JP3886180B2 - Substrate cradle, substrate extraction / accommodating apparatus and substrate transfer apparatus having the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate transfer apparatus for performing an operation of extracting a substrate such as a silicon wafer or a glass substrate for liquid crystal accommodated in a cassette and transferring it to another cassette, and the substrate. A substrate extraction / accommodation device that is equipped in a transfer device or the like and performs an operation of extracting and accommodating a substrate from a cassette, and a substrate receiving device that the substrate transfer device and the substrate extraction / accommodation device should have for extracting and accommodating the substrate from the cassette. Related to the stand.
[0002]
[Prior art]
Conventionally, this type of substrate transfer apparatus is shown in FIG.
[0003]
As shown in the figure, this conventional substrate transfer apparatus is composed of a pair of first traverse bases 2 having substantially the same shape arranged horizontally in parallel with each other, and parallel to each traverse base 2 and downward. And a second traverse base 3 disposed. The first traverse base 2 and the second traverse base 3 are coupled together and integrated, and this combined body is collectively referred to as a movable base 5. The movable base 5 is driven by a base driving means (not shown) to move forward and backward (indicated by an arrow F), and is appropriately positioned at positions indicated by a two-dot chain line and a solid line in the drawing.
[0004]
As shown in FIG. 7, on the first traverse table 2, the first cassettes 7 each consisting of a self-supporting cassette having a small size and a low height are mounted one by one, and on the second traverse table 3, Two second cassettes 8 are mounted. Specifically, the first traverse base 2 is formed with an opening 2a that opens at one end side in the moving direction, and the first cassette 7 is placed so that the bottom corresponds to the opening 2a. Is done. The second traverse base 3 is formed with two openings 3a that are opened on one end side in the moving direction and two other openings 3b that are opened on the other end side. The second cassette 8 is placed so that the bottom corresponds to the opening 3a on one end side. The opening 3b on the other end side is formed so as to coincide with the opening 2a provided on the first traverse base 2 in the vertical direction.
[0005]
In FIG. 7, reference numeral 2 b indicates a positioning piece that engages with the lower end portion of the first cassette 7 on the first traverse base 2 to position the cassette 7. Although not shown, a similar positioning piece is provided on the second traverse base 3 in order to position the second cassette 8.
[0006]
The movable base 5 and the base driving means (not shown) constitute cassette positioning means for positioning the first cassette 7 and the second cassette 8 at predetermined positions.
[0007]
The first cassette 7 and the second cassette 8 will be described.
[0008]
Each of the first cassette 7 and the second cassette 8 accommodates and holds a plurality of, for example, 26 silicon wafers 10, that is, substrates, aligned at equal intervals so that their main surfaces are substantially parallel to each other. Can do. The first cassette 7 is provided for cleaning the accommodated silicon wafer 10 and is immersed in various processing liquids together with the silicon wafer 10. Therefore, in order to avoid corrosion due to the processing liquid, Teflon, etc. Molded with the required materials.
[0009]
On the other hand, the second cassette 8 is for transporting the silicon wafer 10 that has been subjected to the cleaning process to a subsequent process, and it is not necessary to consider corrosion resistance or the like as in the first cassette 7 and is relatively inexpensive. Molded from common materials.
[0010]
The shapes of the first cassette 7 and the second cassette 8 are as follows.
[0011]
First, as shown in FIG. 7, the first cassette 7 includes a total of four longitudinal substrate support members 7a provided in parallel so as to correspond to two lower portions on both the left and right sides of the silicon wafer 10 to be held. And a pair of flat plate-like side members 7b that are interposed between the end portions of the respective substrate support members 7a and mutually connect the end portions.
[0012]
As shown in FIG. 8, the substrate support member 7a as a whole has a substantially cylindrical shape, and support grooves 7d with which the outer peripheral portion of the silicon wafer 10 is engaged are arranged in parallel at equal pitches in the longitudinal direction. As shown in the figure, the support groove 7d has a substantially trapezoidal cross-sectional shape, for example, and in the present embodiment, 26 ridges are formed. Accordingly, 26 silicon wafers 10 can be held, and each silicon wafer 10 is held in alignment at equal intervals so that its main surfaces are substantially parallel by engaging with the support groove 7d. The
[0013]
On the other hand, as shown in FIGS. 9 and 10, the second cassette 8 is open at the top for loading and unloading the silicon wafer 10, and the outer peripheral portion of each silicon wafer 10 is engaged with the inner wall. Matching support grooves 8a are juxtaposed. The silicon wafers 10 are held in alignment at equal intervals so that their main surfaces are substantially parallel by engaging with the support grooves 8a. An overhanging portion 8 b facing outward is formed at the upper end portion of the second cassette 8. The second cassette 8 also contains 26 silicon wafers 10.
