JP2002305231A - Longitudinal batch processor, mobile machine and conveying method for wafer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology required for increasing the number of wafers which can be stored in a device, by further reducing a distance between wafers for remarkably reducing costs. SOLUTION: When carrying a wafer out of a cassette and into the cassette by a robot arm 102, the position relation of the wafer and a wafer remained in the cassette is made into state like a figure 1 (c), at all times. In such a position relation, since the distance between wafers 101 and 103 does not become shorter than an inter-wafer distance (d) (figure 1 (e)), there is a margin in a conveyer and the inter-wafer distance (d) can be reduced further. When carrying a wafer out of the cassette and into the cassette, the position relation between the wafer and a wafer remained in the cassette is made into state like a figure 1 (d). Thus, since the interval between wafers becomes shorter than the inter- wafer distance (d), there is no margin in the conveyer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for transporting a large-area substrate, an apparatus for storing and processing a large-area substrate by transport, and a method for transporting a large-area substrate. The apparatus corresponds to a transfer machine, a vertical batch processing apparatus, or the like.
The vertical batch processing apparatus includes a vertical heat treatment apparatus.

[0002]

2. Description of the Related Art Generally, a heat treatment step is indispensable in a semiconductor device manufacturing process. The heat treatment step includes a thermal oxidation step of the semiconductor film, a crystallization step of the semiconductor film, and a hydrogenation step. A vertical batch processing apparatus is often used in this heat treatment step. A vertical batch processing apparatus used in a manufacturing process of a semiconductor device performs processing in a state where a plurality of substrates on which a semiconductor film is formed are arranged in a vertical direction, and thus is called by such a name. The vertical direction does not need to exactly match the direction of gravity. Some have been devised that are apparently slanted from the vertical. The plurality of substrates are adjacent to each other at a certain interval, and this interval is usually designed in the same manner between any two substrates. In this case, the perpendiculars of the substrates coincide with the vertical direction, and when a plurality of substrates are viewed from above the substrates, all the substrates appear to overlap. Although there is a similar apparatus called a horizontal batch processing apparatus, this apparatus performs processing by arranging a plurality of substrates in a horizontal direction. In this case, the perpendicular of the substrate coincides with the horizontal direction. A vertical batch processing apparatus is preferably used in a semiconductor device manufacturing process because the size of a footprint is suppressed as compared with a horizontal type batch processing apparatus. In general, the price per unit area of a clean room is very high, so that a device with a small footprint is required for cost reduction. Also, the vertical type has a feature that impurities are less likely to be mixed into the heat treatment chamber. An overview of the vertical heat treatment apparatus will be described with reference to FIG. In order to prevent impurities from entering, the room where the substrate is heat-treated
1 around the heater unit 2
02 is arranged. The heater unit can raise the temperature of the substrate to a desired temperature. Below the quartz tube 201 is a quartz boat 203 for storing substrates,
Below that, a quartz table 204 is arranged. A plurality of protrusions for supporting the substrate are formed on the quartz boat 203, and by holding the substrate on these protrusions,
A plurality of substrates can be stored in a quartz boat. A quartz table 204 is provided below the quartz boat 203, and is usually arranged in a quartz tube at a portion where the temperature is not uniform. After the substrates are stored in the quartz boat 203, the boat
3 is moved upward and stored in a quartz tube. When the quartz boat moves to the top, the inside of the quartz tube is sealed. Thereby, the atmosphere in the heating area can be controlled. In addition, by covering the quartz tube with the high-pressure container 206, it is possible to control the pressure in the quartz tube. In order to take the substrate in and out of the quartz boat, a transfer method using a robot is generally employed. That is, a method is generally adopted in which a substrate is placed on a robot arm and carried into and out of a quartz boat one by one. In addition, what accommodates the substrate as represented by the quartz boat is referred to as a cassette in this specification. Examples of apparatuses using a cassette include a transfer machine, a vertical batch processing apparatus, a vertical heat treatment apparatus, and a substrate cleaning apparatus.

[0003]

