DE102017105306A1 - Holding device for holding a plurality of wafers - Google Patents

Abstract

The invention relates to a support for a holding device for holding a plurality of wafers, comprising a support surface for a wafer and a securing device for releasably securing to the holding device. Furthermore, the invention relates to a holding device for holding a plurality of wafers, comprising two end holders and at least one web extending between the end holders and a plurality of supports each having at least one support surface for a wafer.

Description

The invention relates to a support for a holding device for holding a plurality of wafers, comprising a support surface for a wafer. Furthermore, the invention relates to a holding device for holding a plurality of wafers, comprising two end holders and at least one web extending between the end holders and a plurality of supports each having at least one support surface for a wafer.

As a wafer, a semiconductor wafer is called. A semiconductor wafer may be round or square and have a thickness of about one millimeter. As a rule, a wafer consists of monocrystalline silicon, although materials such as silicon carbide are also conceivable.

Typically, the diameters of silicon wafers are 150 mm to 450 mm.

Machining processes require wafer holding fixtures, also referred to as wafer boats. The wafer boats can be oriented vertically or horizontally depending on the application. The machining processes may include high temperature processes for coating, diffusion and / or oxidation. Also, semiconductor and / or solar processes, e.g. Nitride or poly-oxidation processes require the use of fixtures.

In high-temperature processes, temperatures of over 1,000 ° C occur. The holding devices must withstand these high temperatures.

Wafer boats are known in which several pads are attached to a bridge. The pads include bearing surfaces on which a wafer is placed or held and held. The pads are sort of compartments for the wafers.

In conventional wafer boats, the pads are firmly connected to the web, for example, welded. If one edition or several copies are damaged, the entire wafer boat must always be replaced. This is associated with high costs.

Since the requirements usually consist, for example, of fragile materials such as silicon carbide or quartz, damage occurs comparatively frequently. For example, a pad may break when the wafer boat is laid down.

Even during operation, the pads wear out more than other components of the wafer boat. The service life of a wafer boat is limited by the requirements.

It is therefore an object of the invention to provide a support for a holding device and a holding device for holding a plurality of wafers, which extend the service life of the holding device in a simple and cost-effective manner.

The solution of this object is achieved by the subject matters of the independent claims.

According to the invention, the support comprises a securing device for releasably securing to the holding device. Preferably, the securing device is releasably secured or attachable to a web of the holding device.

If the overlay is damaged, it can therefore be replaced without having to replace the complete holding device. Due to the modular structure, the service life of the holding device can thus be significantly extended, thereby saving costs.

The support is preferably made of silicon or comprises silicon. Silicon has several advantages. For example, silicon is relatively stable, so that a safe transport and maintenance are possible. Furthermore, silicon is heat resistant even at high temperatures. In addition, no impurities occur during processing, so that the support must be replaced less often.

Further developments of the invention can be found in the dependent claims, the description and the accompanying drawings.

According to one embodiment, the securing device comprises a hooking, clamping, plugging, latching and / or screwing device.

The support can be easily releasably attached to the fixture. In particular, the assembly or disassembly of the support can be done without tools. A quick exchange is guaranteed.

According to a further embodiment, the securing device has a securing nose, which in particular can be brought into engagement with a securing receptacle of a web of the holding device. Preferably, the securing lug can be latched or pinned to the securing receptacle. As a result, unintentional release of the support can be prevented.

Alternatively, or in addition to a latching or pinning the pad can for example be clamped on the web.

According to a further embodiment, the securing lug extends in the plane of the support surface. For example, the support surface may have a recess to form the backup nose. In particular, at least a part of the web can then be received in the recess.

According to a further embodiment, the securing nose extends from the plane of the support surface. In particular, this may result in an L-shaped structure of the support.

The securing nose may be e.g. extend at right angles to the support surface. In particular, the securing nose may be a bent region of the supporting surface. Also, the securing lug may e.g. be produced by machining, in particular milling, cutting or lasers.

