TW202302307A - System and method for producing silicon wafer and monocrystalline silicon rod - Google Patents

Abstract

The embodiment of the invention discloses a system and method for producing a silicon wafer and a silicon single crystal rod, and the system comprises a marking unit which is used for marking the peripheral surface of the silicon single crystal rod with marks with different characters along the axis direction of the silicon rod; the slicing unit is used for carrying out cutting operation on the single crystal silicon rod so as to cut the single crystal silicon rod into a plurality of silicon wafers; the processing unit is used for carrying out processing operation on the plurality of silicon wafers, and the orientations of the plurality of silicon wafers relative to each other are changed during the processing operation; and the determining unit is used for determining the positions of the complete silicon wafers which are not broken in the cutting operation period and/or the processing operation period in the plurality of silicon wafers relative to each other before the processing operation according to the identifiers.

Description

A system and method for producing silicon wafers and single crystal silicon rods

The invention belongs to the technical field of silicon wafer production, and in particular relates to a system, method and single crystal silicon rod for producing silicon wafers.

Silicon wafers can be obtained after the monocrystalline silicon ingots drawn by the Czochralski method are diced. Currently, the monocrystalline silicon ingots are generally cut by multi-wire cutting. In the multi-wire cutting step, multiple cutting wires in the same plane and parallel to each other reciprocate at a high speed along their own extension direction under the condition of adhering slurry abrasives, and at the same time, they are bonded to the single crystal silicon on the resin plate. The rod is driven in such a way that its longitudinal axis is parallel to the plane of the multiple cutting lines and perpendicular to the cutting lines to generate a feed motion relative to the multiple cutting lines, whereby the silicon rod is cut into A number of circular silicon wafers bonded to a resin board.

Afterwards, various treatments need to be carried out on the above-mentioned silicon wafers. For example, since the surface of the cut silicon wafers is adhered to slurry-like abrasives, it is necessary to pull the silicon wafers away from the resin plate and put the silicon wafers into the cleaning tank for cleaning to remove the adhesion. Slurry abrasive on the surface of the silicon wafer, after which the cleaned silicon wafer needs to be put into the wafer card holder, so that the identity of the corresponding silicon wafer can be generated on each silicon wafer, such as in a single crystal silicon rod The identifier for the position in .

During the above-mentioned various processing operations, the orientations of the plurality of silicon wafers bonded to the resin plate relative to each other may change, making it impossible to determine the orientation of the plurality of silicon wafers relative to each other when they are bonded to the resin plate. The position further causes the multiple silicon chips to be put into the silicon chip clip in a relative positional relationship different from the position relative to each other when bonding on the resin board, such as a different arrangement order, and the sequence is fixed. When the sequence of identification words corresponds to the corresponding positions of the multiple silicon wafers, there will be a deviation between the position information represented by the identification words and the actual position of the silicon wafers in the single crystal silicon ingot, which will lead to the confirmation of the quality of the subsequent single crystal silicon ingots There are errors.

In order to solve the above technical problems, the embodiment of the present invention expects to provide a system, method and single crystal silicon rod for producing silicon wafers, which can change the orientations of multiple silicon wafers cut out of the single crystal silicon rod relative to each other. , to determine the position of the silicon wafer in the silicon rod.

Technical scheme of the present invention is realized like this:

In a first aspect, an embodiment of the present invention provides a system for producing silicon wafers, the system comprising: A marking unit, which is used to mark marks with different properties along the direction of the silicon rod axis on the peripheral surface of the single crystal silicon rod; a slicing unit, the slicing unit is used for cutting the single crystal silicon rod to cut the single crystal silicon rod into a plurality of silicon wafers; a processing unit for performing a processing operation on the plurality of wafers, wherein the orientation of the plurality of wafers relative to each other is changed during the processing operation; A determination unit, configured to determine, according to the identification, the positions of intact silicon wafers that have not been broken during the cutting operation and/or during the processing operation relative to each other before the processing operation.

