Wafer cutting method

Abstract

The present application relates to a semiconductor production method, in particular to a wafer cutting method, which comprises the following steps: attaching a micro-vibration sensor to a spindle; installing a first cutting tool on the spindle and idling to obtain a first vibration value; installing a second cutting tool on the spindle and idling to obtain a second vibration value, the second cutting tool being just able to cause a beveling phenomenon; calculating a beveling threshold vibration value according to the first vibration value and the second vibration value; installing a third cutting tool on the spindle and idling to obtain a third vibration value, the third cutting tool being ready for cutting operation; comparing the third vibration value with the beveling threshold vibration value; if the third vibration value is greater than the beveling threshold vibration value, then dismounting the third cutting tool from the spindle; if the third vibration value is less than the beveling threshold vibration value, then putting the third cutting tool into cutting operation. By attaching a micro-vibration sensor to the spindle and controlling the quality of the cutting tool, the cutting quality can be improved.

Description

Technical Field

[0001] This invention relates to a semiconductor manufacturing method, and more particularly to a wafer dicing method. Background Technology

[0002] The description in this section provides only background information related to the disclosure of this invention and does not constitute prior art.

[0003] Semiconductor products are evolving towards greater precision and miniaturization to meet market demands, leading to increasingly stringent requirements for processing accuracy, particularly in controlling the perpendicularity of the cut surface and the straightness of the cut line during wafer dicing. If the dicing blade is poorly positioned during assembly or is already worn excessively, subsequent wafer dicing operations will significantly reduce wafer quality, potentially even resulting in material scrap. Common problems include two types of dicing defects: skewed cutting and serpentine cutting. Skewed cutting occurs when the dicing blade fails to cut perpendicularly to the wafer surface, causing the cut surface angle to deviate from the ideal vertical direction, resulting in tilted sidewalls instead of vertical ones. Serpentine cutting occurs when the cutting trajectory fails to maintain a straight line, instead exhibiting a curved or undulating pattern, resulting in a serpentine-like cut line. This leads to inconsistent chip dimensions and irregular edges. Both of these issues result in low yield rates.

[0004] In summary, it is generally necessary to monitor the cutting blade to prevent the above-mentioned situations. However, the existing technology for monitoring the cutting blade usually involves directly observing the differences in the cutting blade. The disadvantage is that it can only be detected when there is a significant change in the cutting blade and the blade shape is confirmed. Another method is to analyze the condition of the cutting blade during the cutting process and replace the cutting blade when it is determined that the condition of the cutting blade is slowly deteriorating. However, this method can only be detected when the cutting blade is broken, which is not timely and leads to material waste. Summary of the Invention

[0005] The purpose of this invention is to provide a wafer dicing method that improves dicing quality by attaching a micro-vibration sensor to the spindle and controlling the quality of the dicing blade.

[0006] To achieve the above objectives, the present invention discloses a wafer dicing method; the wafer dicing method includes:

[0007] A micro-vibration sensor is provided, which is attached to the main shaft and is connected to the control mechanism for signal transmission.

[0008] The intact first cutter is installed on the spindle, and the spindle is started to run so that the first cutter spins idle. At this time, the micro-vibration sensor sends the first vibration value obtained to the control mechanism, and then the first cutter is removed from the spindle.

[0009] The second cutter, which will produce a slanted cut, is mounted on the main shaft. The main shaft is started to run, allowing the second cutter to idle. At this time, the micro-vibration sensor sends the obtained second vibration value to the control mechanism, and then the second cutter is removed from the main shaft.

[0010] The vibration value of the obliquely cut threshold is calculated based on the first vibration value and the second vibration value;

[0011] The third cutter, prepared for the cutting operation, is mounted on the spindle. The spindle is started to run, causing the third cutter to idle. At this time, the micro-vibration sensor sends the obtained third vibration value to the control mechanism.

[0012] The third vibration value is compared with the beveled threshold vibration value. If the third vibration value is greater than the beveled threshold vibration value, the third cutter is detached from the spindle. If the third vibration value is less than the beveled threshold vibration value, the third cutter is put into cutting operation.