The size of a glass substrate used in a mass production factory for semiconductor devices formed on the glass substrate is, for example, each side having a length of 300 × 400 mm or 600 × 720 mm. , The thickness is 0.3 ~
It is about 1.1 mm. The thickness of the glass substrate tends to be reduced due to demands for weight reduction and cost reduction of the substrate, and the standard thickness in the future is considered to be about 0.4 to 0.8 mm. Therefore, in order to transfer such an extremely thin large-area substrate on the robot arm, it is necessary to design an apparatus in consideration of the warpage of the substrate. In fact, when a large-area substrate is transported using a robot arm, it can be seen that the substrate is greatly bent. Therefore, when storing the substrates in the quartz boat, adjacent substrates will come into contact with each other unless the distance between the substrates is made large to some extent. However, if the distance between the substrates is too large, either the height of the ceiling of the clean room becomes too high, or the number of substrates that can be processed at one time in the vertical batch processing apparatus becomes too small. In any case, these problems lead to high costs. In particular, in the case of a vertical heat treatment apparatus, since the cost of one process is very high, an improvement in the processing capacity leads to a large cost reduction.
The present invention provides a technique necessary for increasing the number of substrates that can be accommodated in an apparatus by further reducing the distance between the substrates.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems by improving the procedure for transferring a substrate. Or,
The above problem is solved by devising the shape of the robot arm and the shape of the cassette in which the substrates are stored. The present invention will be described with reference to FIG. Generally, when the substrate 101 is held by the robot arm 102, warpage occurs due to the weight of the substrate. The amount of this warpage is defined as t1. (FIG. 1A) A substrate 103 similar to the substrate 101 is placed on a quartz boat 10.
When the substrate is accommodated in the substrate, the substrate is warped due to its own weight. The amount of this warpage is defined as t2. (Fig. 1 (b))
The substrate 103 is held by the protrusion 105. The thickness of the robot arm is set to t3. Here, a case where the substrates are stored in a quartz boat in order from the top is considered. In this case, this corresponds to FIG. 1 (d), and the center between the substrate stored immediately before and the substrate to be stored next comes very close due to the warpage of the substrate. It is necessary to increase the width more than when there is no warpage. Quartz boat 10
Assuming that the distance between adjacent substrates when the maximum number of substrates is put in 4 is d, when the substrates are stored in order from above, the distance between the substrates is d− (t1 + t2). FIG. 1E shows the distance d between the substrates. Here, the inter-substrate distance d is usually a constant value, but if there is a different inter-substrate distance, it is defined by their minimum value. Therefore, d> t1 + t2 (1) must be satisfied. In general, as the substrate becomes larger and the substrate becomes thinner, t1 + t2
Is larger, so that conditional expression (1) is more restrictive. Currently, the size of a glass substrate used in a mass production site is about 600 × 720 mm on each side, and the thickness is about 0.4 to 0.8 mm. When a thickness of 0.7 mm is used, t1 = 5 mm and t2 = 10 mm. These values are
Although it largely depends on the width of the robot arm and the length of the projection 105 of the quartz boat, the width of the robot arm is 100
mm and the length of the projection 105 of the quartz boat was set to several mm to about several tens mm. At this time, conditional expression (1) is d
> 15 mm. Due to the operation of the machine, there must be enough room above and below the robot arm when loading and unloading substrates.
When the substrates are loaded sequentially from above the quartz boat, the necessary margin above the substrate on the robot arm is D1, and the margin below the substrate on the robot arm is D.
Let 2. (FIG. 7 (a)) Since it is better that both D1 and D2 are at least about 5 mm, the distance d between the substrates is 15 + 5 +
5 = 25 mm or more is better. Since D1 and D2 greatly depend on the operation accuracy of the robot, the higher the accuracy, the smaller the value can be. From the gist of the present invention, D
Needless to say, it is preferable that D1 and D2 be as small as possible. That is, conditional expression (1) is further restricted, and d> t1 + t2 + D1 + D2 (2). On the other hand, when the substrates are stored in order from below the quartz boat, this corresponds to FIG. 1C, and d is limited by the following equation. That is, d> t3 (3). Since t3 is generally about 5 to 10 mm,
Conditional expression (3) is less restrictive than conditional expression (1). In addition, since the value of t3 becomes smaller as the strength of the arm increases, the limit of the conditional expression is further reduced. Therefore, if the substrates are stored in order from the bottom of the quartz boat, and if the distance between the substrates satisfies conditional expression (3), the distance d between the substrates can be reduced, the number of substrates that can be stored in the quartz boat increases. And the processing efficiency is improved. In order to have a margin above and below the substrate as considered in the conditional expression (1), the expression (3) is restricted, and d> t3 + d1 + d2 (4). Here, when the substrates are unloaded in order from above the quartz boat, a necessary margin above the robot arm is d1, and a necessary margin below the robot arm is d.
Let 2. (FIG. 7B) Both d1 and d2 should be at least about 5 mm. Since d1 and d2 greatly depend on the operation accuracy of the robot, the higher the accuracy, the more
Its value can be reduced. From the gist of the present invention, d1, d2
It is needless to say that it is preferable that is as small as possible. Here, due to the structure of the transport device, d1 + d2 is D1 + D2.
It can be considered almost the same as From the above considerations, the present invention is characterized in that the substrates are sequentially carried out from above the cassette and that the substrates are carried in from below the cassette. Therefore,
From the expressions (2) and (4), the distance d between the substrates that can be set only by the present invention is t1 + t2 + D1 + D2 = t1 + t2 + d1 + d2>d> t3 + d1 + d2 (5) Becomes To make d2 as small as possible, it is advisable to devise the shape of the robot arm. This will be described with reference to FIG. In order to make d2 smaller, the lower surface of the robot arm 218 may have a curvature 1 convex outward. That is, in this case, the robot arm 21
8, when the substrate is carried in and out, the robot arm 218
Since the probability of contact between the substrate 103 located below and the robot arm 218 is reduced, d2 can be designed to be smaller. The curvature 1 may be equal to the curvature of the substrate held by the protrusion 105. In addition, in order to reduce the probability of a substrate transfer error, the curvature of the warp of the substrate held by the robot arm and the curvature protruding outward on the upper surface of the robot arm are matched with each other, so that the When the contact area with the arm is increased, the frictional force is dispersed in the substrate, and the substrate is hardly damaged, which is preferable. In addition, when the contact area is large, the transfer of the substrate takes a stable period, so that the transfer can be performed with higher accuracy. Therefore,
d1 and d2 can be designed to be small. Details are described in Example 3. To make d1 and d2 smaller, for example,
As in the projection 216 shown in FIG. 10D, the surface holding the substrate and the surface located below the surface are inclined with respect to the horizontal plane, and the inclination is in the direction in which the volume of the space in the cassette increases. It is good to attach to. As a result, the volume of the space in the cassette increases, and the probability of contact between the substrate and the cassette further decreases. When a vertical heat treatment apparatus is used in a vertical batch processing apparatus, the object to be processed may react with the atmosphere and deteriorate due to the heat treatment. Therefore, the heat treatment is preferably performed under reduced pressure. The pressure reduction condition is suitably in the range of 10 to 10000 Pa in consideration of the heating efficiency and the effect of preventing deterioration. In addition, the present invention can be applied to a plasma processing apparatus and the like. However, the plasma processing apparatus has a decompression unit, and the present invention can be applied to a vertical batch processing apparatus having a decompression unit. The shape of the robot arm may be a fork-shaped robot arm 1100 as shown in FIG. Also, other shapes may be used. The present invention will be listed below. The present invention is directed to a vertical batch processing apparatus having a cassette in which a plurality of substrates are stored in a vertical direction and a robot arm for transporting the substrates, wherein, among the plurality of substrates stored in the cassettes, The relationship between the distance d, the thickness t3 of the robot arm, the warp t1 of the substrate generated when the substrate is held by the robot arm, and the warp t2 generated on the substrate stored in the cassette Is the conditional expression t1 + t2 + d1 + d2>d> t3 +