In a second aspect, an embodiment of the present invention provides a method for producing silicon wafers, the method comprising: Mark the outer peripheral surface of the single crystal silicon rod with markings with different properties along the direction of the silicon rod axis; performing a cutting operation on the single crystal silicon rod to cut the single crystal silicon rod into a plurality of silicon wafers; performing a processing operation on the plurality of wafers, wherein the orientation of the plurality of wafers relative to each other is changed during the processing operation; Based on the identification, the positions of intact silicon wafers of the plurality of wafers that were not broken during the cutting operation and/or during the processing operation relative to each other before the processing operation are determined.

In the third aspect, the embodiment of the present invention provides a single crystal silicon rod, which is used to obtain a plurality of silicon wafers through cutting operation, and the outer peripheral surface of the single crystal silicon rod is formed with a direction along the axis of the silicon rod An identifier with different properties, so that when the orientations of the plurality of silicon wafers relative to each other change during subsequent processing operations, it is possible to determine which of the plurality of silicon wafers is during the cutting operation and/or the processing operation according to the identifier. The position of intact silicon wafers that did not break during the operation relative to each other prior to the processing operation.

Embodiments of the present invention provide a system and method for producing silicon wafers and single crystal silicon ingots, which can use markings with different properties along the axis of the silicon ingots to combine complete silicon wafers with those before processing operations or in other words. The single crystal silicon rods are placed in the same relative positional relationship relative to each other. When the identification word sequence with a fixed order corresponds to the corresponding silicon chip position of the plurality of silicon chips, the identification words represent such as position information and There will be no deviation in the actual position of the complete silicon wafer in the monocrystalline silicon rod.

In order for Ligui examiners to understand the technical characteristics, content and advantages of the present invention and the effects it can achieve, the present invention is hereby combined with the accompanying drawings and appendices, and is described in detail in the form of embodiments as follows, and the drawings used therein , the purpose of which is only for illustration and auxiliary instructions, and not necessarily the true proportion and precise configuration of the present invention after implementation, so it should not be interpreted based on the proportion and configuration relationship of the attached drawings, and limit the application of the present invention in actual implementation The scope is described first.

In the description of the embodiments of the present invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical" , "horizontal", "top", "bottom", "inner", "outer" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description , rather than indicating or implying that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and thus should not be construed as limiting the invention.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the embodiments of the present invention, "plurality" means two or more, unless otherwise specifically defined.

In the embodiments of the present invention, terms such as "installation", "connection", "connection" and "fixation" should be interpreted in a broad sense unless otherwise clearly specified and limited. Disassembled connection, or integration; it can be mechanical connection or electrical connection; it can be direct connection or indirect connection through an intermediary, and it can be the internal communication of two components or the interaction relationship between two components. Those with ordinary knowledge in the art can understand the specific meanings of the above terms in the embodiments of the present invention according to specific situations.

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention.

Referring to FIG. 1, an embodiment of the present invention provides a system 1 for producing silicon wafers, the system 1 for producing silicon wafers may include: Marking unit 10, the marking unit 10 is used to mark marks M with different properties along the direction of the silicon rod axis X on the outer peripheral surface of the single crystal silicon rod R, in the example shown in Figure 1, the mark M includes 7 different The letters a, b, c, d, e, f and g, that is to say, the logo M is discrete and embodies the above-mentioned different properties through different attributes, namely "different letters", but the present invention is not limited thereto, For example, the mark M can also be continuous, such as a continuous groove formed on the outer peripheral surface of the single crystal silicon rod R. For example, different properties can be reflected not only by different attributes, but also by the same attributes but different positions, such as the mark M may include 7 identical letters a with the same property, but these letters a are formed at different positions in the circumferential direction of the monocrystalline silicon rod R, as described in further detail below; Slicing unit 20, the slicing unit 20 is used for cutting the single crystal silicon rod R to cut the single crystal silicon rod R into a plurality of silicon wafers W, wherein the single crystal silicon rod R is exemplarily shown in FIG. The rod R is cut into 7 silicon wafers corresponding to 7 different letters, and the slicing unit 20 can be, for example, a conventional wire cutting device for silicon rods; a processing unit 30, the processing unit 30 is used for performing a processing operation on the plurality of silicon wafers W, wherein during the processing operation, the orientations of the plurality of silicon wafers W relative to each other are changed, and the orientation changes here are arbitrary, For example, the plurality of silicon wafers W are still arranged in a row but the arrangement order changes, for example, the plurality of silicon wafers W rotate relative to each other around the common axis Y, for example, the orientation changes as shown in FIG. 1 , etc.; A determining unit 40, configured to determine according to the identification M that among the plurality of silicon wafers W, the complete silicon wafer WI that has not been broken during the cutting operation and/or during the processing operation is relatively position in relation to each other, or in other words determined in the monocrystalline silicon rod R, Fig. 1 exemplarily shows that no wafers break during the cutting operation, and the wafers marked with the letter f break during the handling operation , and the silicon wafer is filled with hatching to distinguish it from unbroken silicon wafers.