[0013] Furthermore, after the step of "installing the second cutter that will just produce a slanted cut on the spindle, starting the spindle to run the second cutter while it is idling, at which time the micro-vibration sensor sends the obtained second vibration value to the control mechanism, and then removing the second cutter from the spindle", the method further includes installing a fourth cutter that will just produce a serpentine cut on the spindle, starting the spindle to run the fourth cutter while it is idling, at which time the micro-vibration sensor sends the obtained fourth vibration value to the control mechanism, and then removing the fourth cutter from the spindle;

[0014] The vibration value of the serpentine threshold is calculated based on the first vibration value and the fourth vibration value.

[0015] After the step of "installing the third cutter, which is prepared for the cutting operation, on the spindle, starting the spindle to run so that the third cutter idles, at which time the micro-vibration sensor sends the obtained third vibration value to the control mechanism", the method further includes comparing the third vibration value with the serpentine cutting threshold vibration value. If the third vibration value is greater than the serpentine cutting threshold vibration value, the third cutter is detached from the spindle; if the third vibration value is less than the serpentine cutting threshold vibration value, the third cutter is put into the cutting operation.

[0016] Furthermore, the vibration value of the beveled threshold is set to half of the sum of the first vibration value and the second vibration value, and the vibration value of the serpentine threshold is set to half of the sum of the first vibration value and the fourth vibration value.

[0017] Furthermore, the vibration value of the oblique-cut threshold is set to 103.5 μm / s, and the vibration value of the serpentine-cut threshold is set to 154.5 μm / s.

[0018] Furthermore, an alarm is provided, which is signal-connected to the control mechanism. In the step of "comparing the third vibration value with the chamfered threshold vibration value", if the third vibration value is greater than the chamfered threshold vibration value, the alarm will sound.

[0019] Furthermore, a maximum vibration threshold is set. During the step of "putting the third cutter into the cutting operation", the micro-vibration sensor sends the obtained real-time vibration value to the control mechanism. If the real-time vibration value is greater than the maximum vibration threshold, the cutting operation is stopped and the third cutter is detached from the spindle; if the real-time vibration value is less than the maximum vibration threshold, the cutting operation continues.

[0020] Furthermore, during the step "the real-time vibration value is greater than the maximum vibration threshold value", the alarm sounds.

[0021] Furthermore, the maximum vibration threshold is set to 70 μm / s.

[0022] It also includes a wafer dicing apparatus for the wafer dicing method described above, wherein the wafer dicing apparatus includes a micro-vibration sensor, a spindle, a control mechanism, and an alarm, the micro-vibration sensor is attached to the spindle, and the control mechanism is signal-connected to the spindle, the micro-vibration sensor, and the alarm respectively.

[0023] By employing the above technical solutions, the beneficial effects of the present invention are as follows:

[0024] 1. The wafer dicing method of the present invention can be implemented by attaching a micro-vibration sensor to the spindle. Before the dicing operation, a first dicing blade is first installed and the corresponding first vibration value is measured. Then, a second dicing blade that will produce a slant cutting phenomenon is installed and the corresponding second vibration value is measured. The slant cutting threshold vibration value is calculated based on the first and second vibration values. With the help of the slant cutting threshold vibration value, idle monitoring is performed before the subsequent dicing operation to avoid using a dicing blade that does not meet the usage requirements, which would result in wafer material loss.

[0025] 2. The wafer dicing method of the present invention also provides a serpentine dicing threshold vibration value similar to the oblique dicing threshold vibration value, which allows for flexible selection of the corresponding dicing quality control threshold as needed, avoiding dicing waste and providing greater flexibility.

[0026] 3. The wafer dicing method of the present invention monitors the real-time vibration value through a micro-vibration sensor during the dicing operation, tracks the usage of the dicing blade, and immediately stops the operation when the dicing blade wears out, so as to avoid the loss of wafer material.

[0027] To further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are for reference and illustration only and are not intended to limit the present invention. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments or prior art of this specification, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of vibration value monitoring before wafer dicing, provided in an embodiment of this specification.

[0030] Figure 2 This is a schematic diagram of vibration monitoring after a wafer dicing operation provided in the embodiments of this specification; Detailed Implementation

[0031] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this specification.

