KR20160025775A - Apparatus for Manufacturing Wafer - Google Patents

Apparatus for Manufacturing Wafer Download PDF

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Publication number
KR20160025775A
KR20160025775A KR1020140113062A KR20140113062A KR20160025775A KR 20160025775 A KR20160025775 A KR 20160025775A KR 1020140113062 A KR1020140113062 A KR 1020140113062A KR 20140113062 A KR20140113062 A KR 20140113062A KR 20160025775 A KR20160025775 A KR 20160025775A
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KR
South Korea
Prior art keywords
wafer
grinding
chuck table
etching
rotary drum
Prior art date
Application number
KR1020140113062A
Other languages
Korean (ko)
Inventor
공순현
Original Assignee
주식회사 엘지실트론
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Filing date
Publication date
Application filed by 주식회사 엘지실트론 filed Critical 주식회사 엘지실트론
Priority to KR1020140113062A priority Critical patent/KR20160025775A/en
Publication of KR20160025775A publication Critical patent/KR20160025775A/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02002—Preparing wafers
    • H01L21/02005—Preparing bulk and homogeneous wafers
    • H01L21/02008—Multistep processes
    • H01L21/0201—Specific process step
    • H01L21/02013—Grinding, lapping
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02002—Preparing wafers
    • H01L21/02005—Preparing bulk and homogeneous wafers
    • H01L21/02008—Multistep processes
    • H01L21/0201—Specific process step
    • H01L21/02019—Chemical etching
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
    • H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
    • H01L21/30604—Chemical etching
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/67005—Apparatus not specifically provided for elsewhere
    • H01L21/67011—Apparatus for manufacture or treatment
    • H01L21/67092—Apparatus for mechanical treatment
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/677—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for conveying, e.g. between different workstations
    • H01L21/67763—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for conveying, e.g. between different workstations the wafers being stored in a carrier, involving loading and unloading
    • H01L21/67766—Mechanical parts of transfer devices
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/677—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for conveying, e.g. between different workstations
    • H01L21/67763—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for conveying, e.g. between different workstations the wafers being stored in a carrier, involving loading and unloading
    • H01L21/67778—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for conveying, e.g. between different workstations the wafers being stored in a carrier, involving loading and unloading involving loading and unloading of wafers

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  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Robotics (AREA)
  • Mechanical Treatment Of Semiconductor (AREA)

Abstract

The present invention relates to an apparatus for manufacturing a wafer, which performs grinding a wafer by arranging the wafer on a chuck table prepared on a rotation drum, and moving the chuck table to a lower part of a grinding wheel located on an upper part of the rotation drum. The apparatus of the present invention includes: a transfer part which loads the wafer to be ground on the chuck table, and unloads the ground wafer from the chuck table; a grinding part which performs grinding the loaded wafer by making the grinding wheel contact the loaded wafer; and an etching part for performing etching the wafer completed with a grinding process. The grinding part and the etching part are arranged on the same rotation drum, and can perform grinding or etching the wafer according to the movement of the chuck table prepared on the rotation drum. Therefore, productivity of the wafer can be increased since an etching process can be carried out in the same equipment without moving the wafer after the grinding process of grinding a single surface of the wafer is completed, during a process of manufacturing the wafer.

Description

[0001] Apparatus for Manufacturing Wafer [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer manufacturing apparatus, and more particularly, to a wafer manufacturing apparatus capable of performing an etching process on a wafer in the same equipment after performing a grinding process on the wafer.

Generally, silicon wafers used for producing electronic components such as semiconductor devices can be manufactured through various steps.

First, polysilicon is filled in a crucible in a reaction chamber, and a silicon single crystal ingot having a predetermined length and diameter is grown by rotating the crucible. Then, a slicing process for thinly cutting the grown single crystal silicon ingot, a lapping process for maintaining the thickness and flatness of the cut wafer, an etching process for removing impurities and defects etching is performed.

Further, a grinding process for grinding the surface of the sliced silicon wafer and controlling the thickness and flatness of the silicon wafer is additionally performed. In this case, the grinding step includes an etching step for grinding both surfaces of the wafer, and an etching step for removing impurities generated in the grinding step after grinding on the wafer. In addition, the grinding step includes grinding the both surfaces of the wafer Both-side grinding of the wafer can be performed by the grinding apparatus. When grinding on both sides of the wafer is completed, the etching process can be performed again to remove impurities and damage generated in the double-side grinding process.