In this way, the complete silicon wafer WI can be placed in the same relative positional relationship as it was before the processing operation or in the single crystal silicon rod R relative to each other by using the marks M with different properties along the direction of the silicon rod axis X. Placement, when the sequence of identification words with a fixed order corresponds to the corresponding positions of the plurality of silicon wafers, such as the location information represented by the identification words and the actual position of the complete silicon wafer WI in the single crystal silicon rod will not appear deviation.

As mentioned above, the properties of the marker M at different positions in the direction of the rod axis X can be different.

Specifically, referring to FIG. 2, the mark M may be a groove G schematically shown by a dot-filled shaded area formed on the outer peripheral surface of the single crystal silicon rod R, and the attribute may be the depth of the groove G d. As shown in FIG. 2 , the depth D of the groove G may gradually increase from left to right.

Also specifically, referring to FIG. 3 , the mark M may be a groove G schematically shown in a dot-filled shaded area formed on the outer peripheral surface of the single crystal silicon rod R, and the property may be that the groove G is in the The width B of the opening at the peripheral surface. As shown in FIG. 2 , the width B of the opening may gradually increase from left to right.

In addition, specifically, referring to FIG. 4, the mark M may be a groove G formed on the peripheral surface of the single crystal silicon rod R, the groove G is defined by two planes P1 and P2, and the attribute may be the two The angle between a plane P1 and a plane P2. For example, the included angle can gradually increase along the direction of the axis X of the silicon rod.

Optionally, the marking unit 10 can form the groove G by machining.

Optionally, the marking unit 10 can form the groove G by laser processing.

During some processing operations, referring to FIG. 1 , the plurality of silicon wafers W may only undergo relative positional changes that move relative to each other along the common axis Y and that the arrangement sequence does not change, but do not rotate relative to each other around the common axis Y. The relative angle changes. For the order of arrangement is constant and no relative angle change occurs, for example, the mechanical arm of the transfer device will follow a fixed path or a consistent path to sequentially cut out the polyhedrons that have just been cut out and are still glued to the resin plate. The silicon wafers are stacked in the silicon wafer storage box. In this case and when no wafers are broken, the positions of the plurality of wafers W relative to each other before the processing operation can be determined even without marking any marks on the outer peripheral surface of the single crystal silicon rod R, but in this case In this case and at least one of the plurality of silicon wafers W is broken during the cutting operation and/or during the processing operation, it cannot be determined without marking a specific mark on the outer peripheral surface of the single crystal silicon rod R The position of the remaining intact wafers relative to each other prior to the processing operation, such as wafer breakage would result in increased spacing between the two wafers located on either side of the broken wafer, but where the plurality of wafers W occurs Changes in the relative position of the movement relative to each other along the common axis Y will also increase the distance between the two wafers, whereby it is not possible to determine for the case where the distance between the two wafers increases Whether it is caused by relative movement or broken silicon wafers. In addition, for two adjacent silicon wafers, it is impossible to determine whether the two silicon wafers are originally adjacent or between the two silicon wafers. There was another silicon chip between them, and the breakage of this other silicon chip caused these two silicon chips to be adjacent, because in the case of the relative movement as described above, it is no longer possible to pass through the gap between the two silicon chips. distance to determine if wafer breakage occurs. More specifically, as shown in Figure 5, it is assumed that the orientations of the upper seven silicon wafers W relative to each other are changed as in the lower six complete silicon wafers WI in the figure, but the reason for this result may be as follows The middle silicon wafer shown on the left side of the figure is broken, and the complete silicon wafer on the right side of the broken silicon wafer moves along the direction indicated by the arrow in the figure, and it may also be the rightmost silicon wafer shown on the right side of the figure Fragmentation occurred but other silicon wafers did not move relative to each other. It can be seen that the position of the six complete silicon wafers WI relative to each other before the processing operation cannot be determined only based on the positional relationship of the six complete silicon wafers WI. .

