JP2006019566A - Semiconductor substrate adsorption hand and its operation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor substrate adsorption hand and its operation method for surely adsorbing a semiconductor substrate even when the semiconductor substrate is largely scaled and made thin, and the surface is bent, and for easily setting the semiconductor substrate on an adsorption stage for treating it, and for extremely reducing the surface contamination of the semiconductor substrate. <P>SOLUTION: This semiconductor substrate adsorption hand is provided with a chuck 10 supported by an arm 1 for holding a semiconductor substrate 15, and a substrate adsorber 11 arranged at the central part of the chuck for carrying out the vacuum adsorption of the semiconductor substrate and a plurality of pins 8 arranged at the periphery of the chuck for suppressing the periphery of the semiconductor substrate. A plurality of projections whose top end diameters are smaller than those of other parts are planted in the substrate adsorber, and configured so that those top ends can be brought into contact with the semiconductor substrate when the semiconductor substrate is adsorbed. Thus, the semiconductor substrate can be adsorbed while being corrected to a plane shape by using the hand. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  In semiconductor manufacturing technology, the present invention relates to a semiconductor substrate suction hand that holds a wafer (semiconductor substrate) and transfers it to a predetermined position in order to process it.

A semiconductor substrate is formed into a wafer by slicing an ingot obtained by crystal growth, and a semiconductor element in which an integrated circuit or the like is formed is formed there. In order to form such a semiconductor element, a wafer (hereinafter referred to as a semiconductor substrate) is transported to a processing stage (suction stage) for element formation by a semiconductor substrate suction hand and placed thereon.
A conventional semiconductor substrate suction hand includes two or more vacuum pads for holding a semiconductor substrate by vacuum suction. The semiconductor substrate is placed at a predetermined position of the suction stage while being held by the vacuum pad. The placed semiconductor substrate is evacuated and held and fixed on the suction stage until the end of processing.
In recent years, the diameter of a wafer-like semiconductor substrate has been increased and the thickness has been reduced to about 50 μm, and as a result, the warpage of the semiconductor substrate has increased, and the above-described conventional technology has increased conveyance troubles and cannot be conveyed. Also occurs. If the diameter of the wafer is about 4 or 5 inches, even if it is thin, there is no problem that warpage occurs and the wafer cannot be sucked by the semiconductor substrate suction hand. However, if the diameter of the wafer becomes large, such as 8 inches, and the thickness becomes thin as described above, a problem occurs in the suction force and the conveyance becomes difficult.

Thus, when the semiconductor substrate is warped, the peripheral portion may be lowered and warped upward, or the peripheral portion may be raised and warped downward (see FIG. 4). Usually, since the semiconductor substrate is in a flat state, the suction force of the vacuum pad does not change. However, if the semiconductor substrate is warped up or down, the vacuum pad does not contact the flat surface accurately, and thus the suction force decreases. In severe cases, when the warpage of the semiconductor substrate increases, it may not be adsorbed by the vacuum pad. When the semiconductor substrate is set on the suction stage in a warped state, the semiconductor substrate may be warped and may not be sucked. In addition, the vacuum pad that adsorbs the semiconductor substrate uses an elastic body such as rubber. However, if the surface of the semiconductor substrate is adsorbed with such a soft material, the vacuum pad mark is attached to the surface of the semiconductor substrate, causing contamination. (Patent Document 1).
JP 2003-303873 A

  The present invention has been made under such circumstances, and can be reliably adsorbed even when the semiconductor substrate becomes large and thin and the surface is warped, and is set in an adsorption stage for processing the semiconductor substrate. The present invention provides a semiconductor substrate suction hand that can be easily performed and can significantly reduce surface contamination of a semiconductor substrate and a method of operating the same.

In order to solve such a problem, one aspect of the semiconductor substrate suction hand of the present invention includes a chuck that is supported by an arm and holds the semiconductor substrate, and a suction that is provided in the chuck central portion and vacuum-sucks the semiconductor substrate. And a plurality of pins provided at the chuck peripheral portion for suppressing the peripheral portion of the semiconductor substrate, and a plurality of protrusions having a tip portion with a smaller diameter than the other portions are implanted in the suction portion, When adsorbing the semiconductor substrate, the tip portion is configured to come into contact with the semiconductor substrate.
According to another aspect of the method of operating the semiconductor substrate suction hand of the present invention, when the semiconductor substrate warped using the semiconductor substrate suction hand is operated, the semiconductor substrate is planarized using the pins and the suction portion. It is characterized by adsorbing while correcting the shape.