According to a further embodiment, the support surface is plate-shaped, in particular sickle-shaped or annular, formed. By a plate-shaped design of the support surface, a wafer can just rest on the support surface. A sickle shape prevents the wafer from slipping sideways out of the support.

The invention also relates to a holding device for holding a plurality of wafers with two end holders.

The Endhalterungen may be plate-shaped, in particular as rectangular, round or annular plates.

The holding device comprises at least one web extending between the end holders. Preferably, a plurality of webs are provided. For example, two, three, four, five or more webs may be provided. The pads can be held securely on the webs in this way.

A web may have a rectangular, in particular square, cross-section. Alternatively, a web can also have a round, in particular circular or elliptical, cross-section.

In particular, at least one end region, preferably both end regions, of the web can be detachably connected or connected to the adjacent end holder. The webs or Endhalterungen can thus be replaced if necessary.

For example, at least one end region, preferably both end regions, of the web can be connected or connectable by means of a screw connection to the adjacent end holder. The same method of attachment can be used on both end areas of a bar. Alternatively, however, it is also possible to have a screw connection only at one end region of the web and an alternative attachment, for example at the other end region of the web. an adhesive, plug and / or solder joint to provide. Preferably, however, both end portions of all webs are connected via screw to the end brackets or connectable, resulting in a modular structure.

Preferably, the screw connection may comprise at least one screw, e.g. of silicon. Screws are comparatively inexpensive to produce. As an alternative to a screw, for example, the end bracket may have a pin with an external thread, which can be connected to an internal thread of the web. The reverse case is also conceivable. Thus, the web can have an external thread which can be turned into an internal thread of an end holder, for example into a sleeve.

In particular, exactly one screw can be provided for each end region of a web. This is sufficient for a secure hold. In principle, however, several, e.g. two, screws per end area may be provided.

The screw can be designed as a separate component and thus easily replaced. However, it is also possible that the screw, for example, as a threaded pin, is firmly connected to the end bracket.

The end support may have a cone-shaped receptacle for a screw head. The receptacle can be designed in particular as a screw hole. The screw can be sunk in this way in the end bracket.

Preferably, a screw head of the screw may extend in a cone shape to the screw shaft. In particular, the shape of the screw head can be adapted to the cone-shaped receptacle of the end holder. The screw head can rest in this way flat against the end bracket.

Generally, with a screw at the top of the screw head, a cross or longitudinal slot or internal polygon, e.g. Hexagon socket or square socket to be provided. Alternatively or additionally, the screw head may also have an outer polygon, e.g. External hexagon or square.

In particular, the sideline of the cone of the screw head closes with the top of the Screw head an angle between 40 ° and 50 °, preferably of 45 °, a. The screw can therefore be designed as a 90 ° angle screw.

In particular, the underside of the screw head can be designed such that the contact area with the end holder is kept low.

In coating processes, the screws are also partially sealed. These can thus grow on the Endhalterungen. A loosening of the screws turns out to be particularly difficult if there is a large contact area with the end bracket. In order to enable a better solubility of the screws, it is therefore advantageous if the screw head is as little as possible in contact with the end holder. Part of the sealing of the screws can be achieved, for example, in an acid bath. Then, since there is little contact with the end bracket, the bolt can be loosened and removed. Due to the low contact area thus the torque is affected when loosening the screw.

The holding device comprises a plurality of, in particular inventive supports, each having at least one support surface for a wafer, wherein the supports are releasably secured or attachable to the web.

There may be multiple supports, depending on the orientation of the holding device, side by side or one above the other. In particular, the bearing surfaces of the pads are oriented parallel to each other and / or to the end brackets.

Preferably, the distance between the pads is 5 mm to 9 mm, in particular 7 mm. Due to the parallel arrangement and the small distances between the supports a compact design is possible.

The bearing surfaces preferably extend at right angles to the web or to the webs.

Each edition can be attached to a bridge. Alternatively, a support can also be attached to a plurality of, in particular two, three or four, webs.

According to a further embodiment, the holding device is designed as a wafer boat. The wafer boat may in particular be oriented horizontally or vertically.