In order for the determining unit 40 to be able to determine the positions of the complete silicon wafer WI relative to each other before the processing operation, there is no doubt that through the aforementioned embodiments, that is, the different attributes of the marker M at different positions in the direction of the silicon rod axis X are It can be realized, but in an optional embodiment of the present invention, as shown in Figure 6, the mark M can rotate around the silicon rod axis X while extending along the direction of the silicon rod axis X, and the mark M is Properties at different positions in the direction of the silicon rod axis X may be the same, and the different properties are reflected in that the mark M is formed at different positions in the circumferential direction of the single crystal silicon rod R. In this way, the determination unit 40 can determine the positions of the complete silicon wafer WI relative to each other before the processing operation according to the mark M, for example, the marks on the complete silicon wafer WI shown in FIG. Logo M extends in the same way.

Such a mark M is easier to obtain. For example, in the case where the mark M is a groove formed on the outer peripheral surface of the single crystal silicon rod R, the cross section of the groove in a plane perpendicular to the axis X of the silicon rod can be the same , making such grooves easier to machine than grooves that need to have the various properties described above. For example, in the case of machining, the single crystal silicon rod R may be rotated while being longitudinally fed using the same tool.

Referring to FIG. 7 in conjunction with FIG. 1, an embodiment of the present invention also provides a method for producing a silicon wafer W, which may include: S701: marking the outer peripheral surface of the single crystal silicon rod R with a mark M having different properties along the direction of the silicon rod axis X; S702: performing a cutting operation on the single crystal silicon rod R to cut the single crystal silicon rod R into a plurality of silicon wafers W; S703: Perform a processing operation on the plurality of silicon wafers W, wherein the orientations of the plurality of silicon wafers W relative to each other are changed during the processing operation; S704: According to the identifier M, determine the relative positions of the intact silicon wafers WI that are not broken during the cutting operation and/or during the processing operation before the processing operation among the plurality of silicon wafers W.

Referring to Fig. 1, the embodiment of the present invention also provides a single crystal silicon rod R, which is used to obtain a plurality of silicon wafers W through cutting operation, and the outer peripheral surface of the single crystal silicon rod R can be formed with The direction along the axis X of the silicon rods has marks M of different properties, so that when the orientations of the plurality of silicon wafers W relative to each other change during subsequent processing operations, the marks M of the plurality of silicon wafers W can be determined according to the marks M. The positions of intact silicon wafers WI that have not been broken during the cutting operation and/or during the processing operation relative to each other before the processing operation.

It should be noted that: the technical solutions described in the embodiments of the present invention can be combined arbitrarily if there is no conflict.

The above are only preferred embodiments of the present invention, and are not used to limit the implementation scope of the present invention. If the present invention is modified or equivalently replaced without departing from the spirit and scope of the present invention, it shall be covered by the protection of the patent scope of the present invention. in the range.

