This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2017-053313, filed on Mar. 17, 2017, the entire contents of which are incorporated herein by reference.
Embodiments described herein relate generally to a collimator and a processing apparatus.
Conventionally, processing apparatuses such as sputtering apparatuses including collimators have been known.
It is beneficial to provide a collimator and a processing apparatus having novel structures with less inconvenience which can reduce variation in film thickness depending on positions on an object to process, for example.
In general, according to one embodiment, a collimator includes a first face, a second face, a peripheral frame, a grid region, and first end walls. The first face intersects with a first direction. The second face is opposite to the first face, and intersects with the first direction. The grid region is a region in which unit frames are arranged along the first face and the second face between both ends of the peripheral frame in a second direction intersecting with the first direction. The unit frames surround unit through-holes penetrating through the collimator in the first direction. First end walls are positioned at both ends of the grid region in a third direction intersecting with the first direction and the second direction. The first end walls connect both ends of the grid region in the second direction. The grid region and the peripheral frame are provided with peripheral openings in-therebetween, and the peripheral openings are larger in size than the unit through-holes and penetrate through the collimator in the first direction. The peripheral openings include first peripheral openings located between the first end walls and the peripheral frame.
Exemplary embodiments of a collimator and a processing apparatus will now be disclosed. Configurations and control (technical features) of the embodiments provided below and operations and results (effects) produced by the configurations and control are only exemplary. In the drawings, directions V1, H2, and H3 are defined for the purpose of illustration. The direction V1 is a vertical direction (gravity direction), and the directions H2 and H3 are horizontal directions. The directions V1, H2, and H3 are perpendicular to one another.
The following embodiments include same or similar components. These components will be represented by the common reference numerals and redundant description thereof may be omitted below.
The sputtering apparatus 1 includes a chamber 11. The chamber 11 has a substantially cylindrical shape around a central axis along the direction V1, and has a top wall 11a, a bottom wall 11b, and a circumferential wall 11c (side wall). The top wall 11a and the bottom wall 11b stand perpendicular to the direction V1 and extend in the directions H2 and H3. A generatrix of the circumferential wall 11c is along the direction V1. The chamber 11 defines a substantially cylindrical space as a processing chamber R. The sputtering apparatus 1 is installed with the central axis (the direction V1) of the chamber 11 extending in the vertical direction. The chamber 11 is an example of a container.
A target T can be placed on the top wall 11a in the processing chamber R of the sputtering apparatus 1. The target T is supported by the top wall 11a through a backing plate, for example. The target T generates metal particles. The target T can be referred to as a particle emitter or a particle generator. The top wall 11a or the backing plate can be referred to as an emitter mount.
A magnet M can be placed on the top wall 11a outside the processing chamber R of the sputtering apparatus 1. The target T generates metal particles from a region near the magnet M.
A stage 12 is provided near the bottom wall 11b in the processing chamber R of the sputtering apparatus 1. The stage 12 supports the wafer W. The stage 12 includes a plate 12a, a shaft 12b, and a support 12c. The plate 12a has a disc shape having a face 12d perpendicular to the direction V1, for example. The plate 12a supports the wafer W on the face 12d such that a face wa of the wafer W is along a plane perpendicular to the direction V1. The shaft 12b protrudes from the support 12c in a direction opposite to the direction V1, and is connected to the plate 12a. The plate 12a is supported by the support 12c through the shaft 12b. The support 12c can change the position of the shaft 12b in the direction V1. For changing the position in the direction V1, the support 12c may include a mechanism capable of changing a fixing position (holding position) of the shaft 12b or may include an actuator including a motor or a rotation to linear motion converting mechanism capable of electrically changing the position of the shaft 12b in the direction V1. A change in the position of the shaft 12b in the direction V1 results in a change in the position of the plate 12a in the direction V1. The positions of the shaft 12b and the plate 12a can be set in multiple steps or in a non-step manner (continuously variable). The stage 12 (plate 12a) is an example of an object mount. The stage 12 can be referred to as an object support, a position changer, or a position adjuster.
