JPH01734A - Wafer transport jig - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention involves carrying a boat carrying semiconductor wafers into a high-temperature furnace tube, heat-treating the wafers, and carrying out the boat carrying the wafers after the heat treatment. Regarding the jig for
The present invention relates to a wafer transport jig suitable for heat treatment on a wafer boat in which a large number of large disk-shaped silicon wafers are arranged in parallel.

[Prior Art] Conventionally, in the heat treatment of semiconductor wafers, a large number of disc-shaped wafers are spaced side by side on a boat, the boat is carried into a heat treatment furnace tube using a transport jig, the wafers are heat treated, and then the wafers are heat-treated. This is done by inserting the jig into the furnace tube again, lifting the boat, and carrying it out. Such an operation is performed using a wafer boat transfer device, and in particular by horizontal movement and slight vertical movement of a gripping member attached to the device. The wafer transport jig is attached to the above-mentioned gripping member at the end of the tubular part, and the wafer separation boat is placed on the horizontal notch holding part on the other end side for transport operation.

As can be understood from this heat treatment operation, the wafer boat transfer jig attached to such a transfer device has a wafer boat holding portion formed with a notch on one side of a straight cylindrical quartz glass tube. Since it is inserted into a high-temperature furnace tube, it is required to have a high degree of heat resistance that is completely stable even at that high temperature. Therefore, as the material for such a jig, quartz glass, silicon carbide, or the like, which has excellent heat resistance and is as pure as possible, is used.

However, with the mass production of semiconductor chips and the demand for high yields, the diameter of the disk-shaped wafers to be heat-treated has increased, and the number of wafers to be heat-treated has also increased, resulting in larger and heavier wafer loading boats. Due to the significant increase in the number of wafers, the wafer boat transport jig used in the heat treatment apparatus has also become considerably larger.

Therefore, in particular, the notch base of the boat holding part (the starting part of the arcuate notch on the center side of the glass tube) on which the wafer boat of the heavy jig is placed is susceptible to damage due to the large bending moment acting there. In this technical field, the solution to this problem has been an important issue because the inconvenience of bending or bending is unavoidable.

[Problems to be Solved by the Invention] Accordingly, an object of the present invention is to provide a practically excellent wafer loading boat transport jig in which the bending strength of the notch base is improved.

[Means for Solving the Problems] As a result of repeated prototyping studies of a wafer boat transport jig that achieves the above object, the inventors have developed a jig that is easy to manufacture and is practically desirable.

That is, the present invention provides a wafer transport jig that meets the requirements set forth in the claims, and in particular, the notch starting part and its vicinity at the center of the quartz glass tube are made thicker than other parts. It has a technical feature in that it is formed and reinforced.

Therefore, the reinforcement of the notch starting part (base) of the quartz glass tube jig of the present invention is such that the notch base has sufficient strength for loading and unloading the wafer loading boat, as described above. Therefore, it is important to form the notch over a sufficient area to prevent damage or deflection of the notch base due to bending moment due to the load of the wafer boat.

The quartz glass jigs currently in use, for example, have an outer diameter of 100 to 120 mm and a length of approximately 2100 to 2500 m.
It is a large type in which a wafer boat mounting part is formed by cutting out about 800 to 900 mm from one end of a cylindrical quartz glass tube with a wall thickness of about 4.5 to 5 mm, and its weight is, for example, 2 kg. Therefore, considering the operability, it is preferable to reduce the weight by reducing the degree of reinforcement as much as possible, and to make it as small as possible to achieve the desired effect. good.

In addition, in the above-mentioned jig, a large force is applied to the end of the cylindrical part that is attached to the jig gripping member of the wafer transfer device, so the gripping part should be made thick to strengthen it. is extremely preferred.

Such a jig of the present invention, for example, linearly integrates a thin-walled tube of a predetermined length also made of quartz glass at both ends or one end of a thick-walled tube of a predetermined length made of quartz glass. Welded to create a single quartz glass tube with partially different thicknesses,
It can be easily manufactured by cutting out a predetermined portion thereof. Similarly, an integrated quartz glass tube with thick walls at both ends was made, one end of which was cut out, and a thin quartz glass plate with an arcuate cross section was pre-fabricated.
It is possible to weld to the edge of the notch, or it is also possible to create the above-mentioned integral quartz glass tube with partially different thicknesses by padding or the like.

