JP5929683B2 - Semiconductor substrate separation / transfer method and semiconductor substrate separation / transfer apparatus - Google Patents

Description

  The present invention relates to a separation transfer method and a separation transfer device for semiconductor substrates, in which a plurality of semiconductor substrates stacked and stacked are separated into a single piece and stored separately in a carrier.

  In a semiconductor process, a semiconductor substrate, such as a silicon wafer, is usually placed in a storage tool (eg, carrier, quartz boat, etc.) made of polypropylene, Teflon (registered trademark), quartz, SiC, etc. Processed, moved between each process, or stored for a predetermined period. Further, there is a case where an operation of transferring a plurality of silicon wafers stacked up and down after performing necessary processing to a wafer storage device such as a carrier is often performed.

  As a silicon wafer after processing, for example, there is a wafer immediately after being cut out from a silicon ingot, and it is in a state in which unpolished wafers are directly stacked (stacked and stacked, wafer group). Accordingly, since the silicon wafer cannot be processed as it is, it is necessary to separate the directly stacked wafers into a single piece by the wafer separating / transferring apparatus and store them at a predetermined pitch in the carrier.

  Here, when the wafers are separated from the directly stacked wafer group, the wafers stacked one above the other may be stuck to each other. It was difficult to store.

Therefore, in Japanese Patent Application Laid-Open No. 2010-165828 (Patent Document 1), at least the uppermost wafer is attracted to the uppermost wafer while a plurality of wafers are adsorbed in the liquid while the ultrasonic wave is applied to the uppermost wafer. A method of separating a wafer while sliding in an in-plane direction is disclosed. Japanese Patent Laying-Open No. 2011-129852 (Patent Document 2) discloses a method of separating wafers one by one by jetting a water flow containing bubbles in a liquid.
However, even with these methods, separation of the wafer is difficult or a complicated mechanism may be obtained.

JP 2010-165828 A JP 2011-129652 A

  The present invention has been made in view of the above circumstances, and a semiconductor substrate separation / transfer method and a semiconductor substrate separation / transfer apparatus capable of easily separating semiconductor substrates one by one from a group of semiconductor substrates by a simple method. The purpose is to provide.

In order to achieve the above object, the present invention provides the following semiconductor substrate separation / transfer method and semiconductor substrate separation / transfer apparatus.
[1] An adsorbing tool is adsorbed to the uppermost semiconductor substrate of the semiconductor substrate group in which a plurality of semiconductor substrates are stacked and stacked, and the semiconductor substrate group is set to the resonance frequency of the semiconductor substrate group or a frequency in the vicinity thereof. The semiconductor device separated from the semiconductor substrate group is separated from the semiconductor substrate group by moving the suction tool while oscillating the substrate, and the semiconductor substrate broken from the semiconductor substrate group is damaged by the vibration. A method for separating and transferring a semiconductor substrate, wherein the semiconductor substrate is divided into a semiconductor substrate that is not damaged, and the semiconductor substrate that is not damaged is transferred to a carrier.
[2] The method for separating and transferring a semiconductor substrate according to [1], wherein the semiconductor substrate is a silicon wafer cut out from a silicon ingot.
[3] The method for separating and transferring a semiconductor substrate according to [1] or [2], wherein the frequency for exciting the semiconductor substrate group is 750 to 950 kHz.
[4] The semiconductor substrate group is vibrated by a vibrator comprising a high-frequency oscillator and a vibrator attached to a mounting table on which the semiconductor substrate group is placed [1] to [3] A method for separating and transferring a semiconductor substrate according to any one of the above.
[5] The method for separating and transferring a semiconductor substrate according to [4], wherein the output of the vibrator is 600 to 900 W.
[ 6 ] A mounting table for mounting a semiconductor substrate group composed of a plurality of stacked semiconductor substrates, an adsorbing tool that adsorbs to the uppermost semiconductor substrate of the semiconductor substrate group, and a moving mechanism that moves the adsorbing tool And determining whether or not the semiconductor substrate is damaged based on the image processing of the monitor image of the semiconductor substrate, and a vibrator comprising a high-frequency oscillator and a vibrator attached to the mounting table and vibrating the semiconductor substrate group. A damage determination unit , adsorbing an adsorber to the uppermost semiconductor substrate of the semiconductor substrate group, and vibrating the semiconductor substrate group at a resonance frequency of the semiconductor substrate group or a frequency in the vicinity thereof, a single semiconductor substrate adsorbed by moving the suction device is separated from the semiconductor substrate group, a semiconductor group damaged by the vibration from the determination result of the failure determining unit for the semiconductor substrate separated from the semiconductor substrate group And it is divided into and the semiconductor substrate is not damaged, for the semiconductor substrate separating the transfer device, characterized in that for transferring the semiconductor substrate to a carrier that does not damage.
[7] the suction device is intended to be adsorbed on the semiconductor substrate by utilizing a negative pressure generated by the Bernoulli principle, or characterized in that adsorbed on the semiconductor substrate by vacuum suction of [6] Separation and transfer equipment for semiconductor substrates.

