TWI779395B - Rework processing apparatus for removing wafer flaw by plasma etching - Google Patents

Abstract

A Rework processing apparatus for removing wafer flaw by plasma etching a wafer includes a vacuum cavity, a first electrode, a second electrode, an intelligent control module, an etching gas module, and a detection module. The first and second electrodes are disposed in opposite in the vacuum cavity. The etching gas module and the detection module are electrically connected with the intelligent control module. The etching gas module supplies the etching gas between the first and second electrodes. The detection module detects a feature parameter during the etching process. The intelligent module, according to variation of the technical parameter, controls the etching gas module to stop supplying the etching gas. Thus, by intelligently determining the timing for stopping etching, efficiency of the rework process is improved.

Description

Heavy processing equipment for removing wafer defects by plasma etching

The invention relates to plasma etching related equipment, in particular to a heavy processing equipment for removing wafer defects by plasma etching.

Wafers are materials that must be used in semiconductor manufacturing processes and are used as carriers for integrated circuits. Since the material cost of the wafer itself is getting more and more expensive, it is a waste and a pity to directly scrap or discard the defective wafer when the wafer manufacturing process cannot continue due to defects. Faced with such a situation, the current practice is to use rework so that the wafer can be used and processed again, reducing the waste of cost and resources.

However, the traditional rework process (Rework) uses physical grinding to remove the patterns on the wafer surface after sputtering, etching, deposition and other processes, so that the wafer can be patterned again, but the traditional method is easy to damage the wafer The surface of the surface causes the defect to expand, and the finished product grade of the reworked wafer is not high.

Furthermore, during the grinding process, it is necessary to rely on human experience to judge, and to repeatedly confirm whether it has been ground to a better level, so it is quite dependent on manpower, resulting in time-consuming, if the wafer to be reworked (Rework) was previously The process conditions are not the same, which will cause inconvenience and trouble in handling.

In order to solve the above problems, the present invention discloses a rework processing equipment that uses plasma etching to remove wafer defects, which can intelligently determine the trigger time point to stop etching, so that the wafer does not need to manually repeatedly judge whether the rework has been completed during the plasma etching process. It can improve the efficiency of heavy work.

In order to achieve the above object, an embodiment of the present invention provides a heavy processing equipment for removing wafer defects by plasma etching, which is used to perform plasma etching on a wafer, including a vacuum chamber, a first electrode, a second Electrodes, an intelligent control module, an etching gas module and a detection module. The vacuum chamber has a chamber; the first electrode and the second electrode are arranged in the chamber; the second electrode is arranged opposite to the first electrode, there is an etching distance between the second electrode and the first electrode, and the wafer is located in the etching distance The intelligent control module is used to control the heavy processing equipment; the etching gas module is electrically connected to the intelligent control module to supply the etching gas to the etching gap; and the detection module is electrically connected to the intelligent control module for To detect a characteristic parameter in the etching process; wherein, the intelligent control module can control the etching gas module to stop supplying the etching gas according to the change of the characteristic parameter.

In another embodiment, the detection module senses the characteristic parameters with plasma frequency.

In another embodiment, the intelligent control module converts and generates a frequency-time waveform according to characteristic parameters. When a slope of the frequency-time waveform changes from positive to negative, the intelligent control module controls the etching gas module to stop supplying the etching gas.

In another embodiment, the intelligent control module has a time unit, and the time unit can be preset as a number of seconds. The intelligent control module can identify and judge according to the number of seconds. When the slope of the frequency-time waveform changes from positive to negative, and When the occurrence time is less than the number of seconds, the intelligent control module will not stop the etching gas module from supplying the etching gas.

In another embodiment, the detection module uses spectral detection, gas detection, electro-luminescence detection, and image detection to detect characteristic parameters.

In another embodiment, the intelligent control module has a control unit, the control unit can judge and generate a control signal according to the change of the characteristic parameters, and the intelligent control module makes the heavy industrial processing equipment execute the adjustment of various parameters according to the control signal .

In another embodiment, it further includes a judgment module, which is electrically connected to the intelligent control module, and the judgment module can judge the type and thickness of the wafer, and generate a judgment signal to the intelligent control module, and the intelligent control module Group.

In another embodiment, the etching gas module has a gas distribution unit for outputting a predetermined gas corresponding to the wafer.

In another embodiment, it further includes a storage module, which is electrically connected to the intelligent control module, the storage module can store a comparison parameter, the comparison parameter is used for comparison with the characteristic parameter, and the control unit is based on the comparison The difference between the parameter and the characteristic parameter generates a control signal.

