscillators, quartz tuning fork gyroscopes, and quartz vibrating beam accelerometers, and have been widely used in many fields.

[0003] Quartz devices typically require specific processing methods to fabricate quartz beam structures on a quartz substrate and prepare metal electrodes on the surface or sides to achieve beam resonance and signal output.

[0004] There are many methods for processing quartz structures, such as mechanical cutting, wet etching, dry etching, laser processing, and electrochemical etching. However, mechanical cutting has poor dimensional accuracy and cannot fabricate microstructures. Dry etching requires high-quality masks and produces poor etching morphology, thus limiting its widespread application in quartz devices. Electrochemical etching has limited technological maturity and is also rarely used in quartz devices. Wet etching technology is widely used in quartz devices due to its high processing accuracy and repeatability. This method uses a mixed solution of hydrofluoric acid and ammonium fluoride to etch the quartz material. However, this method is technically challenging. Due to the characteristics of quartz crystals, unwanted crystal structures or sharp defects can easily form on the sidewalls or etched surfaces of the structure, affecting the processing quality of the quartz structure.

[0005] In recent years, laser-induced chemical etching technology has been gradually studied, and it represents an improvement over wet etching technology for quartz. However, when applying this method to the processing of quartz devices, the main challenge is ensuring compatibility with the manufacturing process, as laser processing may damage the mask and electrodes on the surface of the structure. Summary of the Invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0007] Therefore, this invention provides a processing method for quartz devices and a quartz device itself. Based on a wet etching process, this invention introduces laser-induced chemical etching technology at specific processing times, making it compatible with quartz device processing. This avoids damage to the mask or electrodes on the structural surface, improving the processing accuracy and efficiency of quartz structures, thereby increasing the precision of quartz devices and reducing their cost.

[0008] The technical solution of the present invention is as follows:

[0009] According to one aspect, a method for processing quartz devices is provided, the method comprising:

[0010] Step 1: Prepare the quartz wafer;

[0011] Step 2: Determine the areas to be removed based on the desired quartz device, and use laser modification on the quartz wafer to remove these areas, including:

[0012] The laser scans the area to be removed in the x, y, and z directions to modify the area. There are two types of modification: one is to modify the entire area along the depth direction of the quartz wafer, and the other is to modify only to a preset depth for processing a thinner structure. When scanning any area to be removed, the part of the area that is a set thickness away from the surface of the quartz wafer is not scanned to ensure that the quartz structure on the surface of the area is not damaged.

[0013] Step 3: Prepare a metal film layer on both the upper and lower surfaces of the quartz wafer obtained in Step 2;

[0014] Step 4: Pattern the metal film layer and determine the quartz structure pattern. This pattern is roughly the same as the laser modification pattern in Step 2. Expose the area that needs to be removed.

[0015] Step 5: Prepare a second mask pattern on the surface of the patterned metal film to determine the electrode pattern;

[0016] Step 6: Use a chemical solution to remove the area to be removed. The chemical solution first corrodes the unmodified area in the area to be removed. After the modified area is exposed, it is then corroded. The corrosion rate of the modified area is greater than that of the unmodified area.

[0017] Step 7: Etch the metal film to transfer the electrode pattern on the second mask onto the metal film;

[0018] Step 8: Remove the second mask.

[0019] Furthermore, the quartz device includes a beam, a thinned structure, and a support structure.

[0020] Furthermore, the quartz wafer is made of quartz crystal material or fused quartz material.

[0021] Furthermore, the metal film layer is selected from any one of Cr / Au, Ti / Au, Cr / Au / Cr / Au.

[0022] Furthermore, the metal film patterning method in step 4 includes photolithography etching, stripping, or laser processing.

[0023] Furthermore, the second mask layer comprises photoresist or Cr / Au.

[0024] Furthermore, the chemical solution includes any one of hydrofluoric acid, a mixed solution of hydrofluoric acid and ammonium fluoride, ammonium bifluoride, and sodium hydroxide.

[0025] Furthermore, in step 2, only the boundaries of the area to be scanned may be scanned.

