JP4287326B2 - Inner liner for semiconductor manufacturing apparatus and molding method thereof - Google Patents

Description

  The present invention relates to a cylindrical inner liner provided in a processing chamber in order to protect an inner wall exposed portion of the processing chamber of a semiconductor manufacturing apparatus, and a molding method thereof.

  In the manufacture of semiconductor devices, a semiconductor manufacturing apparatus is known in which a process gas introduced into a processing chamber is turned into plasma by a plasma generating means, and the plasmaized gas is reacted on the surface of a semiconductor wafer to perform fine processing. Such surface treatment of a semiconductor wafer is called plasma etching as dry etching. An inner liner is installed in the processing chamber of such a semiconductor manufacturing apparatus for the purpose of protecting the exposed portion of the processing chamber wall from plasma. The inner liner is usually made of an engineering plastics material such as polyimide or polyetherimide because it needs to have plasma resistance. These engineering plastics materials are generally expensive, have a higher hardness than other synthetic resins, and are difficult to handle because they are difficult to bond with an adhesive. Even if it can be bonded, impurities are brought into the processing chamber as the inner liner.

  Since the processing chamber is usually defined by the inner wall of the cylindrical wall, in order to mount the inner liner along the side wall of the processing chamber, the inner liner needs to be formed in a cylindrical structure. The inner liner is actually manufactured in a cylindrical structure by extrusion molding, machining or welding by machining. In such a manufacturing method, it is expensive to manufacture and machine a mold, and it is very expensive though it is a consumable part. In addition, it is difficult to secure sufficient strength with respect to the total thickness of the method by welding. It is conceivable to simply bend the belt-like plate into a cylindrical shape and abut the plate end, and use it in the processing chamber as it is without welding the plate end, but in this case, the abutted plate end is Since it floats without being in close contact with the inner wall of the processing chamber, there is a problem that the temperature rises due to the plasma at the abutting portion, and the consumption of the liner material becomes extremely fast, leading to an increase in running cost.

  FIG. 7 is a cross-sectional view showing an example of mounting an inner liner provided in a processing chamber of a semiconductor manufacturing apparatus. The structure of the semiconductor manufacturing apparatus shown in FIG. 7 is known, and the side wall 1 is made of a nonmagnetic metal material such as aluminum having good thermal conductivity in order to form a processing chamber therein. Inside the side wall 1, a replaceable side wall inner unit 2 in which a jacket for supplying a heat medium for temperature control is formed. Since the inside of the processing chamber 15 is in a plasma generation environment when the semiconductor manufacturing apparatus is in operation, the inner liner 3 is disposed inside the side wall inner unit 2 for the purpose of protecting the inner wall of the side wall inner unit 2 that is the exposed portion of the processing chamber wall from plasma. Is arranged. The inner liner 3 is made to stick to the side wall inner unit 2 in size, and the gap between the side wall inner unit 2 and the inner liner 3 is as narrow as possible (or the gap). Is considered). Since the inner liner 3 gradually decreases in thickness as it is exposed to plasma, it needs to be replenished as a consumable item.

  In the semiconductor manufacturing apparatus shown in FIG. 7, the antenna 5 for electromagnetic wave radiation includes a dielectric plate 7 and a plate 12 and is held by a housing 4 as a part of a vacuum container. A ring 6 is installed on the outer periphery of the plate 12 in contact with the plasma. The antenna 5 and the lower electrode 10 are installed so as to face each other in parallel. For example, when etching a silicon oxide film, the wafer W, which is an object to be processed, is placed and adsorbed on the lower electrode 10. If necessary, the height of the lower electrode 10 is adjusted to set a predetermined gap between the lower electrode 10 and the plasma generating means provided on the upper part. Next, the inside of the processing chamber 15 is evacuated by an evacuation system (not shown). On the other hand, the processing gas, for example, C4F8 and Ar necessary for the etching process of the sample W is controlled to a predetermined distribution from the gas supply means 11 through a large number of holes provided in the plate 12 of the antenna 5 at a predetermined flow rate and mixing ratio. And supplied to the processing chamber 15. At the same time, the processing chamber 15 is evacuated by a vacuum exhaust system and adjusted to a predetermined processing pressure, for example, 1 Pa. On the other hand, a magnetic field having a predetermined distribution and strength is formed by magnetic field forming means (consisting of an electromagnetic coil and a yoke, not shown) disposed outside the side wall 1. UHF band electromagnetic waves are radiated from the antenna 5 by the antenna power source 8, and plasma is generated in the processing chamber 15 by interaction with the magnetic field. By this plasma, the processing gas is dissociated to generate ions and radicals, and the bias power source 9 is controlled to perform processing such as etching on the wafer We. With the completion of the etching process, the supply of power and processing gas is stopped and the etching is terminated.