[Example] Next, the jig of the present invention will be explained in more detail with reference to the accompanying drawings.

FIG. 1 is a perspective view showing an example of the wafer boat transfer jig of the present invention in use, and FIG. 2 is an axial cross-sectional view of the jig.

In the figure, the jig 1 starts cutting in an arc shape at a part near the center of the quartz glass cylinder, for example, about 1/3 from one end (notch start part) 2, and continues into the notch. A wafer boat holding portion 3 is formed by a notch parallel to the axis. Therefore, a thick layer 4 that is thicker than other parts is formed near the arc-shaped notch starting part 2, and the thick layer 4 is thicker than the other parts. In comparison, the reinforcement is, for example, about 3 times as thick, but for practical purposes, it is usually selected from a range of about 1.8 to 3.5 times. Further, as shown in the figure, the thick layer forming region is formed over a long range on the notch side and a short range on the cylindrical side. For example, the forming range from the notch starting part 2 to the notch side is as follows. Practically, it is preferable that the length of the notch is approximately 25 to 30% of the length of the notch in the axial direction, and that the range of formation on the cylindrical side is approximately 7 to 13% of the length of the notch. However, these ranges can be changed as appropriate in relation to the degree of reinforcement thickening and other conditions. This type of reinforcement effectively prevents breakage and deflection, especially near the notch, allowing a heavy wafer loading boat to be stably loaded, and to hold it stably and safely. A jig capable of carrying out the conveyance is provided.

Further, the end of the non-notched cylindrical portion of the jig is formed into a thick-walled tube 5 over a length that allows the portion gripped by the moving operation member of the wafer transfer device to be sufficiently reinforced.

The cylindrical reinforced end 5 of the jig 1 is firmly attached to the moving operation member 7 of the wafer transfer device 6, as shown in FIG. The boat 9 is loaded onto the boat 9, moved straight in the axial direction, inserted through the heat treatment furnace loading port 10, and then slowly lowered into the furnace and pulled out, leaving the boat 9 behind. Furthermore, after the wafer heat treatment, the wafer boat is carried out of the furnace by a completely reverse operation.

Example 1 The jig used had an outer diameter of 100 mm and a length of about 2510 mm.
Approximately 800 mm is cut out from one end of a cylindrical quartz glass tube with a wall thickness of approximately 4.5 mm to form the wafer boat mounting section, and the vicinity of the notch starting base on the center side of the jig is The notch side is approximately 223 mm thick, and the cylindrical side is approximately 55 mm thick, with a uniform thickness of approximately 12 mm.
It is formed over a length of mm.

Using the jig of the present invention, a wafer boat weighing about 4 kg was repeatedly carried into and out of a furnace at a temperature of about 1150° C. in order to heat-treat the boat.

On the other hand, a similar wafer boat heat treatment operation was performed using a jig of the same size and shape that was not thickened.

The average lifespan of the jig of the present invention was perfectly safe even after 56 uses, whereas the conventional one failed after only 32 uses.

Example 2 Using the same jig of the present invention as described above, in order to heat treat a wafer boat on which wafers having an outer diameter of 5" were mounted, the number of wafers was carried into and taken out of a furnace tube with an inner diameter of 173 mm. I changed it and repeated it.

The jig of the present invention was capable of loading and unloading an average of 250 wafers, whereas the conventional jig would bend or break after an average of 160 wafers, making loading and unloading difficult. .

[Effects of the invention] According to the reinforced wafer transport jig of the present invention, there is virtually no damage or deflection caused by the wafer boat, and it has excellent durability and has high practical value as a transport device for large wafer heat treatment. has.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of the jig of the present invention in use, and FIG. 2 is a sectional view of the jig. Reference numeral 21 in the figure: jig 6: wafer transport device 2: notch start portion 7: moving operation member 3: wafer holding portion 8: wafer 4: thick layer 9: boat Patent applicant Shin-Etsu Quartz Co., Ltd.

Claims (1)

[Claims] 1. In a wafer boat heat treatment transfer jig in which one end of a cylindrical quartz glass tube is notched in the axial direction to form a wafer boat holding section, a cross section of the center side of the tube is provided. A wafer transfer jig comprising a starting part of an arc-shaped notch and a thickness in the vicinity thereof that is thicker than other parts over an area sufficient to stably hold a wafer loading boat. 2. The wafer transfer jig according to claim 1, wherein the end of the uncut cylindrical portion is formed thick.