Then, the wafer can be manufactured through steps such as a polishing process and a subsequent cleaning process to improve the damage of the wafer surface and the flatness of the wafer.

1 and 2 are schematic views of a general wafer grinding apparatus. FIG. 1 is a plan view of a wafer grinding apparatus, and FIG. 2 is a side view of a rotary drum in a wafer grinding apparatus. 1 and 2, the wafer grinding apparatus 10 includes a rotary drum 11, a chuck table 12 placed on a rotary drum, and a spindle 13 located at the top of the chuck table 12 And a transfer robot 15 for transferring the wafer to be polished from the cassette 16 to the chuck table 12 may be disposed at one side of the rotary drum 11. [

The wafer w is loaded on the chuck table 12 located at B by the transfer robot 15 and the spindle 13 descends to grind the wafer with the diamond wheel attached to the spindle 13. [ When the grinding is completed, the rotary drum 11 is rotated to move the chuck table at the position B to the position A, another wafer is loaded to the chuck table at the position B, and while the other grinding of the wafer is proceeding, Is unloaded to the cassette 16 after being cleaned with ultra pure water.

When grinding of the wafer is completed, the cassette 16 is moved to a wet bath consisting of a KOH bath and an ultrapure water bath, dipped in the bath, and treated in each bath for a certain period of time. In order to perform such an etching process, the wafer must be unloaded from the pretreatment apparatus and then loaded and unloaded by the etching apparatus again, which complicates the process and increases the process cost.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a wafer manufacturing apparatus capable of performing a grinding and etching process in one wafer manufacturing apparatus by simplifying a conventional wafer processing step.

In an embodiment of the present invention, a wafer is placed on a chuck table provided on a rotary drum, and the chuck table is moved to a lower part of the grinding wheel located above the rotary drum to perform grinding on the wafer. A transfer unit for loading the chuck table and for unloading the wafer from the chuck table; A grinding unit for grinding the loaded wafer by contacting the grinding wheel; Wherein the grinding portion and the etching portion are disposed on the same rotary drum, and the grinding portion and the etching portion are disposed on the same rotary drum, Etching can be performed.

The etching unit includes a supply line for supplying an etchant on the wafer, a supply nozzle connected to one end of the supply line and for spraying a predetermined etchant onto the wafer, and a supply line connected to the other end of the supply line, And an etchant supply device for supplying an etchant. The etchant can be etched on the chuck table on the chuck table at a position corresponding to the grinding portion.

The grinding unit may include a rotary drum for changing the position of the ground wafer, a chuck table on which the wafer is loaded on the rotary drum, and a spindle positioned on the chuck table and performing grinding on the wafer.

The transfer unit may include a cassette having a predetermined number of wafers loaded thereon; And a transfer robot for loading the wafer from the cassette to the chuck table of the grinding unit or for unloading the wafer from the chuck table of the etching unit to the cassette.

The wafer manufacturing apparatus according to the present invention can perform the etching process on the same equipment without moving the wafer after completing the grinding process for grinding the cross section of the wafer in the process of manufacturing the wafer, thereby increasing the productivity of the wafer .

The wafer manufacturing apparatus of the present invention is etched using the space above the rotary drum on which the wafer is ground, thereby reducing the unit cost of the wafer manufacturing apparatus and reducing the manufacturing cost of the wafer.

1 is a plan view showing a general wafer grinding apparatus
2 is a cross-sectional view showing a side surface of a general wafer grinding apparatus
3 is a plan view showing a wafer manufacturing apparatus according to an embodiment of the present invention.
4 is a cross-sectional view showing a wafer manufacturing apparatus according to an embodiment of the present invention
5 is a flowchart illustrating a method of manufacturing a wafer according to an embodiment of the present invention.

The embodiments of the present invention will be described in detail with reference to the accompanying drawings, but the present invention is not limited to these embodiments. In describing the present invention, a detailed description of well-known functions or constructions may be omitted for the sake of clarity of the present invention.

3 is a plan view showing a wafer manufacturing apparatus according to an embodiment of the present invention.

Referring to FIG. 3, the wafer manufacturing apparatus 20 of the embodiment includes a transfer section for loading a wafer to be ground and unloading the ground wafer, a grinding section for performing grinding on the loaded wafer, And an etching part for performing etching.