d1 + d2, where d1 is the distance between the robot arm and the substrate located above the robot arm when the substrate is carried in and out of the cassette, and d2 is the cassette of the substrate. A vertical batch processing apparatus, which is a distance between the robot arm and the substrate positioned below the robot arm when the substrate is carried in and out of the robot arm. According to another configuration of the present invention, in a transfer machine including a cassette in which a plurality of substrates are stored in a vertical direction and a robot arm that transports the substrates, the transfer device includes an adjacent one of the plurality of substrates stored in the cassette. A distance d between the substrates,
The thickness t3 of the robot arm, and the warp t1 of the substrate caused when the substrate is held by the robot arm
And the warpage t2 generated in the substrate stored in the cassette
Is the relational expression t1 + t2 + d1 + d2>d> t3 + d1 + d
2, d1 is the distance between the robot arm and the substrate located above the robot arm when the substrate is carried in and out of the cassette, and d2 is the distance of the substrate from the cassette to the cassette. In a transfer machine, the distance is a distance between the robot arm and the substrate located below the robot arm when the robot arm is carried in and out. Another configuration of the present invention is a method for transferring a substrate via a robot arm from a cassette 1 storing a plurality of substrates in a vertical direction to a cassette 2 storing a plurality of substrates in a vertical direction. A distance d3 between adjacent substrates among a plurality of substrates stored in the cassette 1 and a distance d between smaller substrates among distances d4 between adjacent substrates among the plurality of substrates stored in the cassette 1; A larger one of a thickness t3 of the robot arm, a warp t1 of the substrate generated when the substrate is held by the robot arm, and a warp generated in the substrate stored in the cassette 1 or the cassette 2. Is related to the warpage t2 of the conditional expression t1 + t2 + d1 + d
2>d> t3 + d1 + d2, where d1 is a distance between the robot arm and the substrate located above the robot arm in the cassette 1 or the cassette 2 when the substrate is loaded or unloaded. D2 is a distance between the robot arm and the substrate located below the robot arm when the substrate is carried in and out of the cassette 1 or the cassette 2; A substrate transfer method is characterized in that substrates carried out by the robot arm are carried out in order from the top, and substrates carried in the cassette 2 by the robot arm are carried in in order from the bottom. Another configuration of the present invention is a method for transferring a substrate via a robot arm from a cassette 1 storing a plurality of substrates in a vertical direction to a cassette 2 storing a plurality of substrates in a vertical direction. Distance d between adjacent substrates among a plurality of substrates stored in
3, the distance d between the larger one of the distances d4 between the adjacent substrates among the plurality of substrates stored in the cassette 1, the thickness t3 of the robot arm, and the substrate The relationship between the warp t1 of the substrate generated in the state held in the above and the larger warp t2 of the warp generated in the substrate stored in the cassette 1 or the cassette 2 is represented by a conditional expression t1 + t2 + d1 +. d2>d> t3 + d1 + d2
Where d1 is the distance between the robot arm and the substrate located above the robot arm when loading and unloading substrates in the cassette 1 or the cassette 2, and d2 is the cassette A distance between the robot arm and the substrate positioned below the robot arm when the substrate is loaded or unloaded in the cassette 1 or the substrate 2; Are carried out in order from the top, and the substrates carried into the cassette 2 by the robot arm are carried in in order from the bottom. Another configuration of the present invention is a method of transporting a substrate using a unit having a cassette in which a plurality of substrates are stored in a vertical direction and a robot arm that transports the substrate, wherein the plurality of substrates are stored in the cassette. Among the substrates, the distance d between adjacent substrates, the thickness t3 of the robot arm, the substrate warpage t1 generated when the substrate was held by the robot arm, and the substrate stored in the cassette The relationship with the warpage t2 generated in the substrate is represented by the conditional expression t1 + t2 + d1 + d2> d.
> T3 + d1 + d2, where d1 is the distance between the robot arm and the substrate located above the robot arm when the substrate is carried in and out of the cassette;
d2 is a distance between the robot arm and the substrate positioned below the robot arm when the substrate is carried in and out of the cassette, and the robot arm moves the plurality of substrates under the cassette. A method of transporting a substrate, comprising a step of sequentially loading the substrate from a side.
Another configuration of the present invention is a method of transporting a substrate using a unit having a cassette in which a plurality of substrates are stored in a vertical direction and a robot arm that transports the substrate, wherein the plurality of substrates stored in the cassette are provided. Of the substrates, the distance d between adjacent substrates, the thickness t3 of the robot arm, the substrate warpage t1 generated when the substrate was held by the robot arm, and the substrate contained in the cassette The relationship with the warpage t2 generated in the substrate is represented by the conditional expression t1 + t2 + d1 + d2>d> t3
+ d1 + d2, where d1 is the distance between the robot arm and the substrate located above the robot arm when the substrate is carried in and out of the cassette, d2
Is the distance between the robot arm and the substrate located below the robot arm when the substrate is carried in and out of the cassette, and the robot arm moves the plurality of substrates from above the cassette. A method of transporting a substrate, comprising a step of sequentially carrying out the substrate. In the above invention, it is preferable that the vertical batch processing apparatus be a vertical heat treatment apparatus because running costs can be further reduced. In addition, it is preferable that the vertical heat treatment apparatus include a decompression unit because a reaction between the atmosphere and the object to be processed is suppressed and the quality of the object to be processed due to the heat treatment is suppressed. An appropriate pressure range during the heat treatment is 10 to 10000 Pa. The above ranges were determined for the purpose of heating efficiency and suppressing the reaction. In the above invention, the size of each side of the substrate is 300 × 400 mm or more, and the thickness of the substrate is 0.3
It is suitable to apply the present invention if it is 1.11.1 mm. The thickness of the substrate is preferably 0.4 to 0.8 mm for applying the present invention. In the above invention, it is preferable that the upper surface of the robot arm has a curvature that is convex toward the outside of the robot arm, because the transfer accuracy is further improved. It is preferable that the lower surface of the robot arm has a convex curvature toward the outside of the robot arm, because the distance between the substrates stored in the cassette can be reduced. In the above invention, the protrusion holding the substrate of the cassette holds the substrate on a surface inclined from a horizontal plane, and the inclined surface is a surface whose height decreases toward the center of the substrate, This is preferable because the distance between the substrates stored in the cassette can be further reduced. In the above invention, when the surface of the protrusion that holds the substrate of the cassette that is located below the surface that holds the substrate is a surface whose height increases toward the center of the substrate, the protrusion is stored in the cassette. This is preferable because the distance between the substrates can be reduced.