[0014]
An opening 8 c is formed at the bottom of the second cassette 8. As will be described later, the opening 8c is a passage through which a substrate cradle (described later) passes when the silicon wafer 10 is transferred from the first cassette 7 to the second cassette 8.
[0015]
As shown in FIG. 7, each of the first cassette 7 and the second cassette 8 has an opening 2a formed in the first traverse base 2 and the second traverse base 3, respectively. 3a.
[0016]
As shown in FIG. 7, a pair of substrate bases 15 are arranged at predetermined positions corresponding to the openings 2 a, 3 a, 3 b of the first traverse base 2 and the second traverse base 3. The substrate pedestals 15 can be inserted into the two cassettes through the openings 2a, 3a, 3b and the bottom openings of the first cassette 7 and the second cassette 8, and the silicon in the cassettes. Each wafer 10 is received in an aligned state. Specifically, as shown in FIG. 7 and FIG. 11, the substrate pedestal 15 is formed in a substantially rectangular plate shape as a whole, and a single longitudinal protrusion 15a is formed at the center along the longitudinal direction. The two long protrusions 15b are formed on both sides in parallel with each other. The upper end of the central protrusion 15a is flat, and the upper ends of the protrusions 15b on both sides are inclined surfaces that incline downward toward the inside. And in the upper end part of these protrusions 15a and 15b, the receiving grooves 15d and 15e shown in FIG.11 and FIG.12 are provided in parallel 26 pieces over the full length. The outer peripheral portion of the silicon wafer 10 can be engaged with the receiving grooves 15d and 15e, whereby the silicon wafers 10 are supported in alignment so that their main surfaces are substantially parallel to each other.
[0017]
As is apparent from FIG. 12, each of the receiving grooves 15d and 15e has a substantially Y-shaped cross section.
[0018]
Each substrate cradle 15 is supported by a cradle drive means (not shown) and is driven to move up and down, whereby the first cassette 7 and the second cassette 8 are inserted and extracted. The cradle driving means and the substrate cradle 15 constitute a substrate extraction / accommodation apparatus for extracting the silicon wafer 10 from the first cassette 7 and accommodating it in the second cassette 8.
[0019]
As shown in FIG. 7, above the substrate extraction / accommodating device, the silicon wafer 10 is once received from the both substrate receiving bases 15 that have been raised, and the transfer operation is performed in reverse, that is, the transfer means 18 for performing the transfer. Is arranged. As shown in the figure, this delivery means 18 includes two shafts 19 that are rotatably provided, a drive means 20 that relatively rotates each shaft 19, and a suspended state at the tip of each shaft 19. A total of four support shafts 22 that are connected at one end to each free end of each arm member 21 and extend horizontally in parallel with each other, that is, a substrate support member, It has a guide member 24 that supports the other end of each support shaft 22 and smoothly guides it in the direction in which it should operate. As shown in FIG. 13, each support shaft 22 is provided with, for example, 52 strips of support grooves 22 a engaged with the outer peripheral portion of the silicon wafer 10 along the longitudinal direction. One silicon wafer 10 is supported in an aligned state.
[0020]
Next, the operation of the substrate transfer apparatus configured as described above will be described. The following operations are controlled by a control unit including a microcomputer provided in the substrate transfer apparatus.
[0021]
In FIG. 7, the two first cassettes 7 containing the silicon wafers 10 that have been cleaned are placed on the first traverse table 2. Two empty second cassettes 8 are placed on the second traverse table 3. Then, the movable base 5 composed of the first traverse base 2 and the second traverse base 3 is moved forward from the position indicated by the two-dot chain line by the operation of the base drive means (not shown) and reaches the position indicated by the solid line. . As a result, the two first cassettes 7 are positioned at a predetermined position, that is, immediately above each substrate receiving table 15.
[0022]
In this state, the cradle driving means (not shown) is operated, and both the board cradle 15 are raised. Both the board pedestals 15 are inserted through the bottom opening of the first cassette 7 through the openings 3 b and 2 a formed in the second traverse base 3 and the first traverse base 2. Accordingly, each silicon wafer 10 in the first cassette 7 is supported by the substrate cradle 15 and extracted upward. At this time, with respect to the delivery means 18 disposed above, the arm members 21 provided therein are rotated in the direction of mutual separation, and a total of four support shafts 22 for each of the two support shafts 22 to support the silicon wafer 10 are provided. It is in an open state.
[0023]
Both the substrate pedestals 15 continue to rise together with the supported silicon wafers 10, reach the highest rise position, and are stopped. In this state, the silicon wafers 10 are located between the support shafts 22. Subsequently, the delivery means 18 is operated, and the support shafts 22 are closed, that is, chucked. When this chucking operation is completed, both the substrate pedestals 15 are lowered. Thereby, each silicon wafer 10 is engaged with the support groove 22 a (see FIG. 13) formed in each support shaft 22 and is received by each support shaft 22.
