Processing method of special crystal direction sapphire double-polished wafer
By performing large-scale grinding and polishing and CNC edge processing on sapphire materials with special crystal orientations, and printing ink on the surface, the problem of uneven wear caused by differences in surface hardness was solved, and high flatness sapphire double-polished wafer processing was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- XUZHOU KAICHENG TECH CO LTD
- Filing Date
- 2025-10-13
- Publication Date
- 2026-07-21
AI Technical Summary
Existing technologies are insufficient for effectively processing sapphire materials with special crystal orientations, resulting in uneven wear due to differences in surface hardness, which makes it difficult to meet the requirements of precision applications.
Large-size sapphire wafers are ground and polished, combined with CNC edge machining, and ink is printed on the wafer surface before processing to protect the surface and ensure flatness.
It improves the surface flatness of sapphire wafers with special crystal orientations, avoids scratches during CNC machining, and meets the needs of precision applications.
Smart Images
Figure CN122425562A_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of sapphire processing technology, and in particular to a processing method for a special crystal orientation sapphire double polished sheet. Background Technology
[0002] Sapphire (commonly known as corundum) has a Mohs hardness second only to diamond and belongs to the trigonal crystal system with a hexagonal structure. In this crystal structure, different crystal orientations of sapphire exhibit selective reflection of X-rays at the molecular level, thus forming specific crystal orientation characteristics. Sapphire with different crystal orientations displays differentiated physical properties: C-oriented sapphire has excellent optical transmittance and is therefore widely used in substrate manufacturing; A-oriented sapphire, due to its higher mechanical hardness, is mainly used as a window material. Besides the standard crystal orientation, sapphire materials also include special crystal orientation variants, such as sapphire that is 20° off-center from the C-oriented orientation. These special crystal orientation materials exhibit performance gradients on the same surface, such as uneven hardness distribution. If conventional grinding and polishing processes are used for C-oriented or A-oriented sapphire, the surface hardness difference will lead to uneven wear after processing, causing surface flatness defects and making it difficult to meet the requirements of precision applications. Therefore, there is an urgent need to develop a dedicated processing method for sapphire with special crystal orientations. Summary of the Invention
[0003] In order to solve the above-mentioned technical problems, or at least partially solve the above-mentioned technical problems, this disclosure provides a processing method for sapphire double polished wafers with special crystal orientation, which can process sapphire double polished wafers with special crystal orientation and high flatness.
[0004] To achieve the above objectives, this disclosure provides a method for processing a special crystal orientation sapphire double-polished wafer, comprising: Step 1: Cut the sapphire crystal rod into sapphire wafers; Step 2: Grinding the sapphire wafer; Step 3: Print ink on the surface of the sapphire wafer; Step 4: Perform CNC edge machining on the sapphire wafer; Step 5: Perform ink stripping on the sapphire wafer; The size of the sapphire wafer in step 1 is 1.3-1.5 times the size of the sapphire wafer in step 5.
[0005] Optionally, the grinding process of the sapphire wafer in step 2 includes: double-sided fine grinding of the sapphire wafer and double-sided polishing of the sapphire wafer.
[0006] Optionally, the double-sided fine grinding of the sapphire wafer is performed using diamond polishing slurry, with a flow rate of 12-18 ml / min and a grinding pressure of 500-600 kg.
[0007] Optionally, the double-sided polishing of the sapphire wafer is performed using a silicon oxide polishing slurry with a flow rate of 5-13 L / min and a polishing pressure of 500-600 Kg.
[0008] Optionally, the ink printing on the sapphire wafer surface in step 3 includes printing ink on the front side of the sapphire wafer and printing ink on the back side of the sapphire wafer.
[0009] Optionally, in step 3, the ink thickness for printing ink on the surface of the sapphire wafer is 10-15 μm.
[0010] Optionally, the CNC edge machining of the sapphire wafer includes: roughing the sapphire wafer and finishing the sapphire wafer.
[0011] Optionally, the sapphire wafer is roughened using a 500# grinding wheel, a spindle speed of 11000-13000 rpm, and a feed rate of 1200 mm / min-1500 mm / min.
[0012] Optionally, the sapphire wafer is finished using a 300# grinding wheel, a spindle speed of 11000-13000 rpm, and a feed rate of 800 mm / min-1000 mm / min.
[0013] Optionally, the crystal orientation of the sapphire wafer is 10°-20° off from the A-C orientation.
[0014] The technical solution provided in this disclosure has the following advantages compared with the prior art: This disclosure discloses a processing method for a special crystal orientation sapphire double-polished wafer. First, a sapphire wafer 1.3-1.5 times larger than the target product size is selected and ground and polished. Then, CNC edge machining is used to process it to the target size. This processing method can effectively improve the surface flatness of the special crystal orientation sapphire wafer. Furthermore, printing ink on both sides of the sapphire wafer before CNC machining can protect the surface of the sapphire wafer from scratches during CNC machining, ensuring that the surface flatness of the sapphire wafer is not affected by the CNC machining process. Attached Figure Description
[0015] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.
[0016] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a flowchart of a processing method for a special crystal orientation sapphire double-polished wafer. Detailed Implementation
[0018] To better understand the above-mentioned objectives, features, and advantages of this disclosure, the solutions disclosed herein will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.
[0019] Numerous specific details are set forth in the following description in order to provide a full understanding of this disclosure, but this disclosure may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some, and not all, of the embodiments of this disclosure. Example
[0020] This embodiment uses a circular, thin-film sapphire product as an example for illustration.
[0021] like Figure 1 As shown, a method for processing a special crystal orientation sapphire double-polished wafer includes: Step 1: Cut the sapphire crystal rod into sapphire wafers.