According to a further embodiment, the pads are suspended on the bridge, clamped, plugged, latched and / or screwed. The support can be easily releasably attached to the fixture. In particular, the assembly or disassembly of the support can be done without tools. A quick exchange is guaranteed.

According to a further embodiment, the web has recesses for the supports. The pads can be inserted in particular in the recesses and / or clamped therein.

According to a further embodiment, the web has securing receptacles for receiving securing lugs of the supports. In particular, the securing lug can be latched or pinned to the securing receptacle. As a result, unintentional release of the support can be prevented.

According to a further embodiment, the web comprises supports and counter-supports, wherein the supports, preferably the support surfaces, in each case between at least one support and at least one counter-support can be clamped. The support and the counter support are in particular offset from one another, i. not directly superimposed or juxtaposed.

According to a further embodiment, the support is associated with an upper side of the support, preferably the support surface, and the counter supports are associated with a lower side of the support, preferably the support surface. The support is in particular on the counter support, comparable with a rocker. The support forms an upper stop, so that the support can not tilt further. The support surface is therefore preferably in a horizontal holding device in a horizontal position.

In particular, the support is arranged closer to a fuse holder than the counter-support. The support and the counter support are thus offset from one another. Also, the counter-support can preferably be arranged closer to the fuse holder than the focus of the edition.

According to a further embodiment, at least two webs arranged parallel to one another and / or opposite one another are provided. The pads are attached to different webs. Each wafer is associated with at least two pads. For example, a wafer is held by two pads on two sides.

The pads can each be held on several, in particular two, webs. In this case, each edition can also have several, in particular two, securing devices, preferably securing lugs. Also, each bridge may include a fuse holder. So For example, a support, in particular on several webs, can be fastened detachably at the same time.

According to a further embodiment, the end mounts, the web and / or the pads are made of silicon or comprise silicon.

Silicon has several advantages. For example, silicon is relatively stable, so that a safe transport and maintenance are possible. Furthermore, silicon is heat resistant even at high temperatures. In addition, no impurities occur during processing, so that the holding device or the individual components must be replaced less often.

All aspects, embodiments and features of the invention described herein can be combined with each other, in particular also detached from the specific embodiment in the context of which they are mentioned. In particular, all subject matters of the dependent claims may be combined with each other and with each subject matter of the independent claims.

• 1 eine Perspektivansicht einer Ausführungsform einer erfindungsgemäßen Haltevorrichtung,
• 2 eine Detailansicht der Haltevorrichtung gemäß 1,
• 3 eine Detailansicht (Ausschnitt E der 2) der Haltevorrichtung gemäß 1,
• 4 eine Detailansicht (Ausschnitt F der 2) der Haltevorrichtung gemäß 1, und
• 5 eine Schnittansicht eines Ausschnitts der Haltevorrichtung gemäß 1.

The invention will now be described by way of example with reference to the drawings. Show it:

• 1 a perspective view of an embodiment of a holding device according to the invention,
• 2 a detailed view of the holding device according to 1 .
• 3 a detailed view (detail E of 2 ) of the holding device according to 1 .
• 4 a detailed view (detail F of 2 ) of the holding device according to 1 , and
• 5 a sectional view of a section of the holding device according to 1 ,

First, it should be noted that the illustrated embodiments are merely exemplary in nature. In particular, the number of webs and pads may vary. Also, the shape of the Endhalterungen, webs and / or cushions can be configured differently. For example, only one securing nose can be provided.

If a figure contains a reference numeral which is not explained in the directly associated descriptive text, reference is made to the corresponding preceding or following statements in the description of the figures. Thus, the same reference numerals are used for the same or comparable components in the figures and these are not explained again.

1 shows a horizontal holding device for horizontally oriented, not shown, wafers. Such a holding device is also called a horizontal boat.

The holding device comprises two plate-shaped end holders 10 , Between the end mounts 10 webs extend 12 , Two bars each 12 are arranged parallel to each other on opposite sides.