[0026] According to another aspect, a quartz device is provided, which is processed using the method described above.

[0027] In the quartz device processing, the above technical solution first introduces laser induction to partially modify the area to be modified, avoiding the damage to the metal film that may be caused by laser-induced chemical etching, thus avoiding undesirable defects in the quartz structure. At the same time, this solution is fully compatible with the traditional wet etching process and can process electrodes through photolithography, metal etching and other means, with higher processing precision.

[0028] In this invention, laser modification and traditional quartz processing flow do not interfere with each other, retaining the advantage of quartz processing in preparing complex and high-precision electrodes, while also achieving the optimization of fast laser-induced chemical etching and smooth thinning surface, and avoiding the mask and electrode damage problems that may be caused by laser modification; this invention can realize the processing of various complex quartz structures, including multi-layer unequal height structures, and can meet the processing needs of various quartz devices. Attached Figure Description

[0029] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0030] Figure 1 This is a typical cross-sectional diagram of a quartz structure;

[0031] 1 is a quartz wafer; 11 is a beam structure; 12 is a thinning structure; 13 is a support structure; 14 is an electrode.

[0032] Figure 2 This is a flowchart of the processing technology used in this invention.

[0033] 12 is the thinning structure; 14 is the metal mask; 3 is a schematic diagram of the scanning laser; 4 is the laser-modified area; 41 is the laser-modified area above the thinning structure; 5 is the second mask layer.

[0034] Figure 3 This is a schematic diagram of a cross-section of a quartz structure.

[0035] 1 is a quartz wafer; 11 is a beam structure; 12 is a thinning structure; 13 is a support structure; 14 is an electrode.

[0036] Figure 4 This is a schematic diagram of a cross-section of a quartz structure.

[0037] 1 is a quartz wafer; 11 is a beam structure; 12 is a thinning structure; 13 is a support structure; 14 is an electrode; 16 is a stepped structure.

[0038] Figure 5 This is a schematic diagram of a laser-modified region of a quartz structure.

[0039] 1 is a quartz wafer; 12 is a thinned structure; 15 is a peeled structure; 4 is a laser-modified region; 41 is a laser-modified region above the thinned structure. Detailed Implementation

[0040] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0042] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0043] like Figure 1 As shown, a typical quartz device consists of four parts: a resonant beam, a thinning structure, a support structure, and electrodes. The resonant beam is the core structure of the quartz device. The thinning structure differs from other structures in the height direction and requires additional etching processes for thinning. The support structure is mainly responsible for fixing the entire quartz structure, usually by bonding or welding it to an external package. The electrodes are mainly used for the collection and transmission of electrical signals.

[0044] The purpose of this invention is to fabricate resonant beams, thinning structures, and support structures.

[0045] like Figure 2 As shown, in one embodiment of the present invention, a processing method for quartz devices is provided, the processing method comprising:

[0046] Step 1: Prepare quartz wafer 1;

[0047] Step 2: Determine the area to be removed based on the desired quartz device, and use laser modification on the quartz wafer to remove the area, including:

[0048] The laser scans the area to be removed in the x, y, and z directions to modify the area. There are two types of modification: one is to modify the entire area along the depth direction of the quartz wafer, and the other is to modify only to a preset depth for processing a thinning structure. When scanning any area to be removed, the portion of that area that is a predetermined thickness away from the surface of the quartz wafer is not scanned to ensure that the quartz structure on the surface of that area is not damaged, thus obtaining the laser-modified area 4; where 12 is the thinning structure; 3 is a schematic diagram of the scanning laser; 41 is the laser-modified area above the thinning structure;

[0049] Step 3: A metal film layer 14 is prepared on both the upper and lower surfaces of the quartz wafer 1 obtained in step 2; it is used as an etching mask for the quartz structure and as an electrode;

[0050] Step 4: Pattern the metal film layer 14 to determine the quartz structure pattern. This pattern is roughly the same as the laser modification pattern in Step 2, exposing the area that needs to be removed.