[0024]
When the lower substrate holders 15 pass through the first cassette 7, the first traverse table 2 and the second traverse table 3 and reach the lowest position, the movable base 5 is moved backward, as shown in FIG. The position indicated by the two-dot chain line is reached. As a result, the first cassette 7 is detached from immediately above the substrate cradle 15, and instead, the second cassette 8 is positioned directly above the substrate cradle 15.
[0025]
Thereafter, both the board pedestals 15 are raised again. Accordingly, the substrate receiving table 15 passes through the opening 3a of the second traverse table 3 and the second cassette 8 and reaches the highest position. As a result, each silicon wafer 10 supported by each support shaft 22 of the delivery means 18 is slightly lifted by each substrate cradle 15 and delivered to each substrate cradle 15. Then, the support shafts 22 are opened, that is, anti-chucking.
[0026]
When this anti-chucking operation is completed, the both substrate holders 15 are lowered together with the respective silicon wafers 10 that are held. Accordingly, each silicon wafer 10 is stored in the second cassette 8, and only the both substrate receiving bases 15 are further lowered to reach the lowest lowered position.
[0027]
[Problems to be solved by the invention]
The substrate transfer apparatus configured as described above has the following problems.
[0028]
As described above, upper and lower receiving grooves 15d and 15e (see FIGS. 11 and 12) are formed in the substrate pedestal 15, and each silicon wafer 10 has an outer peripheral portion of the receiving grooves 15d and 15e. Is brought into alignment. As is apparent from FIG. 12, the receiving grooves 15d and 15e are formed to be continuous with the tapered portions 15g and 15h, which are introduction portions for aligning the silicon wafer 10, and the tapered portions 15g and 15h. It consists of slit portions 15i and 15j that are positioned substantially at the center of the regular accommodation position. The center of the regular accommodation position is indicated by a dashed line 26.
[0029]
Width w of the slit portions 15i and 15j₁ Is set to be slightly larger than the thickness t of the silicon wafer 10 for the purpose of smooth insertion / removal of the silicon wafer 10 with respect to the slit portion and prevention of sliding. Therefore, as shown by a solid line in FIG. 12, the silicon wafer 10 is engaged with the inner wall surfaces of the slit portions 15i and 15j at the positions a and b, and the inclination θ₁ Is produced. By this inclination, the upper end portion of the silicon wafer 10 is s with respect to the center 26 of the regular accommodation position.₁ Only shake.
[0030]
Specifically, the silicon wafer 10 has a diameter D of 8 (inch) and a thickness t of 0.725 (mm), and the width w of the slit portions 15i and 15j.₁ Is 0.800 (mm), the above deflection s₁ Is about 1.70 (mm). However, this numerical value is the vertical distance vd between the engagement portions a and b of the silicon wafer 10 with respect to the slit portions 15i and 15j.₁ Varies depending on the size of
[0031]
The above deflection₁ In addition to rounding off the value of the third decimal place after the decimal point in the calculation, the numerical value of 1 includes the error due to the outer peripheral portion of the silicon wafer 10 being the tapered portion 10a. is there.
[0032]
As shown by a two-dot chain line in FIG. 12, the silicon wafer 10 has a deflection s in the opposite direction.₁ Also occurs from l, the runout width 2s₁ Is about 3.40 (mm).
[0033]
In the above configuration, the width w of the slit portions 15i and 15j.₁ And the thickness t of the silicon wafer 10 (0.800 mm−0.725 mm = 0.075 mm) is not so large,₁ Is small. Therefore, rattling in a state where the silicon wafers 10 are aligned on the substrate cradle 15 is suppressed, and each silicon wafer 10 is engaged with the support groove 22a (see FIG. 13) of the support shaft 22 provided in the delivery means 18. The vibration of the silicon wafer at the time of joining, that is, the impact is not strong.
[0034]
However, when handling a relatively thin silicon wafer, the above-mentioned runout width 2s.₁ The size of the silicon wafer is considerably large, and the backlash of the silicon wafer on the substrate pedestal 15 is severe, and it is considered that a large impact is applied when the silicon wafer is transferred to the support shaft 22, and particles (which cause contamination of the silicon wafer) There is concern about the occurrence of particles).
[0035]
In addition, the runout width 2s in this way₁ Is large, when each silicon wafer is accommodated in the second cassette 8, the frictional force between the wall surface of the support groove 8a (see FIGS. 9 and 10) formed in the cassette 8 and the silicon wafer increases. Similarly, particles may be generated.
[0036]
The present invention has been made in view of the above points, and provides a substrate cradle in which a swing width of a substrate to be supported is suppressed to be small, a substrate extraction housing device and a substrate transfer device provided with the substrate cradle. Objective.