[0005]

(Embodiment 1) In this embodiment,
A case where the vertical batch processing apparatus of the present invention is used for crystallization of a semiconductor film to be a semiconductor layer (active layer) of a TFT will be described with reference to FIG.

First, a base film 11 made of a 200-nm-thick silicon oxynitride film and a 55-nm-thick amorphous semiconductor film (in this embodiment, an amorphous silicon A film 12 is formed. In this step, the base film and the amorphous silicon film may be formed continuously without being exposed to the atmosphere.

Next, an aqueous solution (nickel acetate aqueous solution) containing 10 ppm by weight of a metal element (nickel in the present embodiment) is applied by spin coating to form a metal element-containing layer 13.
Is formed on the amorphous silicon film 12. Metal elements usable here include palladium (Pd), tin (Sn), lead (Pb), cobalt (C
o), platinum (Pt), copper (Cu), and gold (Au).

In this embodiment, the method of adding nickel by the spin coating method has been described, but the metal element may be added by a method such as an evaporation method or a sputtering method. (FIG. 3
(A)) Next, the substrate on which the semiconductor film to which the metal element is added is formed is carried into a quartz boat by a transfer robot and stored therein. The transfer robot has a robot arm made of ceramic and having a thickness of 10 mm, and the distance d between the substrates is set to 20 mm according to the conditional expression (4). At this time, d1 = d2 = 5
mm. The substrates are stored in a quartz boat capable of storing 60 substrates. When the substrates are sequentially loaded from below the quartz boat, since t3 = 10 mm and d = 20 mm at this time, there is a margin of 10 mm and the loading is relatively easy. When loading the board,
If the method of packing the substrates in order from the top is adopted, the conditional expression of the distance d between the substrates is expressed by the formula (2). Since t1 + t2 is about 15 mm, if d = 20 mm, the formula (2) must not be satisfied. Becomes difficult to carry.

After storing the substrates in the quartz boat 203, the quartz boat 203 is moved upward by the boat elevator unit 205, and the substrates are stored in the quartz tube 201. In order to prevent oxidation of the semiconductor film due to heat treatment, the inside of the quartz tube 201 is set to a nitrogen atmosphere, and heating is started. For example,
First, a heat treatment is performed at 400 to 500 ° C. for about 1 hour to desorb hydrogen contained in the film.
The amorphous silicon is crystallized by performing heat treatment at 650 ° C. for 4 to 12 hours to obtain the crystalline silicon film 14. ((B) of FIG. 3) (Embodiment 2) In Embodiment 2, a method for removing a metal element from the crystalline silicon film manufactured in Embodiment 1 will be described. This method is generally called a gettering step.
An insulating film 16 having a thickness of 200 nm is formed on the crystalline silicon film 14 as a mask made of a silicon oxide film.
5 is formed. A step of adding an element belonging to Group 15 of the periodic table (phosphorus in this embodiment) to the crystalline silicon film 14 exposed from the opening 15 is performed. By this step, a gettering region 17 containing phosphorus at a concentration of 1 × 10 ¹⁹ to 1 × 10 ²⁰ atoms / cm ³ is formed. The method of adding phosphorus may be, for example, a doping method.