[0051] Step 5: Prepare a second mask pattern on the surface of the patterned metal film layer 14 to determine the electrode pattern;

[0052] Step 6: Use a chemical solution to remove the area to be removed. The chemical solution first corrodes the unmodified area in the area to be removed. After the laser-modified area 4 is exposed, it is then corroded. The corrosion rate of the laser-modified area 4 is greater than that of the unmodified area.

[0053] Step 7: Etch the metal film 14 to transfer the electrode pattern on the second mask 5 onto the metal film 14;

[0054] Step 8: Remove the second mask layer 5.

[0055] In other words, the laser scans the quartz structure to be processed in the x, y, and z directions. By using a suitable laser and laser parameters, the quartz crystal at the scanned location can be modified, giving it a selectivity ratio of over 100:1 compared to the unmodified location during subsequent wet etching. This allows for rapid processing without damaging other structures. The modified area includes two types: one where the entire depth direction is modified, and the other where modification is limited to a certain depth, allowing for the processing of thinner structures. In this embodiment, the laser does not scan the area adjacent to the quartz wafer surface (i.e., in this embodiment, the area to be removed is partially modified, while the portion close to the quartz wafer surface is not scanned or modified), thus preserving the surface quartz structure and maintaining a smooth and flat surface on the quartz wafer.

[0056] In this embodiment of the invention, the quartz device includes a beam, a thinning structure, and a support structure. That is, a chemical solution is used to remove the laser-modified quartz structure, thereby processing the desired quartz structure, including the beam, thinning structure, and support structure. The unmodified areas of the surface are etched first at a slower rate, and then the modified areas are etched rapidly once exposed.

[0057] As can be seen, in the quartz device processing of this invention, laser-induced partial modification of the desired area is first introduced, avoiding the metal film damage that may be caused by laser-induced chemical etching, thus avoiding undesirable defects in the quartz structure. Simultaneously, this method is fully compatible with traditional wet etching processes, allowing electrodes to be processed using photolithography, metal etching, and other methods, resulting in higher processing precision. In this invention, laser modification and traditional quartz processing flows do not interfere with each other, retaining the advantage of quartz processing in fabricating complex, high-precision electrodes, while achieving the optimization of fast laser-induced chemical etching and smooth surface thinning, while avoiding the mask and electrode damage problems that may occur with laser modification. This invention can realize the processing of various complex quartz structures, including multi-layered structures with unequal heights, and can meet the processing needs of various quartz devices.

[0058] According to one embodiment of the present invention, the quartz wafer 1 can be a quartz crystal material or a fused quartz material, and the cut, crystal orientation and thickness of the quartz wafer 1 are not limited.

[0059] According to one embodiment of the present invention, the laser scanning area 4 in step 2 is related to the selection and parameters of the laser, and the distance between the laser scanning area 4 and the surface is not limited.

[0060] According to one embodiment of the present invention, the metal film layer 14 in step 3 includes, but is not limited to, Cr / Au, Ti / Au, Cr / Au / Cr / Au, etc., as long as it can meet the needs of the corrosion mask and the electrode.

[0061] According to one embodiment of the present invention, the patterning method of the metal film layer 14 in step 4 includes, but is not limited to, photolithography etching, stripping, laser processing, etc.

[0062] According to one embodiment of the present invention, the second mask 5 in step 5 includes, but is not limited to, photoresist, Cr / Au, etc.

[0063] According to one embodiment of the present invention, the chemical solution in step 6 includes, but is not limited to, hydrofluoric acid, a mixed solution of hydrofluoric acid and ammonium fluoride, ammonium bifluoride, sodium hydroxide, etc.

[0064] Furthermore, the embodiments of the present invention can also be applied to more complex quartz structures, especially thinning structures that can be more complex, such as those requiring thinning on both sides. Figure 3 As shown, the corresponding process requires laser scanning on the back of the quartz wafer. The thinning structure can also include various different depths, such as... Figure 4 As shown, 1 is a quartz wafer; 11 is a beam structure; 12 is a thinning structure; 13 is a support structure; 14 is an electrode; and 16 is a stepped structure, which only requires control of the laser scanning area.