[0037]
The present invention also provides a substrate cradle, a substrate extraction / accommodating device, and a substrate transfer device that can achieve other effects.
[0038]
[Means for Solving the Problems]
  In order to achieve the above-mentioned object, the substrate base according to the present invention is formed in a substantially rectangular shape as a whole, and has at least one central long protrusion 31a at the center of the long protrusion 31a. Two longitudinal protrusions 31b are formed on both sides in parallel to each other, and a plurality of receiving grooves 31d and 31e are provided at the upper ends of the longitudinal protrusions 31a and 31b, and engage with the receiving grooves 31d and 31e to form a substrate. 10 is a substrate cradle supported by being aligned so that the principal surfaces thereof are substantially parallel to each other, and the receiving grooves 31d and 31e are first tapered portions 31g as introduction portions for aligning the substrates. , 31h formed in the first positioning portion and the first taper portions 31g, 31h of the first positioning portion, the main positioning surface of the substrate having a width slightly larger than the thickness of the substrate. And a second positioning portion formed of slits 31i and 31j for positioning the substrate at a substantially central portion, and a bottom portion of the second positioning portion engaged with an outer peripheral edge of the substrate. Centered That the tapered portion 31m, is provided with a third positioning portion composed of 31n.
  In order to achieve the same object, the substrate extraction / accommodating apparatus according to the present invention is formed in a substantially rectangular shape as a whole, and has at least one longitudinal protrusion 31a at the center and two elongated protrusions on both sides of the longitudinal protrusion 31a. Protrusions 31b are formed in parallel to each other, and a plurality of receiving grooves 31d and 31e are provided at the upper ends of the longitudinal protrusions 31a and 31b. The main surfaces of the substrate 10 are engaged with the receiving grooves 31d and 31e. A substrate cradle that is supported in alignment so as to be substantially parallel and can be inserted through a bottom opening of the cassette into a cassette capable of holding the substrate and can receive the substrate in an aligned state; In the substrate extraction / accommodation apparatus comprising a cradle driving means for supporting the substrate cradle and moving the cassette cradle for insertion and extraction, the receiving grooves 31d and 31e of the substrate cradle include A first positioning portion formed with first tapered portions 31g and 31h as introduction portions for aligning the plates, and the substrate connected to the first tapered portions 31g and 31h of the first positioning portion; A second positioning part having slits 31i and 31j formed along the main surface of the substrate and positioning the substrate at a substantially central part, and the second positioning part. And a third positioning portion including tapered portions 31m and 31n for positioning the center of the substrate by engaging with the outer peripheral edge of the substrate.
  Further, the cassette of the substrate extracting and storing apparatus according to the present invention is provided with a support groove in parallel with which the outer peripheral portion of the substrate is engaged.
  In order to achieve the same object, the substrate transfer apparatus according to the present invention includes cassette positioning means for positioning the first and second cassettes, each of which can hold the substrates in alignment so as to be substantially parallel, at a predetermined position. The whole is formed in a substantially rectangular shape, at least one longitudinal protrusion 31a at the center, and two longitudinal protrusions 31b on both sides of the longitudinal protrusion 31a are formed in parallel to each other to form the longitudinal protrusions 31a, 31b. A plurality of receiving grooves 31d, 31e are provided at the upper end of the substrate 10, and are engaged with the receiving grooves 31d, 31e and supported so that the main surfaces of the substrate 10 are substantially parallel to each other. A substrate holder that is provided at a predetermined position with respect to the two cassettes and that can be inserted through the bottom opening of each of the cassettes and that can receive the substrate in an aligned state; Each cassette In the substrate transfer apparatus comprising a receiving table driving means for moving to insert and withdraw, and a transferring means for transferring the substrate to the substrate receiving table, the receiving grooves 31d, 31e of the substrate receiving table Is connected to the first positioning part formed with the first taper parts 31g and 31h as the introduction part for aligning the substrates, and the first taper parts 31g and 31h of the first positioning part. A second positioning portion having slits 31i and 31j formed along a main surface of the substrate and positioning the substrate at a substantially central portion, and having a width slightly larger than the thickness of the substrate. And a third positioning portion including tapered portions 31m and 31n for positioning the center of the substrate by engaging with the outer peripheral edge of the substrate.
  Further, the delivery means of the substrate transfer apparatus according to the present invention includes a substrate support member that supports the substrates in an aligned state by providing support grooves that engage with the outer peripheral portion of the substrate, and the substrate support. Supporting member driving means for driving the member to engage and disengage the substrate. To do.