A collimator 130 is disposed between the top wall 11a and the stage 12. The collimator 130 is supported by the circumferential wall 11c of the chamber 11. The collimator 130 has a substantially disc shape having an upper face 13a, a lower face 13b opposite to the upper face 13a, and a cylindrical circumferential wall 13f. The upper face 13a and the lower face 13b are perpendicular to the direction V1, and extends two-dimensionally in the directions H2 and H3. The thickness direction of the collimator 130 corresponds to the direction V1. The collimator 130 is placed in the chamber 11 with substantially no gap between the outer circumference of the circumferential wall 13f and the inner circumference of the circumferential wall 11c of the chamber 11. The upper face 13a is an example of a first face, and the lower face 13b is an example of a second face. The direction V1 is an example of a first direction. The circumferential wall 13f is an example of a peripheral frame and an edge.
The collimator 130 has a plurality of through-holes 13c extending between the upper face 13a and the lower face 13b in the direction V1. The through-holes 13c are open toward the target T, that is, toward the top wall 11a and also open toward the wafer W, that is, toward the stage 12, and extend in the direction V1.
As illustrated in
Meanwhile, the openings 13A extend between end walls 13e3 and 13e4 of the grid region 13L in the direction H3 and ends 13f3 and 13f4 of the collimator 131 in the direction H3, respectively. The end walls 13e3 and 13e4 connect the ends 13f1 and 13f2 (both ends), and extend straight in the direction H2 along the sides of the unit frames 13U. The openings 13A are located adjacent to the end walls 13e3 and 13e4 of the grid region 13L outside the grid region 13L, and extend in the direction H2. In addition, the openings 13A are larger in size than the through-holes 13c, extending between ends 13e1 and 13e2 (one end and the other end) of the respective end walls 13e3 and 13e4 in the direction H2. The openings 13A are an example of first peripheral openings (peripheral openings). The direction H2 is an example of a second direction, and the direction H3 is an example of a third direction.
The flow of particles is straightened in the direction V1 through the through-holes 13c extending in the direction V1 as described above. The collimator 130 is thus referred to as a flow straightener or a flow straightening member. The grid region 13L having the through-holes 13c can be referred to as a flow straightening part.
The circumferential wall 11c, for example, of the chamber 11 is provided with an outlet 11d. A pipe (not illustrated) extends from the outlet 11d and connects to a suction pump (vacuum pump; not illustrated), for example. By the operation of the suction pump, gas is discharged from the processing chamber R through the outlet 11d, which lowers the pressure in the processing chamber R. The suction pump is capable of sucking gas until the processing chamber R is placed substantially in a vacuum state.
The circumferential wall 11c, for example, of the chamber 11 is provided with an inlet 11e. A pipe (not illustrated) extends from the inlet 11e and connects to a tank (not illustrated), for example. The tank contains inert gas such as argon gas, for example. The inert gas in the tank can be introduced into the processing chamber R.
The circumferential wall 11c, for example, of the chamber 11 includes a transparent window 11f. The collimator 130 can be captured through the window 11f by a camera 20 installed outside of the chamber 11. The condition of the collimator 130 can be checked from the images captured by the camera 20 through image processing. The transparent window 11f may be covered with a detachable or openable lid, cover, or door. In addition, the circumferential wall 11c may have an opening (a through-hole) instead of the transparent window 11f, and may be provided with a lid that can open or close the opening. The lid, the cover, or the door can cover the window 11f or the opening during operation of the sputtering apparatus 1 and open the window 11f or the opening during non-operation of the sputtering apparatus 1, for example.
The sputtering apparatus 1 having the above structure ionizes the argon gas introduced into the processing chamber R by applying voltage to the target T, which generates plasma. The argon ions collide with the target T, which causes particles of a metal material (a film material) of the target T to fly from a bottom face ta of the target T, for example. The target T emits particles in this manner.
The flying directions of the particles from the bottom face ta of the target T are distributed according to the cosine law (Lambert's cosine law). Specifically, the particles flying from a certain point on the bottom face ta of the target T fly most in the normal direction (vertical direction or direction V1) to the bottom face ta. Thus, the normal direction is an example of the direction in which the target T placed on the top wall 11a or the backing plate (emitter mount) emits at least one particle. The number of particles flying in a direction at an angle θ with respect to (intersecting at an angle with) the normal direction is approximately proportional to a cosine (cos θ) of the number of particles flying in the normal direction.
The particles are microparticles of the metal material of the target T. The particles may be particles of matter such as molecules, atoms, atomic nuclei, elementary particles, or vapor (vaporized material). The particles may include positive ions such as positively charged copper ions.