  The present invention can accurately suck and maintain a warped semiconductor substrate and reliably suck the semiconductor substrate warped by the suction stage. Further, when the warped semiconductor substrate is adsorbed, it can be transferred without contaminating the surface.

The present invention is characterized in that the semiconductor substrate warped is maintained by suction, and the semiconductor substrate warped by the suction stage is suctioned while being corrected to a flat shape. Also, when adsorbing the surface of the semiconductor substrate, the contact area is made as small as possible, and parts that come in contact with the surface of the semiconductor substrate can be transported without contaminating the semiconductor substrate by using a material with the same hardness as the semiconductor substrate. It is characterized by doing.
Hereinafter, the best mode for carrying out the invention will be described with reference to examples.

First, Embodiment 1 will be described with reference to FIGS.
FIG. 1 is a cross-sectional view showing the main part of a semiconductor substrate suction hand according to Embodiment 1 of the present invention, and FIG. 2 is a plan view of the suction part constituting the semiconductor substrate suction hand shown in FIG. FIG. 3 is a partial cross-sectional view showing the main part of the semiconductor substrate suction hand shown in FIG. 1 holding the semiconductor substrate and the suction stage for wafer processing thereon, FIG. These are the fragmentary sectional views which show the principal part of the adsorption | suction stage which stocks the semiconductor substrate adsorption | suction hand shown in FIG. 1 holding the semiconductor substrate, and the semiconductor substrate on it.

  FIG. 1 shows the main part of a semiconductor substrate suction hand. The semiconductor substrate is held by a chuck 10 attached to the tip of the arm 1 and conveyed to a predetermined position. The arm 1 is connected to a vertical movement drive unit (not shown), and a guide 4 is fitted to the tip. The guide 4 is fixed to the arm 1 by a bolt 2. The chuck 10 has a vertically protruding portion at the center portion, the lower protruding portion includes a ring-shaped substrate suction portion 11, and the upper protruding portion is fitted to the guide 4. The guide 4 suppresses the periphery of the protruding portion above the central portion of the chuck 10 and guides when moving up and down. The protruding portion on the chuck 10 is composed of a large diameter portion 10a at the base portion and a small diameter portion 10b at the tip portion. The guide 4 is fitted to the large diameter portion 10a and the small diameter portion 10b. The large diameter portion 10 a of the chuck 10 is fixed to the guide 4 by the pin 7 via the slide bearing 5, and the guide 4 and the chuck 10 are fixed by the collar 3. When the guide 4 is fitted to the large-diameter portion 10a and the small-diameter portion 10b, there is a space between the small-diameter portion 10b and the guide 4, and the spring 6 is accommodated therein. The spring 6 applies a certain force to the semiconductor substrate when the chuck 10 presses and adsorbs the semiconductor substrate. The force applied to the semiconductor substrate is suitably 200 g to 600 g, for example, 500 g.

  A pin 8, which is a feature of the present invention, is attached to the periphery of the chuck 10 and is fixed by a nut 9. Three to four or more pins 8 are attached. The pin 8 is arranged so that the tip of the chuck 8 faces the side where the substrate adsorption portion 11 for adsorbing the semiconductor substrate of the chuck 10 is formed, and suppresses the peripheral portion of the semiconductor substrate to correct the warp.

  A substrate suction portion 11 is attached to the protruding portion below the chuck 10. The substrate adsorbing portion 11 has a ring shape, and a plurality of protrusions 12 having a tip diameter smaller than other portions are implanted in a sword mountain shape, and the tip portion contacts the semiconductor substrate when adsorbing the semiconductor substrate. It is configured as follows. The portion of the protrusion 12 that contacts the semiconductor substrate is preferably 0.3 mm or less, for example, 0.2 mm. With such a size, dust of 0.3 mm or more on the semiconductor substrate can be avoided. Moreover, the diameter of another part is 1.5 mm, for example (refer FIG. 2). An air vent hole 13 is formed in the central portion of the substrate suction portion 11 for evacuating the substrate suction portion 11. The air vent hole 13 communicates with the inside of the arm 1 connected to an exhaust pump (not shown) through the upper and lower protrusions of the chuck 10. The diameter of the ring-shaped substrate suction part 11 is, for example, 20 mm to 30 mm. If the substrate adsorption part diameter is 20 mm, a wafer (semiconductor substrate) of 5 inches or more can be adsorbed (adsorption power is about 500 mmHg), and if the substrate adsorption part diameter is 30 mm, a wafer (semiconductor substrate) of 8 inches or more is adsorbed. can do.