A crystalline silicon film to which phosphorus has been added is carried into a vertical batch processing apparatus capable of heat treatment, and stored in a quartz tube. The loading method may be the method described in the first embodiment. Then, a rotary pump inside the quartz tube,
Vacuum is drawn by a mechanical booster pump, and nitrogen of high purity (concentration of CH ₄ , CO, CO ₂ , H ₂ , H ₂ O and O ₂ contained in nitrogen is 1 ppb or less) is flowed at 5 l / min. The pressure inside the quartz tube is maintained at 13.3 to 26.7 Pa, and a nitrogen atmosphere having an oxygen concentration of 5 ppm or less (2 ppm or less in this embodiment) is created. 450 ° C in this nitrogen atmosphere
A heat treatment process is performed at ６650 ° C. for 4 to 24 hours. In this embodiment, the atmosphere is a nitrogen atmosphere. However, if the oxygen concentration can be reduced to 5 ppm or less, the atmosphere may be a gas containing no oxygen, for example, an inert gas such as helium (He), neon (Ne), or argon (Ar). Good. Further, a gas that does not deposit by thermal decomposition or reacts with the semiconductor film, for example, hydrogen (H ₂ ) may be used.

By this heat treatment step, nickel in the crystalline silicon film 14 moves in the direction of the arrow, and is captured in the gettering region 17 by the gettering action of phosphorus. That is, nickel is removed from the crystalline silicon film 14, and the concentration of nickel contained in the crystalline silicon film 14 is 1 × 10 ¹⁷ atoms / cm ³ or less, preferably 1 × 10 ¹⁶ at.
oms / cm ³ or less.

The crystalline silicon film 14 formed as described above uses a metal element that promotes crystallization, and after the crystallization, the metal element is removed by the gettering action of phosphorus. Since the concentration of the metal element remaining in the crystalline silicon film 14 is reduced, a good crystalline silicon film can be obtained.

[0013]

(Embodiment 1) In this embodiment, an example of a transfer machine using the substrate transfer method of the present invention will be described. An embodiment will be described with reference to FIG. In FIG. 4, what is located in the center is
A robot arm 207 for transferring a substrate. The direction of rotation can be changed by the rotation means, and expansion and contraction are also possible. First, the robot arm 207 carries the substrate 1 from the uppermost substrate 1 of the cassette 208 in which the substrates are stored to the lowermost position 10 of the cassette 209 in which the substrates are not stored. Next, the cassette 208 in which the substrates are stored
Is moved to the position 11 of the cassette 209 where the substrates are not stored. By repeating these series of operations, all the substrates stored in the cassette 208 can be moved to the cassette 209. By following this rule, the positional relationship between the substrate and the robot arm when the substrate is carried in and out is the same as in FIG. 1C. Therefore, since the equation for limiting the distance between the substrates is (4), the condition for the distance d between the substrates is relaxed, and the distance between the substrates can be further reduced. (Embodiment 2) In this embodiment, an example in which a relatively narrow distance between substrates produces industrially good results will be described. Specifically, in the heat treatment process of the manufacturing process of the semiconductor device, the value of the contact resistance between the gate electrode and the wiring of the semiconductor device is
In the vertical batch processing apparatus for performing the heat treatment, the case where the distance between the substrates is small and the case where the distance between the substrates is large are different. In this example, the process of fabricating the TFT was omitted, and an example in which a stacked film of TaN and W was used as a gate electrode and the difference in contact chain resistance when Al-Nd was used for the gate wiring was experimentally examined. Show. First, TaN is deposited to a thickness of 30 nm on one side of a quartz substrate, and then W is continuously applied to a thickness of 370 nm.
A film was formed. Before film formation, the quartz substrate was sufficiently washed. Specifically, cleaning with pure water and cleaning with megasonic were performed.