[0032] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. Furthermore, the accompanying drawings of the present invention are for simple illustrative purposes only and are not depictions of actual dimensions; this is stated in advance. The following embodiments will further describe the relevant technical content of the present invention in detail, but the disclosed content is not intended to limit the scope of protection of the present invention.

[0033] It should be understood that while terms such as "first," "second," and "third" may be used in this document to describe various components or signals, these components or signals should not be limited by these terms. These terms are primarily used to distinguish one component from another, or one signal from another. Furthermore, the term "or" as used herein should, as appropriate, include any combination of one or more of the related listed items.

[0034] Please see Figure 1-2 This embodiment provides a wafer dicing method; wherein the wafer dicing method includes:

[0035] A micro-vibration sensor is provided and attached to the spindle. The micro-vibration sensor is connected to the control mechanism for signal transmission.

[0036] Install the intact first cutter on the spindle, start the spindle to make the first cutter idle, at which time the micro vibration sensor sends the first vibration value to the control mechanism, and then remove the first cutter from the spindle;

[0037] The second cutter, which will produce a slanted cut, is installed on the spindle. The spindle is started to run, allowing the second cutter to idle. At this time, the micro-vibration sensor sends the obtained second vibration value to the control mechanism, and then the second cutter is removed from the spindle.

[0038] The vibration value of the oblique threshold is calculated based on the first vibration value and the second vibration value;

[0039] The third cutter, prepared for the cutting operation, is installed on the spindle. The spindle is started to run, allowing the third cutter to idle. At this time, the micro-vibration sensor sends the obtained third vibration value to the control mechanism.

[0040] The third vibration value is compared with the beveled threshold vibration value. If the third vibration value is greater than the beveled threshold vibration value, the third cutter is detached from the spindle; if the third vibration value is less than the beveled threshold vibration value, the third cutter is put into cutting operation.

[0041] For the above structure, during installation, the operator first attaches a micro-vibration sensor to the end of the spindle near the cutter mounting point on the original system. Then, the micro-vibration sensor is connected to the signal of the external control mechanism, and the alarm is also connected to the signal of the control mechanism. This allows the micro-vibration sensor to effectively detect the vibration transmitted by the cutter on the spindle and transmit the vibration data to the control mechanism. At the same time, the control mechanism can also transmit information to the alarm in a timely manner so that it can promptly issue a sound alert to the operator.

[0042] In this embodiment, a vibration value data pre-reading stage is first performed. The operator installs the first cutter on the spindle and starts the spindle to idle, allowing the micro-vibration sensor to record the vibration value of the first cutter and transmit it to the control mechanism. The first cutter is set to be a good cutter, meaning it is a new cutter that has not been worn and meets the standard requirements for a good product. Furthermore, the first cutter is installed correctly, without any misalignment relative to the spindle or other abnormal installation that would affect its use. Figure 1 As shown on the left, the first cutter continuously idles for a preset interval, and the first vibration value of the first cutter is finally recorded as 83um / s.

[0043] Similarly, the operator removes the first cutter from the spindle and installs the second cutter, which will just produce a beveling effect. The second cutter is then allowed to idle on the spindle, causing a micro-vibration sensor to record its vibration value and transmit it to the control mechanism. The second cutter is designed to produce a beveling effect; that is, after use, during the previous cutting process, as it transitioned from a normal cutting state to a state where beveling might occur, observations of its vibration value or other methods revealed that it had just reached the critical point where further use would result in a beveling effect. In other words, the wear level of the second cutter is between that of a good cutter and a bad cutter. Figure 1 As shown in the middle, the second cutter continuously idles for a preset interval, and the final recorded second vibration value of the second cutter is 124um / s.