  Next, a method for transporting a semiconductor substrate using a semiconductor substrate suction hand will be described with reference to FIGS. The suction stage (2) shown in FIG. 4 is a table for temporarily holding a wafer (semiconductor substrate) cut out from an ingot, and sucks and holds the semiconductor substrate by vacuuming. The suction stage (1) shown in FIG. 3 is a processing stage that performs processing such as element formation on a semiconductor substrate.

  The semiconductor substrate 15 held on the adsorption stage (2) 17 is adsorbed by the substrate adsorption unit 11 of the chuck 10 supported by the arm 1 descending from above and transferred to the adsorption stage (1). Due to the presence of the pins 8 around the chuck 10, the semiconductor substrate 15 is stably held and transported regardless of whether the semiconductor substrate 15 is warped upward or downward. The chuck 10 holding the semiconductor substrate 15 is lowered by the arm 1 from above the suction surface of the suction stage (1) 16 as a processing table. For example, when the semiconductor substrate 15 warped downward is placed on the suction stage (1) 16 as shown in FIG. 3, the chuck 10 is lowered by a drive source that drives the arm 1. The chuck 10 continues to descend after a part of the semiconductor substrate 15 comes into contact with the suction stage (1) 16, and the semiconductor substrate 15 is moved to the suction stage (1) 16 while the pins 8 correct the semiconductor substrate 15 into a flat shape. Place. The suction stage (1) vacuums (vacuums) the suction surface 16a to hold the semiconductor substrate 15 by suction. In this manner, when placing (setting) a semiconductor substrate warped downward on the suction stage, the semiconductor substrate is placed stably so as to be placed while being corrected to a flat shape.

Further, for example, when a semiconductor substrate warped upward as shown in FIG. 4 is placed on the suction stage (1), the chuck is lowered by a drive source for driving the arm. While descending, the peripheral portion of the semiconductor substrate warped upward is pushed downward by the pins, and therefore the entire surface of the semiconductor substrate is placed in contact with the suction stage (1) while being corrected to a flat shape. The suction stage (1) vacuums (vacuum) the suction surface and holds the semiconductor substrate warped in this way (see FIG. 3). In this way, when the semiconductor substrate warped upward is placed (set) on the suction stage (1), the semiconductor substrate is placed while being corrected to a flat shape, so that the semiconductor substrate is stably placed.
In this embodiment, in order to make the contact area with the semiconductor substrate as small as possible, the inside of the ring shape of the substrate adsorption portion is sword-shaped and the tip is tapered, so that the surface of the semiconductor substrate is contaminated. There are few things. In addition, the material that contacts the surface of the semiconductor substrate (for example, the chuck 10 and the pins 8 shown in FIG. 1) is a semiconductor that has less transfer by using a material such as silicon having a hardness equal to or higher than that of the semiconductor substrate. The contamination of the substrate can be reduced.

  Examples of such a material include PEEK and ceramic. PEEK is a plastic material of Victrex, and is a thermoplastic made of polyallyl ether ketone, peak-reether ether ketone, or the like. Since this material has approximately the same hardness as silicon, it is a part that does not cause contamination with little transfer.

Next, Example 2 will be described with reference to FIG.
In this embodiment, the positional relationship between a semiconductor substrate and pins for correcting the semiconductor substrate into a planar shape will be described. FIG. 5 is a plan view of a wafer-like semiconductor substrate, showing a state where pins of the semiconductor substrate suction hand are in contact.
The semiconductor substrate 15 held on the suction stage is sucked by the substrate suction portion at the center of the chuck supported by the arm descending from above and is transported to the suction stage. Due to the presence of the pins 8 attached to the periphery of the chuck, the semiconductor substrate 15 is stably held and transported regardless of whether the semiconductor substrate 15 is warped upward or downward. The chuck holding the semiconductor substrate 15 is lowered from above the suction surface of the suction stage, which is a processing table, by the arm. For example, when the semiconductor substrate 15 warped downward is placed on the suction stage as shown in FIG. 3, the chuck is lowered by a driving source for driving the arm.