After that, for the purpose of forming a contact chain, the laminated film of TaN and W was patterned and further subjected to thermal annealing. In the manufacturing process of the semiconductor device, the thermal annealing is performed, for example, in a process of activating a dopant doped in an active layer, a process of gettering impurities in a channel region of a TFT, and the like. Generally, a vertical batch processing apparatus is often used for such a thermal annealing step. The appropriate temperature for the thermal annealing in the activation step and the gettering step was about 450 to 600 degrees. FIG. 5 shows an overview of the vertical batch processing apparatus used in this experiment. The experimental substrate is housed in a quartz boat 211 surrounded by a quartz tube 210. In order to carry out experiments by changing the distance between adjacent substrates during the heat treatment, a cleaned quartz substrate is arranged at addresses 1 to 20, 23 to 60 in FIG. 5, and TaN is applied to addresses 21 and 22, 68 and 76. The substrate on which the laminated film of W was formed was arranged. Thus, address 2
The substrates arranged at 1 and 22 were used in experiments where the substrate spacing was small, and the substrates arranged at addresses 68 and 76 were used for experiments where the substrate spacing was wide. The distance between the substrates at addresses 21 and 22 was 5 mm, and the distance between the substrates at addresses 68 and 76 was 50 mm. In this embodiment, thermal annealing was performed for 4 hours under a nitrogen atmosphere at 600 degrees and atmospheric pressure. Nitrogen is supplied from the gas supply pipe 212 while the inside of the quartz tube is evacuated from the vacuum pump 220 through the valve 219 to make the quartz tube 210 have a nitrogen atmosphere. At this time, nitrogen was supplied from the gas supply pipe 503 at 5000 cm ³ per minute.
Shed. During the heat treatment, the oxygen concentration was about 15 ppm in the atmosphere inside the quartz tube. Thereafter, a film of Al-Nd was formed, and a contact chain was formed by patterning. The number of stages of the contact chain was 50. FIG. 6 shows the result of measuring the contact chain resistance. The contact chain resistance of the substrate arranged at the address 21 is very small and small in the vicinity of several tens Ω, whereas the contact chain resistance of the substrate arranged at the address 68 is several tens to 100 Ω. It varied greatly in the range up to near. From this result, it can be said that the shorter the distance between the substrates during the heat treatment, the more the variation in the contact resistance can be suppressed. That is, this experiment showed that shortening the distance between the substrates also leads to improvement in the characteristics of the semiconductor device. It is speculated that the cause of such a result may be the effect of oxidation of W. This phenomenon can be explained by considering that the reduction in the distance between the substrates made the efficiency of oxidation of W inferior and the deterioration of characteristics suppressed. As another method of suppressing the amount of oxygen, the inside of the quartz tube may be evacuated to maintain the pressure at 10 to 10,000 Pa. At this time, the atmosphere in the quartz tube is preferably nitrogen. (Embodiment 3) In this embodiment, an example is shown in which the distance between the substrates is further reduced by changing the shape of the robot arm and the shape of the protrusion 105 supporting the substrates described with reference to FIG. The robot arm shown in this embodiment has a margin for the transfer of the substrate, and does not easily damage the substrate. This embodiment will be described with reference to FIGS. FIG. 8A is a view similar to FIG. 7 except that the shape of the robot arm 213 is different. Robot arm 2
13 has a curvature at a portion in contact with the substrate,
The curvature approximately matches the curvature of the substrate formed when the substrate 103 is held by the robot arm 213. This significantly increases the area of the portion where the robot arm 213 and the substrate 103 are in contact with each other, so that the probability of damaging the substrate is significantly reduced. FIG. 8B is an example in which the shape of the projection 105 supporting the substrate is changed. The lower part of the protrusion 214 is a surface that is inclined with respect to the horizontal direction, and the shape of this surface approximately matches the warpage of the substrate at the end of the substrate 103 when the robot arm 213 holds the substrate 103. Thus, when the substrate 103 is stored in the quartz boat 104, the probability of contact between the substrate 103 and the protrusion 214 can be reduced. Therefore, the design allows more time,
The distance between the substrates can be further reduced. Fig. 8 (c)
Is an example in which the upper part of the projection is inclined with respect to the horizontal plane.
When the protrusion 215 holds the substrate 103, the contact area between the substrate 103 and the protrusion 215 is significantly increased, so that the substrate 103 is not easily damaged. FIG. 8D shows an example in which both the upper and lower portions of the projection are inclined with respect to the horizontal plane. Due to these inclinations, FIG.
The protrusion 214 shown in FIG. 8B and the protrusion 2 shown in FIG.
The protrusion 216 can have both of the 15 characteristics. FIG. 9A shows an example in which the lower portion of the robot arm 217 has a curvature. Thereby, the robot arm 217
Can further reduce the distance d2 between the substrate 103 and the robot arm 217 located below. Also,
FIGS. 9B to 9D are examples in which the shapes of the protrusions are modified similarly to FIGS. 8B to 8D. These effects are similar to those of FIG. FIG. 10A shows an example in which the upper and lower portions of the robot arm 218 have a curvature. This has an effect obtained by adding the effects of the robot arm 213 and the robot arm 217. FIGS. 10B to 10D are examples in which the shapes of the projections are modified similarly to FIGS. 8B to 8D. These effects are similar to those of FIG.

[0015]

By applying the present invention, the number of substrates that can be accommodated per unit volume increases, and the productivity increases.
The present invention is particularly effective when applied to a vertical batch processing apparatus, and contributes to a great cost reduction if the processing content is related to heat treatment. Further, when the present invention is applied to a manufacturing process of a semiconductor device, characteristics can be improved.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a side view showing a vertical batch processing apparatus.

FIG. 3 is a side view showing an embodiment of the present invention.

FIG. 4 is a side view showing an embodiment of the present invention.

FIG. 5 is a side view showing an embodiment of the present invention.

FIG. 6 is a graph showing the effect of the present invention.

FIG. 7 is a side view showing one embodiment of the present invention.

FIG. 8 is a side view showing an embodiment of the present invention.

FIG. 9 is a side view showing an embodiment of the present invention.

FIG. 10 is a side view showing an example of the embodiment of the present invention.

FIG. 11 is a diagram showing an example of an embodiment of the present invention.

[Explanation of symbols]

 101 Substrate 102 Robot arm 103 Substrate 104 Quartz boat 105 Projection 201 Quartz tube 202 Heater unit 203 Quartz boat 204 Quartz table 205 Boat elevator unit 206 High-pressure vessel 207 Robot arm 208 Cassette 209 Cassette 210 Quartz tube 211 Quartz boat 212 Gas supply pipe 213 Robot arm 214 Projection 215 Projection 216 Projection 217 Robot arm 218 Robot arm 219 Valve 220 Vacuum pump

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H01L 21/324 H01L 21/324 S // C23C 16/44 C23C 16/44 F F term (Reference) 3C007 AS01 DS01 ES17 ES17 EV04 EW00 NS12 4K030 CA06 CA12 DA09 GA02 GA12 JA03 KA04 LA15 5F031 CA05 DA01 EA06 FA02 FA07 FA11 GA05 GA32 GA47 GA48 GA49 HA65 MA28 MA30 NA04 PA13 PA18 PA30 5F052 AA13 AA17 CA10 DA02 EA15 EA16 FA06 JA01

Claims (34)