At the jetties 12 are several editions 14 releasably secured. The terms 14 are sickle-shaped.

For each wafer is a pair of opposing pads 14 provided, ie each wafer is held on two sides. Each edition 14 is detachably attached to two webs 12.

The detachable attachment can be a support 14 be easily exchanged, for example when the pad 14 is damaged.

Also the bars 12 can in particular be releasably attached to the end mounts 10 be attached. To attach this can screws 16 which are used in screw holes 18 the end mounts 10 can be introduced.

2 shows a detail view of in 1 shown holding device. Each edition 14 is at two jetties 12 releasably secured.

The edition 14 includes a support surface 20 and two security devices 22 , The security devices 22 have safety noses 24 on, which is both in the plane of the bearing surface 20 as well as extend at right angles.

A detail view of the sections E and F are in the 3 and 4 shown. The jetty 12 has a recess 26 on, in which the edition 14 , in particular a in the plane of the support surface 20 extending portion of the securing device 22 , is plugged. The slot-shaped recess 26 is for example also in the sectional view in 5 to see.

The safety nose 24 engages in a fuse holder 28 of the footbridge 12 one. This will prevent the overlay 14 unintentionally triggers.

During assembly, the requirements 14 at the jetties 12 pinned. These are detachable at the webs 12 attached and can be easily replaced, for example, in case of a defect.

The service life of a wafer boat can be significantly increased, thereby saving costs.

LIST OF REFERENCE NUMBERS

10

end support

12

web

14

edition

16

screw

18

screw

20

bearing surface

22

safety device

24

securing lug

26

recess

28

securing mount

Claims (15)

A holder (14) for a holding device for holding a plurality of wafers, comprising a support surface (20) for a wafer and a securing device (22) for releasably securing to the holding device. Edition after Claim 1 , characterized in that the securing device (22) comprises a hooking, clamping, plugging, latching and / or screwing device. Edition after Claim 1 or 2 , characterized in that the securing device (22) has a securing nose (24), which in particular can be brought into engagement with a securing receptacle (28) of a web (12) of the holding device. Edition after Claim 3 , characterized in that the securing lug (24) extends in the plane of the support surface (20). Edition after Claim 3 or 4 , characterized in that the securing lug (24) extends from the plane of the support surface (20). Pad according to one of the preceding claims, characterized in that the bearing surface (20) is plate-shaped, in particular sickle-shaped or annular, is formed. Holding device for holding a plurality of wafers, comprising two end mounts (10), at least one between the Endhalterungen (10) extending web (12) and a plurality of supports (14), in particular according to one of the preceding claims, each having at least one support surface (20) for a wafer, wherein the supports (14) are detachably fastened or attachable to the web (12). Holding device after Claim 7 , characterized in that the holding device is designed as a wafer boat. Holding device after Claim 7 or 8th , characterized in that the supports (14) on the web (12) can be suspended, clamped, plugged, latched and / or screwed. Holding device according to one of Claims 7 to 9 , characterized in that the web (12) has recesses (26) for the supports (14). Holding device according to one of Claims 7 to 10 , characterized in that the web (12) has securing receptacles (28) for receiving securing lugs (24) of the supports (14). Holding device according to one of Claims 7 to 11 , characterized in that the web (12) comprises supports and counter supports, wherein the supports (14), preferably the bearing surfaces (20), in each case between at least one support and at least one counter-support can be clamped. Holding device after Claim 12 , characterized in that the support of an upper side of the support (14), preferably the support surface (20), and the counter support of a bottom of the support (14), preferably the support surface (20) is assigned, in particular wherein the support closer to a Fuse holder (28) is arranged as the counter-support. Holding device according to one of Claims 7 to 13 , characterized in that at least two parallel and / or oppositely arranged webs (12) are provided, each wafer at least two pads (14) are associated, and wherein the supports (14) are attached to different webs (12). Holding device according to one of Claims 7 to 14 , characterized in that the end holders (10), the web (12) and / or the supports (14) consist of silicon or comprise silicon.

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