Thereby, the present invention can intelligently judge the trigger time point for stopping the etching, without manual confirmation and judgment repeatedly, saving manpower and avoiding the problem of time-consuming operation.

Furthermore, the present invention can use the judging module to preliminarily judge the type of the wafer, and cooperate with the intelligent adjustment of process parameters to improve the efficiency of rework.

1: Heavy industrial processing equipment

2: Wafer

10: Vacuum cavity

11: The first electrode

111: perforation

12: Second electrode

13: chamber

14: High frequency power supply

20: Intelligent control module

21: time unit

30: Etching gas module

31: Gas distribution unit

40: Detection Module

50: Judgment module

60: Storage module

D: Etching pitch

22: Control unit

A: location

B: location

[ Fig. 1 ] is a schematic structural view of heavy industrial processing equipment of the present invention.

[ Fig. 2 ] is a schematic diagram of the control architecture of the heavy industry processing equipment of the present invention.

[ Fig. 3 ] is a schematic diagram of the frequency-time waveform generated according to the characteristic parameters of the present invention.

Exemplary embodiments of the present invention are described in detail below with reference to the accompanying drawings, and it is not intended to limit the technical principles of the present invention to specific disclosed embodiments, but the scope of the present invention is only limited by the scope of the patent application, covering substitutions, modifications and equivalent.

1 to 3, the present invention is a rework processing equipment 1 that uses plasma etching to remove wafer defects, and is used to perform plasma etching on a wafer 2, so that the wafer 2 undergoes rework processing, and It can be used again, avoiding the situation of direct scrapping. The heavy industry processing equipment 1 of the present invention includes a vacuum cavity 10 , a first electrode 11 , a second electrode 12 , an intelligent control module 20 , an etching gas module 30 and a detection module 40 .

The vacuum cavity 10 has a chamber 13, the first electrode 11 and the second electrode 12 are arranged in the chamber 13, the second electrode 12 is opposite to the first electrode 11, and the second electrode 12 and the first electrode 11 There is an etching distance D between them, and the wafer 2 is located at the etching distance D for plasma etching. Wherein, the second electrode 12 is used as a holding platform for carrying the wafer 2 thereon, and the second electrode 12 is electrically connected to a high-frequency power source 14 . The first electrode 11 includes a plurality of through holes 111, so that the etching gas flows into the chamber 13 through the plurality of through holes 111 and flows to the wafer 2 with the etching distance D, and at the same time, a high frequency is applied to the etching distance D through the high frequency power supply 14, In this way, the plasma is generated and the wafer 2 is subjected to the heavy work of plasma etching. In another embodiment, the first electrode 11 and the second electrode 12 are electrically connected to the high-frequency power supply 14, or one electrode is connected to electricity, and the other electrode is grounded, that is, the method used in this case can be a reactive Ion etching (Reactive-Ion Etching, RIE). In addition, the plasma of the present invention includes, but is not limited to, an inductively coupled plasma source (Inductively-Coupled Plasma, ICP), Remote Plasma Source (Remote Plasma Source, RPS), Microwave Plasma Source (Microwave Plasma Source).

The intelligent control module 20 is used to control the heavy processing equipment 1 .

The etching gas module 30 is electrically connected to the intelligent control module 20 for controlling the supply of etching gas to the etching distance D.

The detection module 40 is electrically connected to the intelligent control module 20 to detect a characteristic parameter in the etching process. Wherein, the detection module 40 detects characteristic parameters in the etching process in the chamber 13 , but it is not limited thereto. For example, the characteristic parameters of the wafer 2 , the characteristic parameters of the gas or the characteristic parameters of the plasma are detected in the chamber 13 .

Wherein, the intelligent control module 20 can control the etching gas module 30 to stop supplying the etching gas according to the change of the characteristic parameters. In this way, the heavy processing equipment 1 of the present invention can stop the plasma etching through intelligent judgment based on the changes in the characteristic parameters of the wafer 2, so that manual experience is not required to repeatedly confirm whether the wafer 2 has reached the etching standard, which saves manpower. In addition, the present invention can make intelligent judgments for different types of wafers 2 and wafers 2 of different material thicknesses, avoiding human misjudgment.

In the embodiment of the present invention, the detection module 40 uses the plasma frequency to sense the characteristic parameter, for example, the detection module 40 detects the frequency of the voltage of the high-frequency power supply 14 as the change of the sensing characteristic parameter. The intelligent control module 20 converts and generates a frequency-time waveform (as shown in Figure 3 ) according to the characteristic parameters. The etching gas module 30 stops supplying the etching gas. For example, when the slope of the frequency-time waveform is positive, it means that the strength of the RF signal feedback is positive. At this time, the wafer 2 has not yet reached the required plasma etching level. When the slope of the frequency-time waveform changes from positive to negative , the strength of the RF signal feedback gradually decreases. At this time, through the smart The module 20 can be controlled to control the etching gas module 30 to stop supplying the etching gas, so that the wafer 2 can reach the required plasma etching level. Therefore, when the slope of the frequency-time waveform changes from positive to negative, it can be used as a judgment to stop etching the trigger time point.