[Claims] In a vertical batch processing apparatus having a cassette in which a plurality of substrates are stored in a vertical direction and a robot arm for transporting the substrates, an adjacent substrate among the plurality of substrates stored in the cassette is provided. Of the robot arm, the thickness t3 of the robot arm, the warp t1 of the substrate generated when the substrate is held by the robot arm, and the warp t2 generated in the substrate stored in the cassette. The relationship satisfies the following conditional expression: t1 + t2 + d1 + d2>d> t3 + d1 + d2, and d1 is the robot arm and the robot arm located above the robot arm when the substrate is carried in and out of the cassette. A distance between the robot arm and the substrate located below the robot arm when the substrate is carried in and out of the cassette. Mold batch processing Equipment. 2. The substrate according to claim 1, wherein the area of the substrate is 1200.
And a 300 mm ² or more, vertical batch processing apparatus, wherein the thickness of the substrate is 0.3 to 1.1 mm. 3. The substrate according to claim 1, wherein each side of the substrate has a size of 300 × 400 mm or more, and the thickness of the substrate is 0.1 mm.
A vertical batch processing apparatus having a size of 3 to 1.1 mm. 4. The substrate according to claim 1, wherein the area of the substrate is 1200.
And a 300 mm ² or more, vertical batch processing apparatus, wherein the thickness of the substrate is 0.4 to 0.8 mm. 5. The substrate according to claim 1, wherein each side of the substrate has a size of 300 × 400 mm or more, and the thickness of the substrate is 0.1 mm.
A vertical batch processing device having a size of 4 to 0.8 mm. 6. The method according to claim 1, wherein
A vertical batch processing apparatus, wherein the upper surface of the robot arm has a curvature that is convex toward the outside of the robot arm. 7. The method according to claim 1, wherein
A vertical batch processing apparatus, wherein the lower surface of the robot arm has a curvature convex toward the outside of the robot arm. 8. The method according to claim 1, wherein
A vertical batch processing apparatus, wherein upper and lower surfaces of the robot arm have curvatures protruding outward from the robot arm. 9. The method according to claim 1, wherein
The projection holding the substrate of the cassette holds the substrate on a surface inclined from a horizontal plane, and the inclined surface is a surface whose height decreases toward the center of the substrate. Mold batch processing equipment. 10. The cassette according to claim 1, wherein the surface of the cassette, which holds the substrate holding the substrate, is located below the surface holding the substrate, and has a height toward the center of the substrate. A vertical batch processing apparatus characterized in that the number of surfaces increases. 11. The cassette according to claim 1, wherein the projection holding the substrate of the cassette holds the substrate on a surface 1 inclined from a horizontal plane, and the surface 1 is provided at the center of the substrate. Vertical batch processing characterized in that the height of the projections decreases below the surface 1 and the height of the protrusions 2 located below the surface 1 increases toward the center of the substrate. apparatus. 12. The vertical batch processing apparatus according to claim 1, wherein the vertical batch processing apparatus is a heat treatment apparatus. 13. A vertical batch processing apparatus having a cassette in which a plurality of substrates are stored in a vertical direction, a robot arm for transporting the substrates, and a decompression means, wherein a plurality of substrates stored in the cassette are adjacent to each other. Distance d between substrates
And the thickness t3 of the robot arm, and the warpage of the substrate caused when the substrate is held by the robot arm.
t1 and the warpage generated on the substrate stored in the cassette
The relationship with t2 is determined by the conditional expression t1 + t2 + d1 + d2>d> t3 + d1 +
d2 is satisfied, and d1 is the distance between the robot arm and the substrate located above the robot arm when the substrate is loaded / unloaded into / from the cassette, and d2 is the loading / unloading of the substrate into / from the cassette. A vertical batch processing apparatus, wherein a distance between the robot arm and the substrate located below the robot arm is set. 14. The substrate according to claim 13, wherein the area of the substrate is 12
0000 mm ² or more, the thickness of the substrate is 0.3 to 1.1 mm
A vertical batch processing apparatus, characterized in that: 15. A vertical batch processing apparatus according to claim 13, wherein each side of said substrate has a size of 300 × 400 mm or more, and said substrate has a thickness of 0.3 to 1.1 mm. 16. The substrate according to claim 13, wherein the area of said substrate is 12
0000 mm ² or more, and the thickness of the substrate is 0.4 to 0.8 mm
A vertical batch processing apparatus, characterized in that: 17. A vertical batch processing apparatus according to claim 13, wherein each side of said substrate has a size of 300 × 400 mm or more, and said substrate has a thickness of 0.4 to 0.8 mm. 18. The vertical batch processing apparatus according to claim 13, wherein said vertical batch processing apparatus is a heat treatment apparatus. 19. The vertical batch processing apparatus according to claim 13, wherein said pressure reducing means is controllable within a pressure range of 10 to 10000 Pa. 20. In a transfer machine having a cassette in which a plurality of substrates are stored in a vertical direction and a robot arm for transporting the substrates, between a plurality of substrates stored in the cassette, between adjacent substrates. The relationship between the distance d, the thickness t3 of the robot arm, the warp t1 of the substrate generated when the substrate is held by the robot arm, and the warp t2 generated in the substrate stored in the cassette is shown in FIG. , Conditional expression
t1 + t2 + d1 + d2>d> t3 + d1 + d2, where d1 is the distance between the robot arm and the substrate located above the robot arm when the substrate is carried in and out of the cassette. And d2 is a distance between the robot arm and the substrate located below the robot arm when the substrate is carried in and out of the cassette. 21. The substrate according to claim 20, wherein the area of the substrate is 12
0000 mm ² or more, the thickness of the substrate is 0.3 to 1.1 mm
A transfer machine, characterized in that: 22. A transfer machine according to claim 20, wherein each side of said substrate has a size of 300 × 400 mm or more, and said substrate has a thickness of 0.3 to 1.1 mm. 23. The substrate according to claim 20, wherein the area of said substrate is 12