As illustrated in
In the present embodiment, the collimator 131 (130) are thus provided with the openings 13A at both ends in the direction H3. Without the vertical walls 13d of the unit frames 13U in the openings 13A, a larger number of particles can reach the point Pe than with the vertical walls 13d in the openings 13A. Thus, by such a structure, the film at the ends (peripheries) of the wafer W can be made in larger thickness than that in related art, which prevents an increase in variation in the film thickness depending on the positions on the wafer W.
As described above, in the present embodiment, the openings 13A (first peripheral openings) of the collimator 131 (130) are located adjacent to the end walls 13e3 and 13e4 (first end walls) of the grid region 13L outside the grid region 13L, extend between the ends 13e1 and 13e2 (one end and the other end) of the end walls 13e3 and 13e4 in the direction H2 (second direction) along the end walls 13e3 and 13e4 in the direction H2, are larger in size than the through-holes 13c (unit through-holes), and penetrate through the collimator 131 in the direction V1. Thus, the openings 13A face the end walls 13e3 and 13e4 from the ends 13e1 (one end) to the ends 13e2 (the other end). This can prevent the film on the wafer W from becoming thinner in thickness at the point Pe on the end than at the center, leading to preventing an increase in variation in the film thickness depending on the positions on the wafer W.
In the present embodiment, the grid region 13L extends across the collimator 131 between the ends 13f1 and 13f2 (both ends) in the direction H2, and is relatively firmly supported by the ends 13f1 and 13f2 of the circumferential wall 13f with a desired width. Furthermore, the grid region 13L is connected to the circumferential wall 13f via the vertical walls 13d, which are shorter than the sides of the unit frames 13U and define the end through-holes 13c1 smaller than the through-holes 13c. As structured above, the grid region 13L can ensure desired rigidity and strength and desired position and orientation.
In addition, in the present embodiment, the through-holes 13c (unit through-holes) and the unit frames 13U have a quadrangular shape (polygonal shape) as viewed in the direction V1 (first direction). This makes it possible to provide the grid region 13L and the collimator 131 with simpler structures, and ensure desired rigidity and strength and thus desired position and orientation of the grid region 13L.
In the present embodiment as well, the grid region 13L extends across the collimator 132 between the ends 13f1 and 13f2 (both ends) in the direction H2.
The openings 13A extend between the end walls 13e3 and 13e4 of the grid region 13L in the direction H3 and the ends 13f3 and 13f4 of the collimator 132 in the direction H3, respectively. The end walls 13e3 and 13e4 each extend in the direction H2 along the sides of the hexagonal unit frames 13U in a zigzag manner.
Thus, in the present embodiment as well, the openings 13A (first peripheral openings) of the collimator 132 (130) are located adjacent to the end walls 13e3 and 13e4 (first end walls) of the grid region 13L outside the grid region 13L, extend between the ends 13e1 and 13e2 (one end and the other end) of the end walls 13e3 and 13e4 in the direction H2 (second direction) along the end walls 13e3 and 13e4 in the direction H2, are larger in size than the through-holes 13c (unit through-holes), and penetrate through the collimator 132 in the direction V1. Thus, the openings 13A face the end walls 13e3 and 13e4 from the ends 13e1 (one end) to the ends 13e2 (the other end). This can prevent the film from becoming thinner in thickness at the ends of the wafer W than at the center of the wafer W, and thus prevent an increase in variation in the film thickness depending on the positions on the wafer W.
In the present embodiment as well, the grid region 13L extends across the collimator 132 between the ends 13f1 and 13f2 (both ends) in the direction H2, and is relatively firmly supported by the ends 13f1 and 13f2 of the circumferential wall 13f with a desired width. The through-holes 13c (unit through-holes) and the unit frames 13U have a hexagonal shape. This makes it possible to provide the grid region 13L and the collimator 132 with simpler structures, and ensure desired rigidity and strength and thus desired position and orientation of the grid region 13L.
In the present embodiment as well, the grid region 13L extends across the collimator 133 between the ends 13f1 and 13f2 (both ends) in the direction H2.
In addition, the openings 13A extend between the end walls 13e3 and 13e4 of the grid region 13L in the direction H3 and the ends 13f3 and 13f4 of the collimator 133 in the direction H3, respectively. The end walls 13e3 and 13e4 extend straight in the direction H2 along the sides of the unit frames 13U.