  In the substrate transfer apparatus according to the present invention, the thickness of the substrate is t, and the width of the second positioning portion is w. ₂ The vertical distance between the engagement positions of the substrate with respect to the second positioning portion and the third positioning portion is vd. ₂ , And vd is a vertical distance from the engagement position of the substrate to the third positioning portion to the approximate center of the substrate support member. _Three , The opening width of the support groove of the substrate support member is b _Three When b _Three > (W ₂ -T) vd _Three / Vd ₂ + T.
  Further, the first and second cassettes of the substrate transfer apparatus according to the present invention are provided with support grooves that engage with the outer peripheral portion of the substrate.
[0039]
DETAILED DESCRIPTION OF THE INVENTION
Next, the principal part of the substrate transfer apparatus as an embodiment of the present invention will be described. However, the substrate transfer apparatus according to the present invention is configured in the same manner as the substrate transfer apparatus shown in FIGS. 7 to 13 except for the portions described below, and the description of the configuration and operation of the entire apparatus is duplicated. Therefore, it abbreviate | omits and keeps only description of the principal part.
[0040]
In the following description and reference drawings, the same or corresponding components as those of the substrate transfer apparatus shown in FIGS. 7 to 13 are denoted by the same reference numerals.
[0041]
In the substrate transfer apparatus according to the present invention, a substrate holder 31 shown in FIG. 1 is used in place of the substrate holder 15 shown in FIGS.
[0042]
As shown in the figure, the substrate pedestal 31 is also formed in a substantially rectangular plate shape as a whole, with one long protrusion 31a at the center and two long protrusions 31b on both sides in parallel to each other. Has been. The upper end of the central protrusion 31a is flat, and the upper ends of the protrusions 31b on both sides are inclined surfaces that incline downward toward the inside. And the receiving grooves 31d and 31e are juxtaposed along the entire length at the upper ends of these protrusions 31a and 31b. The lower outer peripheral portion of the silicon wafer 10 can engage with the receiving grooves 31d and 31e, and thereby, the silicon wafers 10 are supported in alignment so that their main surfaces are substantially parallel to each other.
[0043]
  FIG.As shown in FIG. 3, the receiving grooves 31d and 31e are substantially Y-shaped in cross section, and taper portions 31g and 31h as first positioning portions that form introduction portions for aligning the silicon wafer 10, respectively. And a slit as a second positioning portion that is formed continuously with the taper portions 31g and 31h and positions the silicon wafer 10 at the substantially central portion of the normal accommodation position.Part31i, 31j. The center of the regular accommodation position is indicated by a one-dot chain line 33.
[0044]
  The slit portions 31i and 31j have a width w for the purpose of smoothly inserting and removing the silicon wafer 10 with respect to the slit portions and preventing sliding.₂Is set slightly larger than the thickness t of the silicon wafer 10The main surface of the silicon wafer 10 is formed.Tapered portions 31m and 31n that engage with the outer peripheral edge of the silicon wafer 10 are provided at the bottoms of the slit portions 31i and 31j. The tapered portions 31m and 31n position the center of the silicon wafer 10 at the center 33 of the regular accommodation position.Third positioning partActs as
[0045]
The silicon wafer 10 is supported by the substrate holder 31 having the above-described configuration as follows.
[0046]
When the silicon wafer 10 enters the receiving grooves 31d and 31e as shown in FIG. 2, the outer peripheral edge of one surface of the silicon wafer 10 contacts one wall surface of the tapered portion 31m as shown in FIG. The silicon wafer 10 slides so as to follow this one wall surface. As a result, as shown in FIG. 4, the outer peripheral edges of both surfaces engage with both wall surfaces of the tapered portion 31m, and the lower portion of the silicon wafer 10 is centered on the center 33. Match. Immediately after this, or simultaneously, as shown in FIG. 5, the silicon wafer 10 is tilted, and its one surface engages with the inner wall surface of the slit 31j at the position h and stops. The inclination angle at this time is θ in FIG.₂ Is shown.
[0047]
Further, in FIG. 5, f and g indicate the locations where the outer peripheral edge of the silicon wafer 10 is engaged with the tapered portion 31 m.
[0048]
Here, the dimensional relationship between the silicon wafer 10 and each part of the apparatus will be described with reference to FIGS.
[0049]
As described above, the widths w of the slit portions 31i and 31j of the receiving grooves 31d and 31e formed in the substrate base 31 are as follows.₂ Is slightly larger than the thickness t of the silicon wafer 10, the silicon wafer 10 has an inclination θ₂ Is produced. By this inclination, the upper end portion of the silicon wafer 10 is s with respect to the center 33 of the normal accommodation position.₂ Only shake. Specifically, the silicon wafer 10 has a diameter D of 8 (inch) and a thickness t of 0.725 (mm), and the width w of the slit portions 31i and 31j.₂ Is 0.800 (mm), this run-out₂ Is about 1.03 (mm). However, this numerical value indicates the engagement points f and g (see FIG. 5) of the silicon wafer 10 with respect to the tapered portion 31m provided at the bottom of the lower slit portion 31i and the engagement portion with respect to the inner wall surface of the upper slit portion 31j. Vertical distance vd with h_Three It changes according to the set value.