0000 mm ² or more, and the thickness of the substrate is 0.4 to 0.8 mm
A transfer machine, characterized in that: 24. A transfer machine according to claim 20, wherein each side of said substrate has a size of 300 × 400 mm or more, and said substrate has a thickness of 0.4 to 0.8 mm. 25. The transfer machine according to claim 20, wherein the upper surface of the robot arm has a curvature convex toward the outside of the robot arm. 26. The transfer machine according to claim 20, wherein the lower surface of the robot arm has a curvature convex toward the outside of the robot arm. 27. The transfer machine according to claim 20, wherein the upper surface and the lower surface of the robot arm have a curvature that is convex toward the outside of the robot arm. 28. The cassette according to claim 20, wherein the projection holding the substrate of the cassette holds the substrate on a surface inclined from a horizontal plane, and the inclined surface is located at a center of the substrate. A transfer machine characterized in that the height of the transfer surface decreases. 29. The cassette according to claim 20, wherein a surface of the projection of the cassette, which holds the substrate, is located below the surface of the cassette that holds the substrate, and has a height toward the center of the substrate. A transfer machine characterized by an increasing surface. 30. The cassette according to claim 20, wherein the projection holding the substrate of the cassette holds the substrate on a surface 1 inclined from a horizontal plane, and the surface 1 is provided at the center of the substrate. The transfer machine according to claim 1, wherein the height decreases toward the center, and the surface (2) of the protrusion located below the surface (1) increases toward the center of the substrate. 31. A method for transporting a substrate via a robot arm from a cassette 1 in which a plurality of substrates are stored in a vertical direction to a cassette 2 in which a plurality of substrates are stored in a vertical direction. A distance d3 between adjacent substrates among the plurality of substrates, a distance d between smaller ones of distances d4 between adjacent substrates among the plurality of substrates stored in the cassette 1, and The larger of the thickness t3 of the robot arm, the warp t1 of the substrate generated when the substrate is held by the robot arm, and the warp generated in the substrate stored in the cassette 1 or the cassette 2. The relationship with t2 is conditional expression t1 + t2 + d
1 + d2>d> t3 + d1 + d2, and d1 is the distance between the robot arm and the substrate located above the robot arm when the substrate is loaded or unloaded in the cassette 1 or the cassette 2. D2 is a distance between the robot arm and the substrate located below the robot arm when loading or unloading a substrate in the cassette 1 or the cassette 2; A substrate transfer method, wherein substrates carried out from 1 by the robot arm are carried out in order from the top, and substrates carried in the cassette 2 by the robot arm are carried in in order from the bottom. 32. A method for transferring substrates via a robot arm from a cassette 1 in which a plurality of substrates are stored in a vertical direction to a cassette 2 in which a plurality of substrates are stored in a vertical direction. The distance d3 between adjacent substrates among the plurality of substrates and the distance between adjacent substrates among the plurality of substrates accommodated in the cassette 1 is defined as the distance d between the larger one of the substrates d4, The larger of the thickness t3 of the robot arm, the warp t1 of the substrate generated when the substrate is held by the robot arm, and the warp generated in the substrate stored in the cassette 1 or the cassette 2. The relationship with t2 is conditional expression t1 + t2 + d
1 + d2>d> t3 + d1 + d2, and d1 is the distance between the robot arm and the substrate located above the robot arm when the substrate is loaded or unloaded in the cassette 1 or the cassette 2. D2 is a distance between the robot arm and the substrate located below the robot arm when loading or unloading a substrate in the cassette 1 or the cassette 2; A substrate transfer method, wherein substrates carried out from 1 by the robot arm are carried out in order from the top, and substrates carried in the cassette 2 by the robot arm are carried in in order from the bottom. 33. A method of transferring a substrate using means having a cassette in which a plurality of substrates are stored in a vertical direction and a robot arm for transferring the substrates, wherein the method comprises the steps of: Where d is the distance between adjacent substrates
And the thickness t3 of the robot arm, and the warpage of the substrate caused when the substrate is held by the robot arm.
t1 and the warpage generated on the substrate stored in the cassette
The relationship with t2 is determined by the conditional expression t1 + t2 + d1 + d2>d> t3 + d1 +
d2 is satisfied, and d1 is the distance between the robot arm and the substrate located above the robot arm when the substrate is carried into and out of the cassette, and d2 is the distance between the substrate and the substrate. A distance between the robot arm and the substrate located below the robot arm when carrying in and out, and a step of carrying in the plurality of substrates sequentially from below the cassette by the robot arm. A method for transporting a substrate, comprising: 34. A method for transferring a substrate using means having a cassette in which a plurality of substrates are stored in a vertical direction and a robot arm for transferring the substrates, wherein the method comprises the steps of: Where d is the distance between adjacent substrates
And the thickness t3 of the robot arm, and the warpage of the substrate caused when the substrate is held by the robot arm.
t1 and the warpage generated on the substrate stored in the cassette
The relationship with t2 is determined by the conditional expression t1 + t2 + d1 + d2>d> t3 + d1 +
d2 is satisfied, and d1 is the distance between the robot arm and the substrate located above the robot arm when the substrate is carried into and out of the cassette, and d2 is the distance between the substrate and the substrate. A distance between the robot arm and the substrate located below the robot arm when carrying in and out, and a step of sequentially carrying out the plurality of substrates from above the cassette by the robot arm. Characteristic substrate transfer method.