The grinding unit includes a rotary drum 21 for changing the position of a wafer subjected to grinding, a chuck table 22 on which a wafer is loaded on the rotary drum 21, And a spindle 23 for performing a grinding for grinding.

The chuck table 21 may be formed as a pair on the rotary drum 21 and may be moved to the grinding part or the etching part by the rotation of the rotary drum 21. [

The spindle 23 moves downward from the upper portion of the chuck table 22 and grinds one surface of the wafer with a grinding wheel provided on the spindle 23. That is, the grinding portion may be the chuck table 22 positioned at the lower portion B of the spindle 23. The spindle 23 is provided with a grinding wheel made of diamond, and the grinding wheel can be contacted through the central portion of the wafer as the spindle is driven up and down. When the wafer and the grinding wheel are brought into contact with each other, the spindle equipped with the grinding wheel and the chuck table on which the wafer is attracted can be rotated to perform grinding on one side of the wafer.

FIG. 4 is a cross-sectional view of a wafer manufacturing apparatus according to an embodiment of the present invention. FIG. 3 specifically shows a cross-section of region A in the rotary drum in FIG.

Referring to FIG. 4, the etching unit includes a supply line 24 for supplying an etchant on the wafer, a supply nozzle 28 connected to one end of the supply line 24 and spraying a predetermined etchant onto the wafer, And an etchant supply device 25 connected to the other end of the supply line 24 and supplying the etchant to the supply line 24. KOH or aqueous NaOH solution may be stored in the etchant supply device 25 and used as an etchant.

The etched portion may be provided on the chuck table 22, which is located at the point A where the wafer positioned in the grinding portion is moved 180 degrees by the rotary drum. That is, the etching portion is provided on a chuck table at a position corresponding to the grinding portion, and the wafer is ground by the grinding portion.

The etching liquid scattering prevention cover 29 may be provided to surround the chuck table 22 corresponding to the etching unit and to prevent scattering of the etching liquid sprayed from the supply nozzle 28. A discharge line 26 connected to the chuck table 22 inside the etchant scattering prevention cover 29 can be formed. The etchant scattering prevention cover 29 and the supply line 24 are moved upward while the rotary drum 21 is rotating so as not to affect the rotation of the rotary drum and the chuck table, When movement is completed, descend again.

The transfer unit may include a cassette 32 on which a predetermined number of wafers are stacked and a transfer robot 31 disposed between the cassette 32 and the rotary drum 21. [

The transfer robot 31 may include a transfer robot 31 for loading a wafer from the cassette 32 to the grinding unit or for unloading the wafer from the etching unit to the cassette.

That is, when the wafer W is loaded on the chuck table 22 at the point B which is the grinding portion by the transfer robot 31, the spindle 23 descends to start grinding on the one surface of the wafer. When grinding is completed, The drum 21 is rotated by 180 degrees to move the ground wafer to the etching point A. A supply nozzle 28 and a supply line 24 for supplying an etchant are formed at an upper portion of the point A so that the etch process can be performed by spraying the etchant onto the wafer.

5 is a flowchart illustrating a method of manufacturing a wafer according to an embodiment of the present invention. Referring to FIG. 5, a wafer manufacturing method includes a growing step S1 of growing a rod-shaped silicon ingot by injecting a solid raw material and a dopant into a crucible disposed inside a single crystal growth chamber, A lapping process step (S2) of slicing the wafer into thin slices, removing the saw marks on the front and back surfaces of the wafer, cutting the wafer thickness to an appropriate level, and removing the stress generated in the slicing process S3) and an etching process for removing minute cracks or defects on the surface of the wafer caused in the lapping process by using the etching solution.

A wafer grinding process (S4) is performed to grind the surface of the sliced silicon wafer to control the thickness and flatness of the silicon wafer. After the grinding process is finished, etching is performed to remove impurities generated in the grinding process The process can be carried out. In order to improve the quality of the wafer, a double-side grinding process and an etching process (S5) may be additionally performed.

At this time, in the wafer grinding step (S4), the end face of the wafer placed on the chuck table is ground by the descent of the grinding wheel disposed on the rotary drum, and when the grinding on the end face of the wafer is finished, And is moved to the etching part according to the rotation. The etching unit may perform an etching process to remove impurities and damage generated in the wafer grinding process by spraying an etching liquid onto the wafer.