1: A system for producing silicon wafers 10: Marking unit 20: slice unit 30: Processing unit 40: Determine the unit B: Width D: Depth G: Groove P1: Plane P2: Plane X: silicon rod axis M: Logo R: monocrystalline silicon rod W: Wafer WI: Full Wafer Y: public axis S701-S704: Steps

FIG. 1 is a schematic diagram of a system for producing silicon wafers provided by an embodiment of the present invention; Figure 2 is a front view of a single crystal silicon rod according to the present invention, wherein grooves are shown in a manner formed on top of the silicon rod; 3 is a front view of a single crystal silicon rod according to the present invention, wherein grooves are formed in the middle of the silicon rod; 4 is a cross-sectional view of a single crystal silicon rod according to the present invention; FIG. 5 is a schematic diagram of the orientation change of the silicon wafer; FIG. 6 is a schematic diagram illustrating a change in orientation of a silicon wafer according to an embodiment of the present invention; FIG. 7 is a schematic diagram of a method for producing silicon wafers provided by an embodiment of the present invention.

1: A system for producing silicon wafers

10: Marking unit

20: slice unit

30: Processing unit

40: Determine the unit

X: silicon rod axis

M: Logo

R: monocrystalline silicon rod

W: Wafer

WI: Full Wafer

Y: public axis

Claims (10)

A system for producing silicon wafers, the system comprising: A marking unit, which is used to mark marks with different properties along the direction of the silicon rod axis on the peripheral surface of the single crystal silicon rod; a slicing unit, the slicing unit is used for cutting the single crystal silicon rod to cut the single crystal silicon rod into a plurality of silicon wafers; a processing unit for performing a processing operation on the plurality of wafers, wherein the orientation of the plurality of wafers relative to each other is changed during the processing operation; A determination unit, configured to determine, according to the identification, the positions of intact silicon wafers that have not been broken during the cutting operation and/or during the processing operation relative to each other before the processing operation. The system for producing silicon wafers as claimed in claim 1, wherein the attribute of the mark is different at different positions along the axis of the silicon rod. The system for producing silicon wafers as claimed in claim 2, wherein the mark is a groove formed on the peripheral surface, and the property is the depth of the groove. The system for producing silicon wafers as claimed in claim 2, wherein the mark is a groove formed on the peripheral surface, and the attribute is the width of an opening of the groove at the peripheral surface. The system for producing a silicon wafer as claimed in claim 2, wherein the mark is a groove formed on the peripheral surface, the groove is defined by two planes, and the attribute is the distance between the two planes angle. The system for producing a silicon wafer according to any one of claims 3 to 5, wherein the marking unit forms the groove by machining. The system for producing a silicon wafer according to any one of claims 3 to 5, wherein the marking unit forms the groove by laser processing. The system for producing silicon wafers as claimed in claim 1, wherein the plurality of silicon wafers only undergo relative positional changes that are moved relative to each other along a common axis and are arranged in the same order without relative position changes around the common axis. The relative angle of rotation to each other changes, and at least one of the plurality of silicon wafers breaks during the cutting operation and/or during the processing operation, the marking extends along the direction of the silicon rod axis while extending around the silicon rod axis. When the axis of the silicon rod rotates, the attribute of the marks at different positions along the direction of the axis of the silicon rod is the same, and the different properties are reflected in the fact that the marks are formed at different positions along the circumferential direction of the single crystal silicon rod. A method for producing silicon wafers, the method comprising: Mark the outer peripheral surface of the single crystal silicon rod with markings with different properties along the direction of the silicon rod axis; performing a cutting operation on the single crystal silicon rod to cut the single crystal silicon rod into a plurality of silicon wafers; performing a processing operation on the plurality of wafers, wherein the orientation of the plurality of wafers relative to each other is changed during the processing operation; Based on the identification, the positions of intact silicon wafers of the plurality of wafers that were not broken during the cutting operation and/or during the processing operation relative to each other before the processing operation are determined. The present invention is a single crystal silicon rod, which is used to obtain a plurality of silicon wafers through cutting operations, wherein, the outer peripheral surface of the single crystal silicon rod is formed with marks having different properties along the direction of the silicon rod axis, so that when the orientations of the plurality of silicon wafers relative to each other change during subsequent processing operations, it is possible to determine, according to the identification, which of the plurality of silicon wafers has not been broken during the cutting operation and/or during the processing operation The positions of the full wafers relative to each other prior to the processing operation.

Images