[0044] Subsequently, based on the first and second vibration values ​​obtained above, and considering cost and processing efficiency in this embodiment, the bevel threshold vibration value is set to 103.5 μm / s, calculated as half the sum of the first and second vibration values. Then, the third cutter is installed on the spindle and continuously idled for a preset period, and the third vibration value of the third cutter is monitored. In one embodiment, the third vibration value is 110 μm / s, which is greater than the bevel threshold vibration value of 103.5 μm / s. Therefore, it can be determined that the lifespan of the third cutter installed at this time is short, affecting the processing efficiency of wafer dicing. After obtaining the above information, the control mechanism triggers the alarm to sound, prompting the operator to replace the third cutter and perform maintenance or replace it with another cutter. In another embodiment, the third vibration value is 89um / s, which is less than the 103.5um / s set for the bevel threshold vibration value. Therefore, it can be determined that the lifespan of the third cutter installed at this time is relatively long. After installation, it can maintain long-term operation without affecting the processing efficiency of wafer cutting. Thus, the third cutter can be further put into subsequent cutting operations.

[0045] It is worth noting that the idle time of the spindles of the first, second, and third cutters is the same to maintain the standardization of vibration value data. In the above embodiment, the control mechanism can also be connected to the spindle signal. When the control mechanism obtains a third vibration value that is greater than the vibration value of the oblique cutting threshold, the control mechanism drives the spindle to stop, causing the third cutter to stop rotating, and at the same time, it also drives the alarm to sound.

[0046] In one embodiment, after the step of "installing a second cutter that will produce a beveled cut on the spindle, starting the spindle to allow the second cutter to idle, at which point the micro-vibration sensor sends the obtained second vibration value to the control mechanism, and then detaching the second cutter from the spindle," the method further includes installing a fourth cutter that will produce a serpentine cut on the spindle, starting the spindle to allow the fourth cutter to idle, at which point the micro-vibration sensor sends the obtained fourth vibration value to the control mechanism, and then detaching the fourth cutter from the spindle. Similar to the method for setting the beveled cut threshold vibration value described above, the serpentine cut threshold vibration value is calculated based on the first and fourth vibration values. Then, the method further includes comparing the third vibration value with the serpentine cut threshold vibration value. If the third vibration value is greater than the serpentine cut threshold vibration value, the third cutter is detached from the spindle; if the third vibration value is less than the serpentine cut threshold vibration value, the third cutter is put into cutting operation. Specifically, in this embodiment, the fourth vibration value is set to 226 μm / s, resulting in a serpentine cut threshold vibration value of 154.5 μm / s.

[0047] Using the above method, considering that in some wafer dicing scenarios, the requirement to avoid oblique cuts is not high, but the requirement to avoid serpentine cuts is, a serpentine cut threshold vibration value can be set, which in this embodiment serves as a standard for whether the dicing blade can continue to be used. Specifically, when the third vibration value of the third dicing blade is greater than the oblique cut threshold vibration value but less than the serpentine cut threshold vibration value, the third dicing blade can still be used in subsequent dicing operations, avoiding blade waste.

[0048] In one embodiment, a maximum vibration threshold is set. During the step of "putting the third cutter into the cutting operation," the micro-vibration sensor sends the obtained real-time vibration value to the control mechanism. If the real-time vibration value is greater than the maximum vibration threshold, the cutting operation is stopped and the third cutter is detached from the spindle; if the real-time vibration value is less than the maximum vibration threshold, the cutting operation continues. Specifically, in this embodiment, the maximum vibration threshold is set to 70 μm / s. Figure 2As shown, during the wafer dicing process, a micro-vibration sensor monitors and acquires the real-time vibration value of the third cutter. The real-time vibration value increases with normal wear and tear of the cutter during use. The maximum bevel cutting value for the wafer material is 20mm. When the real-time vibration value exceeds 70µm / s, the bevel cutting value is greater than 20mm, failing to meet the standard. Continuing production at this point would waste material, so the control mechanism triggers an alarm to alert the operator to replace the third cutter. In the above embodiment, the control mechanism can also be connected to the spindle signal. When the control mechanism obtains a real-time vibration value greater than 70µm / s, it stops the spindle, causing the third cutter to stop rotating, allowing the operator to quickly replace the third cutter. Through this method, by monitoring the real-time vibration value, the dicing quality is effectively monitored, avoiding material waste.

[0049] The content disclosed above is only a preferred and feasible embodiment of the present invention, and is not intended to limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made using the contents of the present invention specification and drawings are included in the scope of the patent application of the present invention.

[0050] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0051] Although this application has been described by way of examples, those skilled in the art will know that this application has many modifications and variations without departing from the spirit of this application, and the appended embodiments include these modifications and variations without departing from this application.