  According to the present invention, since the semiconductor substrate group resonates by vibrating the semiconductor substrate group at the resonance frequency of the semiconductor substrate group or a frequency in the vicinity thereof, the degree of sticking between the semiconductor substrates is reduced, and the semiconductor A semiconductor substrate can be easily separated from the substrate group in units of one sheet and stored in a carrier. Further, in the present invention, when a semiconductor substrate that has chipping (chip or crack) and is unsuitable as a product is included, the chip resonates at the time of vibration and breaks down at the chipping portion, so that the semiconductor substrate without chipping can be easily obtained. Since it becomes possible to distinguish, the semiconductor substrate can be separated and transferred as well as destructive inspection of the substrate.

It is a cross-sectional schematic diagram which shows the structural example of the separation transfer apparatus for semiconductor substrates which concerns on this invention. It is a top view which shows the structure of the mounting base of the separation transfer apparatus of FIG. It is the schematic which shows the structural example of the high frequency oscillator used for the separation transfer apparatus of FIG. It is process drawing of the separation transfer method of the semiconductor substrate concerning the present invention, (a) is the figure which adsorbed the adsorption tool to the semiconductor substrate, (b) is the figure which separated one semiconductor substrate while vibrating, (C) is a figure which accommodates a semiconductor substrate in a carrier.

Hereinafter, a configuration of an embodiment of a semiconductor substrate separation / transfer method and a semiconductor substrate separation / transfer apparatus according to the present invention will be described.
FIG. 1 shows a configuration example of a semiconductor substrate separation / transfer apparatus according to the present invention.
As shown in FIG. 1, a semiconductor substrate separating / transferring device 1 (hereinafter, separating / transferring device 1) includes a mounting table 3 on which a semiconductor substrate group 2 composed of a plurality of semiconductor substrates 2p stacked on each other, An adsorbing tool 4 that adsorbs to the uppermost semiconductor substrate 2p of the semiconductor substrate group 2, an arm-shaped moving mechanism 5 that moves the adsorbing tool 4, and the mounting table 3 are attached to the semiconductor substrate group 2 as a semiconductor. A vibrator 6 that vibrates at a resonance frequency of the substrate group 2 or a frequency in the vicinity thereof, separates the semiconductor substrates 2p one by one from the semiconductor substrate group 2, and transports the separated semiconductor substrates 2p to the carrier 8, It is to be stored. In FIG. 1, the main part is shown.

  Here, the semiconductor substrate group 2 includes a plurality of semiconductor substrates 2p having the same shape and the same dimensions, for example, a plurality of silicon wafers. Particularly preferably, the semiconductor substrate 2p constituting the semiconductor substrate group 2 is a silicon wafer immediately after being cut out from the silicon ingot. At this time, the semiconductor substrate 2p is in a wet state, and the substrates are bonded to each other by the surface tension of moisture. In this state, the semiconductor substrate group 2 is a single structure.

  The thickness t of the semiconductor substrate 2p is, for example, 100 to 300 μm when the semiconductor substrate 2p is a 200 mm diameter or pseudo-square silicon wafer.

  The mounting table 3 is mounted with a semiconductor substrate group 2 in which a plurality of semiconductor substrates 2p are superposed in a direction perpendicular to the plate surface, and a base plate 3a that supports the semiconductor substrate group 2 and a standing plate 3a. The semiconductor substrate group 2 includes an enclosure 3b that surrounds the four sides of the semiconductor substrate 2p in the plate surface direction (horizontal direction) and restricts the movement of the semiconductor substrate group 2 in the horizontal direction. Both the base plate 3a and the enclosure 3b are made of wood, polypropylene, Teflon (registered trademark), or the like.

  Further, as shown in FIG. 2, the enclosure 3b is fixed to the base plate 3a so that the three-way enclosure 3b1 surrounding the three horizontal sides of the semiconductor substrate group 2 and one of the three-side enclosure 3b1 that are open can be removed. It consists of the blocking part 3b2 to block.