[0050]
The above deflection₂ The reason why the numerical value is about is that, in addition to rounding off the value of the third decimal place in the calculation, it includes an error due to the outer peripheral portion of the silicon wafer 10 being the tapered portion 10a.
[0051]
As shown by the two-dot chain line in FIG. 5 and FIG.₂ Can also occur.₂ Is about 2.06 (mm).
[0052]
As described above, in the substrate transfer apparatus, the lower end of the silicon wafer 10 is positioned without being deviated from the center 33 of the normal housing position by the tapered portions 31m and 31n, and the deflection width on the upper end side of the silicon wafer 10 is small. It can be suppressed.
[0053]
Therefore, the play of the silicon wafer 10 on the substrate pedestal 31 is suppressed, and the silicon wafer 10 is engaged with the support groove 22a of the support shaft 22 (see FIG. 13) provided in the delivery means 18 (see FIG. 7). The shaking of the silicon wafer when joining, that is, the impact is small, the generation of particles is prevented, and the environment is kept clean.
[0054]
Further, the runout width 2 s of the silicon wafer 10 is thus obtained.₂ Therefore, when the silicon wafer 10 is accommodated in the second cassette 8 shown in FIGS. 7, 9 and 10, the frictional force between the wall surface of the support groove 8a formed in the cassette 8 and the silicon wafer 10 is also reduced. From this point, the generation of particles is prevented.
[0055]
By the way, in FIG._Three That is, the opening width of the support groove 22a formed in the support shaft 22 provided in the delivery means 18 (see FIG. 7) is set to satisfy the following formula.
[0056]
b_Three > (W₂ -T) vd_Three / Vd₂ + T ・ ・ ・ ▲ 1 ▼
However,
t: thickness of the silicon wafer 10
w₂ : Widths of slit portions (second positioning portions) 31i and 31j of the receiving grooves 31d and 31e formed on the substrate base 31
vd₂ : Vertical distance between the engagement portion h (see FIG. 5) of the silicon wafer 10 with respect to the slit portion 31j and the engagement portions f and g (see FIG. 5) with respect to the tapered portion 31m.
vd_Three : Vertical distance from the engagement position f (see FIG. 5) of the silicon wafer 10 to the slit portion 31m to the center 22b of the support shaft 22 (upper support shaft).
[0057]
That is, in view of reducing the swing width of the silicon wafer 10, the opening width b of the support groove 22 a of the support shaft 22._Three Is set to the minimum necessary value. Thus, the opening width b_Three Is small, the silicon wafer 10 can surely enter the support groove 22a.
[0058]
The support groove 22a has a trapezoidal cross-sectional shape and a width b at the bottom thereof.₂ Is the opening width b_Three Is less than the width b of this bottom₂ May be set to satisfy the following equation.
[0059]
b₂ > (W₂ -T) vd_Three / Vd₂ + T (2)
[0060]
That is, a slight inclination θ on the substrate cradle 31₂ When the support shaft 22 holds the silicon wafers 10 aligned with each other, the peripheral edge of the silicon wafer 10 always has the width b.₂ It is intended to fit within. In this way, it is possible to prevent the outer periphery of the silicon wafer 10 from sliding against the inclined surface portion of the support groove 22a having a trapezoidal cross section, thereby preventing generation of particles.
[0061]
The method of guiding the above formula (1) will be briefly described.
[0062]
First, in FIG. 5, the amount of deviation of the center of the silicon wafer 10 (the amount of deviation from the center 33) is considered at the value of e, that is, at the level of the engagement location h of the silicon wafer 10 with respect to the inner wall surface of the slit portion 31j. This engagement point h is a vertical distance vd from the engagement points f and g of the silicon wafer 10 with respect to the tapered portion 31m.₂ The vertical distance vd from the engagement points f and g_Three The deviation e at the center 22b of the support shaft 22 at the position₂ (Not shown in the figure)
[0063]
e₂ = E · vd_Three / Vd₂
It becomes.
[0064]
The above e is only that the silicon wafer 10 is shifted from the center to one side within the width of the slit portion 31j.
[0065]
e = (w₂ -T) / 2
therefore,
e₂ = (W₂ -T) vd_Three / 2vd₂
It is.
[0066]
The silicon wafer 10 can be tilted to the opposite side with respect to the center 33, and the e₂ Is a deviation amount of the center of the silicon wafer 10, so that ½ of the thickness t is added on both sides (that is, t is added),
(W₂ -T) vd_Three / Vd₂ + T
Get. Since this value is the swing width of the silicon wafer 10 at the level of the support shaft 22 and the center 22b of the support shaft 22, the silicon wafer 10 having this swing width is set to the opening width b of the support groove 22a of the support shaft 22._Three In order to fit within the range, it is necessary to set as in equation (1) above.