In addition, in other embodiments, the detection module 40 detects characteristic parameters by spectral detection, gas detection, electro-optical detection, image detection, etc., and can also achieve changes based on the characteristic parameters. As stop the supply of etching gas or not. For example, with a spectrum detector, a spectrometer is used to detect the plasma in the chamber 13 for spectral analysis, as the basis for the change of characteristic parameters. The gas detector is located in the chamber 13, because the etched substance will become floating matter or gas, and the detection of the gas concentration is used as the basis for the change of the characteristic parameter. For example, laser light detection is used to emit laser light to the wafer 2 in the chamber 13, and the change of the thickness of the wafer 2 is used as the basis for the change of the characteristic parameters, so as to judge the trigger time point of etching stop. For example, if the detector is affected, the light of the wafer 2 changes, and the LAB color judgment is used as the basis for the change of the characteristic parameter, so as to judge the trigger time point of the etching stop.

Moreover, the intelligent control module 20 also includes a time unit 21, and the time unit 21 can preset a number of seconds, and the number of seconds is 5 seconds to 10 seconds. When the plasma etching is just started, the position B of the frequency-time waveform schematic diagram in Figure 3 also produces a situation where the slope changes from positive to negative, but the time in this case is not long, usually less than 10 seconds, Therefore, the intelligent control module 20 can identify and judge according to the number of seconds preset by the time unit 21. When the slope of the frequency-time waveform changes from positive to negative and the occurrence time is lower than the number of seconds, it is determined that it is not necessary to stop the etching. , that is to maintain the supply of etching gas, if it is higher than the preset number of seconds, it is judged that the occurrence point is at position A. At this time, the intelligent control module 20 controls the etching gas module 30 to stop supplying the etching gas. Therefore, a slope change over a short period of time is not considered a trigger point to stop etching.

In the embodiment of the present invention, the intelligent control module 20 has a control unit 22, the control unit 22 can judge and generate a control signal according to the change of the characteristic parameter, and the intelligent control module 20 makes the heavy industrial processing equipment 1 execute various Modulation of item parameters. The embodiment of the present invention also includes a storage module 60, which is electrically connected to the intelligent control module 20. The storage module 60 can store a comparison parameter. The comparison parameter is used for comparison with the characteristic parameter. A control signal is generated for the difference between the parameter and the characteristic parameter. Wherein, the comparison parameter is a preset parameter or a process parameter of the previous etching process, so that when the characteristic parameter changes but the trigger time point for stopping the etching is not reached, the control unit 22 stores the comparison parameter of the module 60 and The characteristic parameters are compared, and the control unit 22 generates a control signal according to the difference between the two, so that the intelligent control module 20 intelligently according to the control signal, so that the heavy industrial processing equipment 1 performs the modulation of gas pressure, voltage intensity, voltage frequency and other parameters , to increase the operating efficiency of plasma etching, and at the same time, intelligent judgment and adjustment can reduce manual repeated confirmation and reduce the number of manual adjustments to equipment.

In the embodiment of the present invention, a judging module 50 is also included, which is electrically connected to the intelligent control module 20 . The judgment module 50 can detect and judge the wafer 2 through the ellipsometer, and then can judge the type and thickness of the wafer 2, and generate a judgment signal to the intelligent control module 20, and the intelligent control module 20 makes the judgment signal according to the judgment signal. The heavy industry processing equipment 1 executes the modulation of various parameters. Thereby, after the judgment module 50 judges the type and thickness of the wafer 2, the intelligent control module 20 correspondingly regulates the gas pressure output by the etching gas module 30, and controls the voltage intensity and voltage frequency output by the high-frequency power supply 14, so as to Increase the efficiency of etching. The type of the wafer 2 includes the material of the wafer 2 and the type of the surface layer of the wafer 2 formed according to different semiconductor manufacturing processes.