  When mounting the semiconductor substrate 2p on the mounting table 3, first, a plurality of semiconductor substrates 2p are mounted on the base plate 3a from the open side of the three-way enclosure 3b1 while the end portions thereof are in contact with the three-way enclosure 3b1. Then, the opening of the three-way enclosure 3b1 is sealed with the blocking part 3b2. Thereby, the semiconductor substrate group 2 is mounted on the mounting table 3 in a state where the end surfaces of the semiconductor substrates 2p are aligned and overlapped.

  For example, when the semiconductor substrate 2p is a silicon wafer, the number of the semiconductor substrates 2p placed on the mounting table 3 preferably corresponds to the number of the carriers 8 that store the silicon wafer, and is about 25 to 150. is there.

  The adsorbing tool 4 is a general-purpose non-contact that adsorbs to a semiconductor substrate using negative pressure generated by Bernoulli's principle as described in, for example, Japanese Patent Application Laid-Open Nos. 2002-368065 and 2011-245588. An adsorbing tool is preferred. Thereby, the semiconductor substrate 2p can be levitated and held so as to be suspended in a non-contact manner, and damage to the semiconductor substrate 2p due to contact with the semiconductor substrate 2p can be prevented. Alternatively, the suction tool 4 may be a vacuum suction pad that is sucked onto a semiconductor substrate by vacuum suction as described in, for example, Japanese Patent Application Laid-Open No. 2011-29388.

  The moving mechanism 5 is a transfer arm having the suction tool 4 at the tip of the arm and having a drive unit (not shown) at the arm base. It is possible to move the moving mechanism 5 which is a transfer arm in the horizontal direction and the vertical direction by the driving unit, and the suction tool 4 at the tip of the transfer arm is moved in the horizontal direction so that An operation for controlling the operation to be arranged above and away from the upper part, and to move the suction tool 4 in the vertical direction so as to approach or move away from the uppermost part of the semiconductor substrate group 2 on the mounting table 3. By performing the control, the suction operation of the suction tool 4 to the semiconductor substrate 2p and the separation and transfer operation of the semiconductor substrate 2p can be performed. In FIG. 1, a moving mechanism for storing the semiconductor substrate 2p separated from the semiconductor substrate group 2 in a carrier 8 described later is omitted, but a conventionally known mechanism may be employed.

  The vibrator 6 includes a high-frequency oscillator and a vibrator attached to the bottom of the mounting table 3, that is, the surface of the base plate 3a opposite to the mounting surface of the semiconductor substrate group 2. Specifically, the vibrator 6 has a configuration in which piezoelectric ceramics serving as a vibrator is inserted between electrodes to which a high-frequency oscillator is connected, and the piezoelectric ceramic (vibrator) is fixed to the base plate 3a. Yes.

  In driving the vibrator 6, first, a high-frequency pulse voltage or an AC voltage is applied between the electrodes from the high-frequency oscillator, and the piezoelectric ceramic vibrates by repeatedly expanding and contracting as a vibrator corresponding to the applied voltage. Is transmitted to the semiconductor substrate group 2 via the mounting table 3, and the semiconductor substrate group 2 is vibrated.

  This piezoelectric ceramic is a polycrystalline ceramic obtained by baking a powder of high-purity titanium oxide, barium oxide or the like at a high temperature, and the shape thereof is a circular vibrator having a diameter of 10 to 70 mmφ (see FIG. 3). 3 (a)) or a donut-type resonator (FIG. 3 (b)). In FIG. 3, the high frequency oscillator is omitted.

  Next, as a method for separating and transferring a semiconductor substrate according to the present invention, a processing procedure when the separating and transferring apparatus 1 having the above structure is used will be described with reference to FIG. The semiconductor substrate 2p is a silicon wafer immediately after being cut out from the silicon ingot.

First, in the separation / transfer apparatus 1, a plurality of semiconductor substrates 2p are placed on the base plate 3a of the mounting table 3 with their respective ends abutting against the three-way enclosure 3b1, and the opening of the three-way enclosure 3b1 is sealed. Sealed by the part 3b2 and arranged as the semiconductor substrate group 2.
Next, the suction tool 4 is moved by the moving mechanism 5, the suction tool 4 is brought close to the uppermost semiconductor substrate 2 p of the semiconductor substrate group 2, and the suction tool 4 is sucked to the semiconductor substrate 2 p ( Up to this point, FIG.