[0022] In this step, the selected sapphire ingot cross-sectional size is 1.3-1.5 times the size of the target product, and the crystal orientation of the sapphire ingot cross-section is 10°-20° off the C direction. A multi-wire dicing machine in conjunction with diamond wire is used to cut the sapphire ingot into several sapphire wafers. During cutting, the descent speed of the multi-wire dicing machine's table is 12-18 mm / h, and the linear speed of the diamond wire is 600-900 m / min. The crystal orientation of the main face of the cut sapphire wafers is 10°-20° off the C direction. Furthermore, after cutting, the sapphire wafers are cleaned in a multi-tank ultrasonic cleaner.
[0023] It should be noted that in this step, the cross-sectional size of the selected sapphire crystal rod is 1.3-1.5 times the size of the target product, that is, the diameter of the cut circular sapphire slice is 1.3-1.5 times the size of the target product.
[0024] Step 2: Grinding the sapphire wafer.
[0025] The grinding process for sapphire wafers includes double-sided fine grinding and double-sided polishing.
[0026] In this step, the sapphire wafer is finely polished on both sides using a double-sided polishing machine and diamond polishing slurry. The diamond polishing slurry flow rate is 12-18 ml / min, and the polishing pressure is 500-600 kg.
[0027] After grinding, the sapphire wafer is placed in a multi-tank ultrasonic cleaner for cleaning.
[0028] The sapphire wafers are polished on both sides. After double-sided grinding and cleaning, a double-sided grinding device is used with a silicon oxide polishing slurry. The flow rate of the silicon oxide polishing slurry is 5-13 L / min, and the polishing pressure is 500-600 kg. After polishing, the sapphire wafers are placed in a multi-tank ultrasonic cleaner for cleaning.
[0029] Step 3: Print ink on the surface of the sapphire wafer; The process of printing ink on the sapphire wafer surface includes sequentially printing ink on both the front and back sides of the sapphire wafer. The ink thickness on both sides is the same, 10-15µm. After ink printing is completed, the sapphire wafer is placed in a constant-temperature oven for baking.
[0030] Step 4: Perform CNC edge machining on the sapphire wafer; In this step, the sapphire wafer is machined to the target size using CNC edge machining, including roughing and finishing.
[0031] It should be noted that in this step, the sapphire wafer is machined to the target size using CNC edge machining, that is, the diameter of the circular sapphire wafer is machined to the target size.
[0032] The sapphire wafers are roughed using a 500# grinding wheel, a spindle speed of 11,000-13,000 rpm, and a feed rate of 1200-1500 mm / min. The sapphire wafers are then finished using a 300# grinding wheel, a spindle speed of 11,000-13,000 rpm, and a feed rate of 800-1000 mm / min.
[0033] Step 5: Perform ink stripping on the sapphire wafer.
[0034] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.
[0035] The above are merely specific embodiments of this disclosure, enabling those skilled in the art to understand or implement this disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to these embodiments, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A method for processing a special crystal orientation sapphire double-polished wafer, characterized in that, include: Step 1: Cut the sapphire crystal rod into sapphire wafers; Step 2: Grinding the sapphire wafer; Step 3: Print ink on the surface of the sapphire wafer; Step 4: Perform CNC edge machining on the sapphire wafer; Step 5: Perform ink stripping on the sapphire wafer; The size of the sapphire wafer in step 1 is 1.3-1.5 times the size of the sapphire wafer in step 5.
2. The processing method for a special crystal orientation sapphire double-polished wafer according to claim 1, characterized in that, Step 2 involves grinding the sapphire wafer, including double-sided fine grinding and double-sided polishing of the sapphire wafer.
3. The processing method for a special crystal orientation sapphire double-polished wafer according to claim 2, characterized in that, The double-sided fine grinding of the sapphire wafer is performed using diamond polishing slurry with a flow rate of 12-18 ml / min and a grinding pressure of 500-600 kg.
4. The processing method for a special crystal orientation sapphire double-polished wafer according to claim 2, characterized in that, The sapphire wafer is polished on both sides using a silicon oxide polishing slurry with a flow rate of 5-13 L / min and a polishing pressure of 500-600 Kg.
5. The processing method for a special crystal orientation sapphire double-polished wafer according to claim 1, characterized in that, The ink printing on the surface of the sapphire wafer in step 3 includes ink printing on the front side of the sapphire wafer and ink printing on the back side of the sapphire wafer.
6. The processing method for a special crystal orientation sapphire double-polished wafer according to claim 5, characterized in that, In step 3, the ink thickness for printing ink on the surface of the sapphire wafer is 10-15 μm.
7. The processing method for a special crystal orientation sapphire double-polished wafer according to claim 1, characterized in that, The CNC edge machining of the sapphire wafer includes: roughing the sapphire wafer and finishing the sapphire wafer.
8. The processing method for a special crystal orientation sapphire double-polished wafer according to claim 7, characterized in that, The sapphire wafer is roughened using a 500# grinding wheel, a spindle speed of 11000-13000 rpm, and a feed rate of 1200 mm / min-1500 mm / min.
9. The processing method for a special crystal orientation sapphire double-polished wafer according to claim 7, characterized in that, The sapphire wafer is then finished using a 300# grinding wheel, a spindle speed of 11000-13000 rpm, and a feed rate of 800 mm / min-1000 mm / min.
10. The processing method for a special crystal orientation sapphire double-polished wafer according to claim 1, characterized in that, The crystal orientation of the sapphire wafer is 10°-20° off from the A-C direction.