In this embodiment, the wafer grinding process and the etching process performed in step S4 may be performed in one equipment. In the embodiment, since the grinding of the wafer is performed on the rotary drum and the etching of the ground wafer is performed, the step of loading and unloading the wafer with the etching equipment can be omitted.

Then, the etched wafer is subjected to a two-step polishing step (S6) to remove defects or residues on the surface thereof, remove particles, metal contaminants, and the like on the surface through a cleaning step (S7) A final wafer can be produced.

As described above, the present invention can increase the productivity of the wafer by performing the grinding process for grinding the end face of the wafer and the etching process in the same equipment in the manufacturing process of the wafer.

In addition, since the wafer manufacturing apparatus of the present invention is etched using the space above the rotary drum on which the wafer is ground, the unit cost of the wafer manufacturing apparatus is reduced and the manufacturing cost of the wafer can be reduced.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood that various modifications and applications other than those described above are possible. For example, each component specifically shown in the embodiments of the present invention can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

20: wafer manufacturing apparatus
21: rotary drum
22: Chuck table
23: Spindle
24: Supply line
25: etching liquid supply device
26: discharge line
28: Feed nozzle
29: Etchant splash-proof cover
31: Transfer robot
32: Cassette

Claims (11)

An apparatus for placing a wafer on a chuck table provided on a rotary drum and moving the chuck table to a lower part of a grinding wheel located above the rotary drum to perform grinding on the wafer,
A transfer unit for loading a wafer to be ground into the chuck table, and unloading the ground wafer from the chuck table;
A grinding unit for grinding the loaded wafer by contacting the grinding wheel; And
And an etch portion for performing an etch on the ground wafer,
Wherein the grinding portion and the etching portion are disposed on the same rotary drum and grinding or etching is performed on the wafer in accordance with movement of the chuck table provided on the rotary drum. The method according to claim 1,
The grinding portion
A rotary drum for changing the position of the wafer to be ground;
A chuck table on which the wafer is loaded on the rotary drum,
A grinding wheel located on the chuck table for performing grinding on the wafer, and a spindle for rotating the grinding wheel. 3. The method of claim 2,
Wherein the chuck table is a pair and is moved to the grinding portion or the etching portion by rotation of the rotary drum. 3. The method of claim 2,
Wherein the spindle moves downward from an upper portion of the chuck table to grind one surface of the wafer with a grinding wheel provided on the spindle. The method according to claim 1,
The etching portion
A supply line for providing etchant on the wafer,
A supply nozzle connected to one end of the supply line for spraying a predetermined etchant onto the wafer,
And an etchant supply device connected to the other end of the supply line and supplying the etchant to the supply line,
And performs an etching process on the ground wafer on the chuck table at a position corresponding to the grinding portion. 6. The method of claim 5,
And an etchant scattering prevention cover which is disposed so as to surround the chuck table corresponding to the etching unit and prevents scattering of the etching solution. The method according to claim 6,
Wherein the etchant is a KOH or aqueous NaOH solution. The method according to claim 6,
And a discharge line for discharging the etchant is connected to a lower portion of the rotary drum in an outer peripheral region of the chuck table. The method according to claim 1,
The conveying portion
A cassette in which a predetermined number of wafers are stacked;
And a transfer robot for loading the wafer from the cassette to the chuck table of the grinding portion or for unloading the wafer from the chuck table of the etching portion to the cassette. 10. The method of claim 9,
Wherein the transfer robot simultaneously performs loading and unloading of the wafer attracted to the chuck table. The method according to claim 1,
Wherein the grinding of the loaded wafer and the etching of the grinding completed wafer are simultaneously performed.
KR1020140113062A 2014-08-28 2014-08-28 Apparatus for Manufacturing Wafer KR20160025775A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020140113062A KR20160025775A (en) 2014-08-28 2014-08-28 Apparatus for Manufacturing Wafer

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020140113062A KR20160025775A (en) 2014-08-28 2014-08-28 Apparatus for Manufacturing Wafer

Publications (1)

Publication Number Publication Date
KR20160025775A true KR20160025775A (en) 2016-03-09

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Family Applications (1)

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KR1020140113062A KR20160025775A (en) 2014-08-28 2014-08-28 Apparatus for Manufacturing Wafer

Country Status (1)

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KR (1) KR20160025775A (en)

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