Next, the vibrator 6 is driven to vibrate the semiconductor substrate group 2 at the resonance frequency of the semiconductor substrate group 2 or a frequency in the vicinity thereof. At this time, the frequency for exciting the semiconductor substrate group 2 is preferably 750 to 950 kHz. If the frequency of exciting the semiconductor substrate group 2 is out of the range, the semiconductor substrate group 2 does not resonate and does not vibrate, so that the degree of sticking between the semiconductor substrates 2p cannot be relaxed, and one semiconductor substrate 2p is formed. It may be difficult to separate them one by one.
Moreover, it is preferable that the output of the vibrator 6 is 600-900W. If the output of the vibrator 6 is less than 600 W, it may be insufficient to eliminate the sticking between the semiconductor substrates 2p. If it exceeds 900 W, even the normal semiconductor substrate 2p without chipping will be destroyed. There is a fear.
By the above vibration, sticking between the semiconductor substrates 2p is eliminated, and the semiconductor substrate 2p is easily separated from the semiconductor substrate group 2 by one by moving the suction tool 4 in the vertical direction by the moving mechanism 5. (FIG. 4 (b) so far).

Further, in the semiconductor substrate group 2 made of the silicon wafer (semiconductor substrate 2p) immediately after being cut out from the silicon ingot, the semiconductor substrate 2p that has chipping (chip or crack) and is unsuitable as a product is mixed. The semiconductor substrate 2p that has chipping (chip or crack) at the time of vibration as described above and is unsuitable as a product can be easily distinguished from a semiconductor substrate without chipping due to the resonance of the semiconductor substrate group 2 due to the breakdown at the chipping portion. Become. Therefore, the semiconductor substrate 2p separated from the semiconductor substrate group 2 as described above is divided into the semiconductor substrate 2p damaged by the vibration and the semiconductor substrate 2p that is not damaged, and the semiconductor substrate 2p that is not damaged is transferred to a carrier to be described later. Good. Whether the semiconductor substrate 2p is damaged or not can be identified by monitor observation or by damage determination based on image processing of the monitor image.
As described above, according to the present invention, the semiconductor substrate 2p can be separated and transferred, and can also serve as a substrate destructive inspection.

Next, the separated single semiconductor substrate 2p is transferred to the carrier 8 (FIG. 4C).
Here, the carrier 8 is a jig for storing the semiconductor substrates 2p one by one in order to wet-clean the semiconductor substrate 2p, for example, PFA (tetrafluoroethylene / perfluoroalkoxyethylene copolymer), PTFE ( This is a rectangular box-shaped container made of a fluororesin material having excellent chemical resistance (such as polytetrafluoroethylene) and having an open top composed of a bottom plate and a side plate, and the inner surfaces of one side plates 8a and 8a facing each other. Each of the plurality of substrate holding grooves (or shelves) for holding both ends of the semiconductor substrate 2p is provided in a direction perpendicular to the substrate surface of the semiconductor substrate 2p, that is, in a parallel arrangement direction of the semiconductor substrates 2p. .

  When the semiconductor substrate 2p is transferred to the carrier 8, for example, as shown in FIG. 4C, the main surface is arranged in the parallel arrangement direction in the carrier 8 with respect to the carrier 8 arranged so that the upper part becomes an opening. The semiconductor substrate 2p in a vertically standing state is lowered from above the carrier 8 toward the carrier 8, and both ends of the semiconductor substrate 2p are inserted into opposing substrate holding grooves provided on both side plates 8a of the carrier 8. Like that. Alternatively, the carrier 8 is placed so that its opening portion faces sideways, and a pair of opposing substrate holding grooves (shelves) provided on the side plates 8a and 8a are arranged in parallel to each other in the vertical direction. The semiconductor substrate 2p is slid from the side of the carrier 8 toward the carrier 8 with the main surface thereof facing upward, and both ends of the semiconductor substrate 2p are opposed substrates provided on both side plates 8a of the carrier 8. You may make it insert in a holding groove. Thus, the plurality of semiconductor substrates 2p are supported one by one by the substrate holding grooves and stored in a state of being arranged in parallel. Thereafter, using the carrier 8 in which the semiconductor substrate 2p is housed in this way, a wet process from etching, texture formation, cleaning, rinsing, and draining to remove slice damage is performed according to a conventional method.

  As described above, according to the present invention, the semiconductor substrate group 2 resonates by vibrating the semiconductor substrate group 2 at the resonance frequency of the semiconductor substrate group 2 or a frequency in the vicinity thereof. The degree of sticking is relaxed, and the semiconductor substrate 2 p can be easily separated from the semiconductor substrate group 2 in units of one sheet and stored in the carrier 8. In the present invention, since the semiconductor substrate 2p having chipping and unsuitable as a product is broken at the chipping portion due to the resonance during the vibration, it can be easily distinguished from the semiconductor substrate 2p without chipping. In addition to the separation and transfer of the substrate, it can also serve as a destructive inspection of the substrate. That is, according to the present invention, it is possible to transfer practical semiconductor substrates 2p having high strength one by one.