[0065] Furthermore, in step 2 of the proposed solution, the same processing effect can be achieved by reducing the laser scanning area, such as... Figure 5 As shown, 1 represents a quartz wafer; 12 represents a thinned structure; 15 represents a peeled structure; 4 represents a laser-modified area; and 41 represents a laser-modified area above the thinned structure. Only the boundary of the area to be removed needs to be scanned. After the laser-modified area 4 is thoroughly etched, the structure to be removed 15 will automatically detach. This method can further improve processing efficiency.

[0066] According to another embodiment, a quartz device is provided, which is processed using the method described above.

[0067] The features described and / or illustrated above with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, and / or in combination with or in lieu of features in other embodiments.

[0068] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, whole, step, or component, but does not exclude the presence or addition of one or more other features, wholes, steps, components, or combinations thereof.

[0069] The methods described above in this invention can be implemented in hardware or in combination with software. This invention relates to computer-readable programs that, when executed by a logic component, enable the logic component to implement the aforementioned apparatus or constituent parts, or to implement the various methods or steps described above. This invention also relates to storage media for storing the above programs, such as hard disks, magnetic disks, optical disks, DVDs, flash memory, etc.

[0070] Many features and advantages of these embodiments are apparent from this detailed description, and therefore the appended claims are intended to cover all such features and advantages of these embodiments that fall within their true spirit and scope. Furthermore, since many modifications and alterations will readily occur to those skilled in the art, the embodiments of the invention are not intended to be limited to the precise structures and operations illustrated and described, but rather to encompass all suitable modifications and equivalents falling within their scope.

[0071] The parts of this invention not described in detail are techniques known to those skilled in the art.

Claims

1. A processing method for a quartz device, characterized by, The processing method comprises: Step 1, quartz wafer preparation; Step 2, determining the area to be removed according to the quartz device to be obtained, and modifying the area to be removed on the quartz wafer by laser, comprising: The laser scans the area to be removed in x, y and z directions to modify the area, and the modification types include two types, one is to modify the entire depth direction of the quartz wafer, and the other is to modify only to a preset depth for processing the thinning structure, wherein when scanning any area to be removed, the part of the area to be removed at a distance of a set thickness from the surface of the quartz wafer is not scanned to ensure that the quartz structure of the surface of the area is not damaged; Step 3, preparing a metal film layer on the upper and lower surfaces of the quartz wafer obtained in step 2; Step 4, patterning the metal film layer to determine the quartz structure pattern, which is substantially consistent with the laser modification pattern in step 2, so as to expose the area to be removed; Step 5, preparing a second mask pattern on the surface of the patterned metal film layer for determining the electrode pattern; Step 6, removing the area to be removed by using a chemical solution, wherein the chemical solution first corrodes the unmodified area in the area to be removed, and then corrodes the modified area when the modified area is exposed, and the corrosion rate of the modified area is greater than that of the unmodified area; Step 7, etching the metal film layer to transfer the electrode pattern on the second mask to the metal film layer; Step 8, removing the second mask.

2. A method for processing a quartz device according to claim 1, wherein The quartz device comprises a beam, a thinning structure and a support structure.

3. The method for processing a quartz device according to claim 1, wherein The quartz wafer is made of quartz crystal material or fused quartz material.

4. A method of processing a quartz device according to any one of claims 1 to 3, wherein The metal film layer is selected from any one of Cr / Au, Ti / Au, Cr / Au / Cr / Au.

5. A method for processing a quartz device according to any one of claims 1 to 4, characterized in that, The patterning method of the metal film layer in step 4 comprises photolithography etching, stripping or laser processing.

6. A method of processing a quartz device according to claim 5, wherein The second mask comprises photoresist or Cr / Au.

7. A method of processing a quartz device according to claim 5, wherein The chemical solution comprises any one of hydrofluoric acid, a mixed solution of hydrofluoric acid and ammonium fluoride, ammonium hydrogen fluoride, sodium hydroxide.

8. The method of processing a quartz device according to claim 1, wherein, In step 2, only the boundary of the area to be scanned can be scanned.

9. A quartz device, characterized by The quartz device is processed by the method of any one of claims 1-8.

Images