Claims

1. A wafer dicing method; characterized in that, The wafer dicing method includes: A micro-vibration sensor is provided, which is attached to the main shaft and is connected to the control mechanism for signal transmission. The intact first cutter is installed on the spindle, and the spindle is started to run so that the first cutter spins idle. At this time, the micro-vibration sensor sends the first vibration value obtained to the control mechanism, and then the first cutter is removed from the spindle. The second cutter, which will produce a slanted cut, is mounted on the main shaft. The main shaft is started to run, allowing the second cutter to idle. At this time, the micro-vibration sensor sends the obtained second vibration value to the control mechanism, and then the second cutter is removed from the main shaft. The vibration value of the obliquely cut threshold is calculated based on the first vibration value and the second vibration value; The third cutter, prepared for the cutting operation, is mounted on the spindle. The spindle is started to run, causing the third cutter to idle. At this time, the micro-vibration sensor sends the obtained third vibration value to the control mechanism. The third vibration value is compared with the beveled threshold vibration value. If the third vibration value is greater than the beveled threshold vibration value, the third cutter is detached from the spindle. If the third vibration value is less than the beveled threshold vibration value, the third cutter is put into cutting operation.

2. The wafer dicing method according to claim 1, characterized in that: After the step "installing the second cutter that will just produce a slanted cut on the spindle, starting the spindle to run the second cutter while it is idling, at which time the micro-vibration sensor sends the obtained second vibration value to the control mechanism, and then removing the second cutter from the spindle", the method further includes installing a fourth cutter that will just produce a serpentine cut on the spindle, starting the spindle to run the fourth cutter while it is idling, at which time the micro-vibration sensor sends the obtained fourth vibration value to the control mechanism, and then removing the fourth cutter from the spindle; The vibration value of the serpentine threshold is calculated based on the first vibration value and the fourth vibration value. After the step "installing the third cutter prepared for cutting operations on the spindle, starting the spindle to run the third cutter idling, at which time the micro-vibration sensor sends the obtained third vibration value to the control mechanism", the method further includes comparing the third vibration value with the serpentine cutting threshold vibration value. If the third vibration value is greater than the serpentine cutting threshold vibration value, the third cutter is detached from the spindle; if the third vibration value is less than the serpentine cutting threshold vibration value, the third cutter is put into cutting operations.

3. The wafer dicing method according to claim 2, characterized in that: The vibration value of the beveled threshold is set to half of the sum of the first vibration value and the second vibration value, and the vibration value of the serpentine threshold is set to half of the sum of the first vibration value and the fourth vibration value.

4. The wafer dicing method according to claim 3, characterized in that: The vibration value of the oblique-cut threshold is set to 103.5 μm / s, and the vibration value of the serpentine-cut threshold is set to 154.5 μm / s.

5. The wafer dicing method according to claim 1, characterized in that: An alarm is provided, which is signal-connected to the control mechanism. In the step of "comparing the third vibration value with the vibration value of the beveled threshold", if the third vibration value is greater than the vibration value of the beveled threshold, the alarm will sound.

6. The wafer dicing method according to claim 5, characterized in that: During the step of "putting the third cutter into the cutting operation", the micro-vibration sensor sends the real-time vibration value to the control mechanism. If the real-time vibration value is greater than the maximum vibration threshold, the cutting operation is stopped and the third cutter is detached from the spindle. If the real-time vibration value is less than the maximum vibration threshold, the cutting operation continues.

7. The wafer dicing method according to claim 6, characterized in that: During the step "the real-time vibration value is greater than the maximum vibration threshold value", the alarm sounds.

8. The wafer dicing method according to claim 6, characterized in that: The maximum vibration threshold is set to 70 μm / s.

9. A wafer dicing apparatus, wherein the wafer dicing apparatus is used in the wafer dicing method according to any one of claims 1-8, characterized in that, The wafer dicing apparatus includes a micro-vibration sensor, a spindle, a control mechanism, and an alarm. The micro-vibration sensor is attached to the spindle, and the control mechanism is connected to the spindle, the micro-vibration sensor, and the alarm.

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