  The semiconductor substrate separation / transfer method and semiconductor substrate separation / transfer apparatus according to the present invention can be applied to, for example, a silicon solar cell production line. Specifically, the present invention can be used in a substrate receiving process in a solar cell production line. In a production line for solar cells, silicon wafers obtained by slicing from a silicon ingot are accepted in a stacked state. Usually, the first step in the production line is texture formation. Here, the texture forming process is a process of forming fine irregularities on the surface of the silicon substrate and lowering the reflectivity of the substrate. Generally, wet etching is often used because of its high mass productivity. It is necessary to transfer the processed silicon wafer to a carrier for processing. At that time, if the present invention is applied, silicon wafers can be transferred one by one without sticking, and a silicon wafer having high strength without chipping can be sent to the next process.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, you may delete some components from all the components shown by embodiment mentioned above.

For example, in the above-described embodiment, the case where the semiconductor substrate 2p is accommodated in the carrier 8 has been described. However, the present invention is not limited to this and can be used when the semiconductor substrate 2p is simply separated into a single piece.
In the above-described embodiment, the case where the semiconductor substrate 2p is separated with the semiconductor substrate group 2 mounted on the mounting table 3 in the atmosphere has been described. However, the present invention is not limited thereto, and a surfactant is added. In a state where the semiconductor substrate group 2 is mounted on the mounting table 3 in a liquid such as pure water, the semiconductor substrates 2p may be separated one by one by vibrating as described above.

1 Separation / Transfer Equipment for Semiconductor Substrate (Separation / Transfer Equipment)
2 Semiconductor substrate group 2p Semiconductor substrate 3 Mounting table 3a Base plate 3b Enclosure 3b1 Three-way enclosure 3b2 Sealing portion 4 Adsorber 5 Moving mechanism 6 Exciter 8 Carrier 8a Side plate

Claims (7)

A suction tool is attracted to the uppermost semiconductor substrate of the semiconductor substrate group in which a plurality of semiconductor substrates are stacked and stacked, and the semiconductor substrate group is vibrated at a resonance frequency of the semiconductor substrate group or a frequency in the vicinity thereof. However, the semiconductor substrate separated from the semiconductor substrate group is separated from the semiconductor substrate group by moving the suction tool and the semiconductor substrate that is damaged by the vibration and the semiconductor substrate that is not damaged A method for separating and transferring a semiconductor substrate, wherein a semiconductor substrate that is not damaged is transferred to a carrier.   2. The method for separating and transferring a semiconductor substrate according to claim 1, wherein the semiconductor substrate is a silicon wafer cut out from a silicon ingot.   3. The method for separating and transferring a semiconductor substrate according to claim 1, wherein a frequency for exciting the semiconductor substrate group is 750 to 950 kHz.   4. The semiconductor substrate group is vibrated by a vibrator comprising a high-frequency oscillator and a vibrator attached to a mounting table on which the semiconductor substrate group is placed. 2. A method for separating and transferring a semiconductor substrate according to 1.   The method for separating and transferring a semiconductor substrate according to claim 4, wherein an output of the vibrator is 600 to 900 W. A mounting table for mounting a semiconductor substrate group composed of a plurality of stacked semiconductor substrates, an adsorbing tool that adsorbs to the uppermost semiconductor substrate of the semiconductor substrate group, a moving mechanism that moves the adsorbing tool, A vibration exciter comprising a high-frequency oscillator and a vibrator that vibrates the semiconductor substrate group attached to the mounting table, and a damage determination unit that determines whether or not the semiconductor substrate is damaged based on image processing of a monitor image of the semiconductor substrate The adsorbing tool is adsorbed on the uppermost semiconductor substrate of the semiconductor substrate group, and the adsorbing tool is vibrated while vibrating the semiconductor substrate group at a resonance frequency of the semiconductor substrate group or a frequency in the vicinity thereof. the moved to separate one semiconductor substrate which is adsorbed from the semiconductor substrate group, breakage from the determination result of the failure determining unit for the semiconductor substrate separated from the semiconductor substrate group and the semiconductor substrate was damaged by vibration the pressing Not divided into a semiconductor substrate, a semiconductor substrate separating the transfer device, characterized in that for transferring the semiconductor substrate to a carrier that does not damage. 7. The semiconductor substrate according to claim 6 , wherein the adsorbing tool is adsorbed on the semiconductor substrate using a negative pressure generated by Bernoulli's principle, or adsorbed on the semiconductor substrate by vacuum suction. Separation transfer equipment.

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