  The lowering of the chuck continues after a part of the semiconductor substrate 15 comes into contact with the suction stage, and the pins 8 place the semiconductor substrate 15 on the suction stage while correcting the semiconductor substrate 15 into a flat shape. The suction stage sucks and holds the semiconductor substrate 15 by performing vacuuming (vacuum) on the suction surface. As described above, when the semiconductor substrate warped downward is set (set) on the suction stage, the semiconductor substrate is stably placed while being corrected to a flat shape. In order to place the semiconductor substrate in a stable manner while correcting it to a flat shape, for example, the pin 8 is configured to abut on the inner side of a certain distance a from the outermost periphery. The number of pins 8 is not limited to three shown in this embodiment. The number may be two, three, four, or more, and may be any number as long as the semiconductor substrate is stably placed while being corrected to a flat shape. The constant distance a is a distance at which the orientation flat 14 representing a flat portion that facilitates alignment and the like is formed. That is, the pins 8 are arranged so as to contact the inner side of the orientation flat 15a although they are the peripheral part of the semiconductor substrate. By arranging in this way, when setting the semiconductor substrate on the suction stage, it is possible to stably place the semiconductor substrate while correcting it to a flat shape, and it is stable while correcting the warped semiconductor substrate to a flat shape. Can be absorbed.

  With such a configuration, the semiconductor substrate suction hand according to the present invention can transport the warped semiconductor substrate, and when the semiconductor substrate is set on the suction stage, the semiconductor substrate is stably mounted while being corrected to a flat surface. Furthermore, it is possible to stably perform suction while correcting the warped semiconductor substrate into a flat shape. In addition, when the surface of the semiconductor substrate is adsorbed, the contact area is made as small as possible, and the parts in contact with the surface of the semiconductor substrate use a material having the same hardness as that of the semiconductor substrate without contaminating the surface of the semiconductor substrate. Transport can be performed.

Sectional drawing which shows the principal part of the semiconductor substrate adsorption | suction hand which concerns on Example 1 of this invention. The top view of the adsorption | suction part which comprises the semiconductor substrate adsorption | suction hand shown by FIG. 1, and sectional drawing of the part which follows the AA 'line of this top view. FIG. 2 is a partial cross-sectional view showing a main part of the semiconductor substrate suction hand shown in FIG. 1 holding a semiconductor substrate and a suction stage for wafer processing thereon; FIG. 2 is a partial cross-sectional view showing a main part of a suction stage for stocking a semiconductor substrate suction hand shown in FIG. 1 holding a semiconductor substrate and a semiconductor substrate thereon; The top view explaining the positional relationship of the semiconductor substrate which concerns on Example 2 of this invention, and the pin which corrects a semiconductor substrate in planar shape.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Arm 4 ... Guide 6 ... Spring 8 ... Pin 10 ... Chuck 11 ...- Substrate adsorption part 12 ... Protrusion 13 ... Air vent hole 14 ... Orientation flat 15 ...・ Semiconductor substrate 16, 17 ... Suction stage

Claims (5)

A chuck supported by the arm and holding the semiconductor substrate;
A substrate suction portion provided in the chuck central portion for vacuum suction of the semiconductor substrate;
A plurality of pins provided in the chuck peripheral portion and holding the peripheral portion of the semiconductor substrate;
The substrate suction portion is provided with a plurality of protrusions having a tip portion smaller in diameter than other portions, and configured to contact the semiconductor substrate when the semiconductor substrate is sucked. A semiconductor substrate suction hand characterized by comprising: The semiconductor substrate held by the chuck has an orientation flat, and the pin is arranged so as to contact the inside of the orientation flat, although it is a peripheral portion of the semiconductor substrate. 2. A semiconductor substrate suction hand according to 1. The semiconductor substrate suction hand according to claim 1, wherein the semiconductor substrate is suctioned to the substrate suction portion while being corrected to a flat shape. 4. The semiconductor substrate suction hand according to claim 1, wherein the hardness of the pin and the substrate suction portion is equal to or greater than the hardness of the semiconductor substrate. 5. 5. When operating a warped semiconductor substrate using the semiconductor substrate suction hand according to claim 1, the semiconductor substrate is corrected to a planar shape using the pins and the substrate suction portion. A method for operating a semiconductor substrate suction hand, wherein the suction is performed while suctioning.

Images