[0067]
In the present embodiment, the first positioning portion and the second positioning portion provided on the substrate pedestal 31 and means for positioning the center of the silicon wafer 10 provided at the bottom of the second positioning portion. The taper portions 31g and 31h, the slit portions 31i and 31j, and the taper portions 31m and 31n are not limited to those of the present embodiment, and various forms are possible.
[0068]
However, the taper portion and the slit portion are easy to mold, and if they are combined to form the receiving grooves 31d and 31e having a Y-shaped cross section as in this embodiment, the silicon wafer 10 can be held and released smoothly. Done and useful.
[0069]
【The invention's effect】
As described above, according to the present invention, in the substrate cradle, the introduction portion for aligning the substrate is formed by the first positioning portion, the substrate is positioned at the substantially central portion by the second positioning portion, Further, means for positioning the center of the substrate is provided at the bottom of the second positioning portion.
Due to such a configuration, the lower end of the substrate is positioned without deviating from the center of the regular accommodation position, and the deflection width on the upper end side of the substrate can be suppressed small.
Therefore, the backlash of the substrate on the substrate cradle is suppressed, and the substrate is not shaken when the substrate is engaged with the support groove of the substrate support member provided in the delivery means, that is, the impact is small, and the generation of particles. Is prevented and the environment is kept clean.
In addition, since the swing width of the substrate is small, when the substrate is accommodated in the cassette, the frictional force between the wall surface of the support groove formed in the cassette and the substrate is small, and generation of particles is also prevented from this point.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a state in which a substrate cradle according to the present invention supports a silicon wafer.
2 is a longitudinal sectional view of a part of a substrate cradle as seen from the direction of arrows BB in FIG. 1. FIG.
FIG. 3 is a view for explaining an operation when a silicon wafer is engaged with a receiving groove of the substrate cradle shown in FIGS. 1 and 2;
4 is a view for explaining an operation when a silicon wafer is engaged with a receiving groove of the substrate cradle shown in FIGS. 1 and 2; FIG.
FIG. 5 is a view for explaining an operation when a silicon wafer is engaged with a receiving groove of the substrate cradle shown in FIGS. 1 and 2;
FIG. 6 is a partial view showing a state in which a silicon wafer is engaged with the substrate cradle shown in FIGS. 1 and 2 and a support shaft provided in a delivery means located above the substrate cradle. It is a side view including a cross section.
FIG. 7 is a perspective view of a conventional substrate transfer apparatus.
8 is a plan view showing a longitudinal support member included in a (first) cassette handled by the substrate transfer apparatus shown in FIG. 7 and a part of a silicon wafer engaged therewith. FIG.
9 is a longitudinal sectional view of a (second) cassette handled by the substrate transfer apparatus shown in FIG. 7. FIG.
10 is an AA arrow view of FIG. 9. FIG.
11 is a front view showing a substrate holder and a silicon wafer included in the substrate transfer apparatus shown in FIG. 7; FIG.
12 is a longitudinal sectional view showing a state in which a silicon wafer is engaged with a part of the receiving groove of the substrate cradle shown in FIG.
13 is a side view showing a state in which a silicon wafer is engaged with a support shaft that is a part of the delivery means provided in the substrate transfer apparatus shown in FIG. 7. FIG.