In order to clearly increase the etching efficiency, in the embodiment of the present invention, the etching gas module 30 has a gas distribution unit 31 for outputting a predetermined gas corresponding to the wafer 2 . Therefore, for example, when the judgment module 50 judges that the material of the wafer 2 is silicon dioxide (SiO2), the gas distribution unit 31 can select Determine the formula gas mainly based on fluorine gas and enter the chamber 13 through the etching gas module 30 for etching, and when the judgment module 50 judges that the material of the wafer 2 is a low dielectric constant material (low-k material), the gas The distributing unit 31 can select argon-based formula gas and input it into the chamber 13 through the etching gas module 30 for etching. Therefore, according to the present invention, different etching gases can be selected for etching according to different wafer 2 materials. To achieve the purpose of improving the etching efficiency.

Therefore, the present invention has the following advantages:

1. The present invention utilizes intelligent judgment to stop the trigger time point of etching, so that during the plasma etching process of wafers, there is no need for manual repeated judgments and time-consuming operations, which improves the efficiency of heavy work.

2. The present invention utilizes the judgment module to preliminarily judge the type of the wafer, and cooperates with the intelligent adjustment process parameters, so as to perform plasma etching with corresponding parameters according to the type of the wafer, and improve the efficiency of rework.

3. The present invention can use the big data of the storage module to collect the process parameters of the previous etching process, so as to record the trigger time point of stopping the etching, and intelligently judge and adjust, so as to realize the purpose of intelligent processing.

Above, although the present invention is described with a preferred embodiment, those skilled in the art can make various changes without departing from the spirit and scope of the present invention. The aforementioned embodiments are only used to illustrate the present invention, and are not intended to limit the scope of the present invention. All modifications or changes that do not violate the spirit of the present invention belong to the patent scope of the present invention.

1: Heavy industrial processing equipment

2: Wafer

10: Vacuum cavity

11: The first electrode

111: perforation

12: Second electrode

13: chamber

14: High frequency power supply

20: Intelligent control module

21: time unit

30: Etching gas module

31: Gas distribution unit

40: Detection Module

50: Judgment module

60: Storage module

D: Etching pitch

22: Control unit

Claims (9)

A rework processing equipment that uses plasma etching to remove wafer defects is used to perform plasma etching on a wafer, and the rework processing equipment includes: A vacuum chamber having a chamber; a first electrode disposed in the chamber; A second electrode, which is arranged in the chamber and opposite to the first electrode, there is an etching distance between the second electrode and the first electrode, and the wafer is located at the etching distance; An intelligent control module for controlling the heavy processing equipment; An etching gas module is electrically connected to the intelligent control module for supplying etching gas to the etching space; and A detection module is electrically connected to the intelligent control module to detect a characteristic parameter in the etching process; Wherein, the intelligent control module can control the etching gas module to stop supplying the etching gas according to the change of the characteristic parameter. The rework processing equipment for removing wafer defects by plasma etching according to Claim 1, wherein the detection module senses the characteristic parameters at a plasma frequency. The rework processing equipment for removing wafer defects by plasma etching as described in claim 2, wherein the intelligent control module converts and generates a frequency-time waveform according to the characteristic parameter, when a slope of the frequency-time waveform changes from positive to positive When negative, the intelligent control module controls the etching gas module to stop supplying the etching gas. The heavy processing equipment for removing wafer defects by plasma etching as described in claim 3, wherein, the intelligent control module has a time unit, and the time unit can preset a number of seconds, and the intelligent control module can be based on the The number of seconds is used to identify and judge. When the slope of the frequency-time waveform changes from positive to negative and the occurrence time is lower than the number of seconds, the intelligent control module will not stop the etching gas module from supplying the etching gas. The rework processing equipment for removing wafer defects by plasma etching as described in claim 1, wherein the detection module is selected from spectral detection, gas detection, electro-optical detection and image detection The characteristic parameters are detected in the form of groups formed. The heavy processing equipment for removing wafer defects by plasma etching as described in any one of claims 1, 2, and 5, wherein the intelligent control module has a control unit, and the control unit can be based on the change of the characteristic parameter And judging to generate a regulation signal, the intelligent control module makes the heavy industry processing equipment execute the regulation of various parameters according to the regulation signal. The heavy processing equipment for removing wafer defects by plasma etching as described in claim 6 further includes a judging module, which is electrically connected to the intelligent control module, and the judging module can judge the type of the wafer and thickness, and generate a judgment signal to the intelligent control module. The rework processing equipment for removing wafer defects by plasma etching according to Claim 7, wherein the etching gas module has a gas distribution unit for outputting a predetermined gas corresponding to the wafer. The rework processing equipment for removing wafer defects by plasma etching as described in claim 6 further includes a storage module electrically connected to the intelligent control module, the storage module can store a comparison parameter, the The comparison parameter is used for comparison with the feature parameter, and the control unit generates the control signal according to the difference between the comparison parameter and the feature parameter.

Images