Thus, in the present embodiment as well, the openings 13A (first peripheral openings) of the collimator 133 (130) are located adjacent to the end walls 13e3 and 13e4 (first end walls) of the grid region 13L outside the grid region 13L, extend between the ends 13e1 and 13e2 (one end and the other end) of the end walls 13e3 and 13e4 in the direction H2 (second direction) along the end walls 13e3 and 13e4 in the direction H2, are larger in size than the through-holes 13c (unit through-holes), and penetrate through the collimator 133 in the direction V1. This can prevent the film from becoming thinner in thickness at the ends of the wafer W than at the center of the wafer W, and thus prevent an increase in variation in the film thickness depending on the positions on the wafer W.
In addition, in the present embodiment as well, the grid region 13L extends across the collimator 133 between the ends 13f1 and 13f2 (both ends) in the direction H2, and is relatively securely supported by the ends 13f1 and 13f2 of the circumferential wall 13f with a desired width. The through-holes 13c (unit through-holes) and the unit frames 13U have a triangular shape. This makes it possible to provide the grid region 13L and the collimator 133 with simpler structures, and ensure desired rigidity and strength and desired position and orientation of the grid region 13L.
In the present embodiment, however, the collimator 133 is provided with openings 13B extending between end walls 13g3 and 13g4 of the grid region 13L in the direction H2 and the ends 13f1 and 13f2 of the collimator 134 in the direction H2, respectively, in addition to the openings 13A in the first embodiment. The end walls 13g3 and 13g4 connect the ends 13f3 and 13f4 (both ends) of the collimator 134 in the direction H3, and extend straight in the direction H3 along the sides of the unit frames 13U. The openings 13B are an example of second peripheral openings (peripheral openings), and the end walls 13g3 and 13g4 are an example of second end walls. In the present embodiment as well, the grid region 13L is connected at the ends (corners or four corners) to the circumferential wall 13f via relatively short vertical walls 13d defining the end through-holes 13c1, which are smaller than the through-holes 13c. Thereby, the grid region 13L can ensure desired rigidity and strength.
In the present embodiment, the collimator 134 (130) is provided with the openings 13B (second peripheral openings) in addition to the openings 13A. The openings 13B are located adjacent to the end walls 13g3 and 13g4 (second end walls) of the grid region 13L outside the grid region 13L, extend between ends 13g1 and 13g2 (one end and the other end) of the end walls 13g3 and 13g4 in the direction H3 (third direction) along the end walls 13g3 and 13g4 in the direction H3, are larger in size than the through-holes 13c (unit through-holes), and penetrate through the collimator 134 in the direction V1. Thus, the openings 13B face the end walls 13g3 and 13g4 from the ends 13g1 (one end) to the ends 13g2 (the other end). This can prevent the film from becoming thinner in thickness at the end of the wafer W than at the center of the wafer W, and thus prevent an increase in variation in the film thickness depending on the positions on the wafer W. In addition, the area of the film having a thinner thickness than the rest of the film can be made smaller than that in the first to third embodiments. The shape of the through-holes 13c and the unit frames 13U of the collimator 134 having such openings 13B is not limited to being quadrangular but may be triangular or hexagonal, for example.
Modifications
In the modification of
In the modifications of
The collimators 137 and 138 both include end regions 13E between the grid region 13L and the arc-like circumferential walls 13f facing the circumferential wall 11c of the chamber 11. The end regions 13E include the end frames 13d1 surrounding the end through-holes 13c1. The end through-holes 13c1 are different in size (cross-sectional area or opening area) from the through-holes 13c (unit through-holes) and can be larger or smaller than the through-holes 13c. In
In these modifications, the circumferential wall 13f or the end regions 13E are supported by the circumferential wall 11c of the chamber 11. As is clear in
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions. The configurations and forms of the embodiments can be partially replaced with each other. Furthermore, specifications including configurations and forms (structures, types, directions, shapes, sizes, lengths, widths, thicknesses, angles, numbers, positions, materials, and the like) can be changed as necessary. For example, the processing apparatus may be an apparatus such as a CVD apparatus other than the sputtering apparatus. In addition, the unit through-holes and the unit frames may have shapes other than those in the embodiments described above.
Number | Date | Country | Kind |
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2017-053313 | Mar 2017 | JP | national |