[Explanation of symbols]
2 First traverse stand
3 Second traverse stand
5 Movable base
7 First cassette
7a Long support member (provided by the first cassette 7)
7d Support groove (formed on support member 7a)
8 Second cassette
8a Support groove (formed in the second cassette 8)
10 Silicon wafer (substrate)
18 Delivery means
20 Drive means (with delivery means 18)
22 Support shaft (provided by the delivery means 18) (substrate support member)
22a Support groove formed in the support shaft 22
31 Substrate cradle
31d, 31e (formed on the substrate base 31) receiving grooves
31g, 31h (a part of the receiving grooves 31d, 31e) taper portion (first positioning portion)
31i, 31j (a part of the receiving grooves 31d, 31e) Slit portion (second positioning portion)
31m Tapered portion (provided at the bottom of the slit portions 31i and 31j) (means for positioning the center of the silicon wafer 10 at the center 33 of the regular accommodation position)
33 (in the normal accommodation position where the silicon wafer 10 should be positioned)

Claims (7)

The whole is formed in a substantially rectangular shape, and at least one longitudinal projection 31a is formed at the center, and two longitudinal projections 31b are formed in parallel with each other on both sides of the longitudinal projection 31a, so that the longitudinal projections 31a and 31b A plurality of receiving grooves 31d and 31e are provided at the upper end portion, and are substrate supports that are aligned and supported so that the main surfaces of the substrate 10 are substantially parallel by engaging with the receiving grooves 31d and 31e. ,
The receiving grooves 31d and 31e are
A first positioning part formed with first taper parts 31g and 31h as introduction parts for aligning the substrates;
The first positioning portion is connected to the first taper portions 31g and 31h and has a width slightly larger than the thickness of the substrate, and is formed along the main surface of the substrate so that the substrate is substantially at the center. A second positioning portion comprising slit portions 31i, 31j to be positioned;
3. A substrate pedestal comprising a third positioning portion comprising tapered portions 31m and 31n for positioning the center of the substrate by engaging the outer peripheral edge of the substrate at the bottom of the second positioning portion . The whole is formed in a substantially rectangular shape, and at least one longitudinal projection 31a is formed at the center, and two longitudinal projections 31b are formed in parallel with each other on both sides of the longitudinal projection 31a, so that the longitudinal projections 31a and 31b A plurality of receiving grooves 31d and 31e are provided on the upper end portion, and are engaged with and supported by the receiving grooves 31d and 31e so that the main surfaces of the substrate 10 are substantially parallel to each other, thereby holding the substrate. eggplant and substrate pedestal capable of kicking receive maintains the alignment of the substrate with be inserted through the bottom opening of the cassette relative to the cassette, inserted to said cassette carrying the substrate pedestal, withdrawal In the substrate extraction and storage device provided with the cradle drive means to move as much as possible,
The receiving grooves 31d and 31e of the substrate holder are
A first positioning part formed with first taper parts 31g and 31h as introduction parts for aligning the substrates;
The first positioning portion is connected to the first taper portions 31g and 31h and has a width slightly larger than the thickness of the substrate, and is formed along the main surface of the substrate so that the substrate is substantially at the center. A second positioning portion comprising slit portions 31i, 31j to be positioned;
3. A substrate extraction / accommodating apparatus comprising: a third positioning portion comprising tapered portions 31m and 31n for engaging the outer peripheral edge of the substrate and positioning the center of the substrate at the bottom of the second positioning portion. . 3. The substrate extraction / accommodation apparatus according to claim 2 , wherein the cassette is provided with support grooves that engage with the outer peripheral portion of the substrate. Cassette positioning means for positioning the first and second cassettes, each of which can hold the substrates in alignment so as to be substantially parallel, at a predetermined position;
The whole is formed in a substantially rectangular shape, and at least one longitudinal projection 31a is formed at the center, and two longitudinal projections 31b are formed in parallel with each other on both sides of the longitudinal projection 31a, so that the longitudinal projections 31a and 31b A plurality of receiving grooves 31d and 31e are provided at the upper end portion, and are engaged with the receiving grooves 31d and 31e and supported so that the main surfaces of the substrate 10 are substantially parallel to each other. A substrate holder that is provided at a predetermined position with respect to the cassette of the cassette and can be inserted through the bottom opening of each of the cassettes and can receive the substrate in an aligned state;
In a substrate transfer apparatus comprising: a receiving table driving means that carries the substrate receiving table and moves it to insert and withdraw each cassette; and a transferring means that transfers the substrate to and from the substrate receiving table.
The receiving grooves 31d and 31e of the substrate holder are
A first positioning part formed with first taper parts 31g and 31h as introduction parts for aligning the substrates;
The first positioning portion is connected to the first taper portions 31g and 31h and has a width slightly larger than the thickness of the substrate, and is formed along the main surface of the substrate so that the substrate is substantially at the center. slits 31i for position-decided fit, and a second positioning portion consisting 31j,
3. A substrate transfer apparatus comprising: a third positioning portion comprising tapered portions 31m and 31n for engaging the outer peripheral edge of the substrate to position the center of the substrate at the bottom of the second positioning portion . The delivery means includes a substrate support member for supporting the substrates in an aligned state by supporting grooves that are engaged with the outer peripheral portion of the substrate, and engaging the substrate support member with the substrate and the substrate support member. 6. The substrate transfer apparatus according to claim 5, further comprising support member driving means for driving to release. The thickness of the substrate is t, the width of the second positioning portion is w ₂ , the vertical distance between the engagement positions of the substrate with respect to the second positioning portion and the third positioning portion is vd ₂ , and the third When the vertical distance from the engagement position of the substrate to the positioning portion of the substrate to the approximate center of the substrate support member is vd ₃ and the opening width of the support groove of the substrate support member is b ₃ , b ₃ > (w ₂ − 6. The substrate transfer apparatus according to claim 5, wherein t) is vd ₃ / vd ₂ + t. The substrate transfer apparatus according to any one of claims 4 to 6 , wherein the first and second cassettes are provided with support grooves that engage with an outer peripheral portion of the substrate. .

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