  FIG. 8 is a schematic perspective view showing an example of the shape of a conventional inner liner. The inner liner 3 is formed in a cylindrical shape, has a width that covers the plasma exposure portion of the side wall inner unit 2, and has a diameter D that matches the inner diameter of the side wall inner unit 2. The inner liner 3 is formed in a cylindrical shape by curving a belt-like plate into a cylindrical shape and welding the two end portions together to form a weld joint 13. In the illustrated example, the welding joint 13 is formed at one place on the circumference, but a plurality of places can be provided.

  9 and 10 are partial views showing a conventional welded joint structure applied to the end portion of the inner liner. FIG. 9 is a side view showing an example of a conventional welded joint structure for the inner liner. A liner material made of an engineering plastic material such as polyimide is generally welded by frictional melting by ultrasonic vibration. In the inner liner 3A shown in FIG. 9, both end portions 21 and 22 of the belt-like plate, which is a liner material, are formed in a complementary shape by being cut into steps that are half the plate thickness within a range corresponding to the welding width Bw. The inner liner 3A has mating surfaces 23 and 24 in the vicinity of the center of the plate thickness, and the axial width W in the direction of the arrow with the welding width Bw from the inside and outside of the cylinder in a state where both end portions 21 and 22 are engaged with each other (FIG. 8). By applying pressure over the entire width and applying ultrasonic vibration, the mating surfaces 23 and 24 are friction-melted and welded. In this welded joint 13A, the portions that are perpendicular to the plate thickness T remain as unwelded portions between the mating end surfaces and cutouts 27 and 28 are generated. The welded joint 13A having the notches 27 and 28 is unstable in strength, and there is a risk of stress concentration when it is made into a cylindrical shape and cracking. Further, when the inner liner 3A is gradually thinned as it is consumed, the end portions 21 and 22 are separated and cannot maintain a true cylindrical shape when the inner liner 3A is consumed to half of the total thickness T. There is a problem that it is time consuming and uneconomical.

  FIG. 10 is a side view showing another example of a conventional welded joint structure for an inner liner. In the welded joint 13B shown in FIG. 10, the mating surfaces 29 and 30 are formed so as to incline complementarily with respect to the radial direction of the inner liner 3B. That is, the mating surfaces 29 and 30 are flat surfaces including the generatrix of the inner and outer cylindrical surfaces of the inner liner 3B, but are formed as inclined surfaces that are inclined at an angle θ in the radial direction. In this example, since the mating surfaces 29 and 30 are welded over the entire plate thickness T, the inner liner 3B can be used economically compared to the example shown in FIG. it can. Within the welding width Bw, the protrusion 31 is provided over the entire width of the axial width W (FIG. 8) of the inner liner 3B at one place or a plurality of places (one place in this example) of the total thickness T. Therefore, when frictional melting is performed by ultrasonic vibration, there is an advantage that a portion where melting starts first is specified as the protrusion 31 and the mating surfaces 29 and 30 are easily melted. However, the formation of the protrusions 31 having a uniform height and shape over the entire axial width W is that the welding width Bw is narrow and the total plate thickness T is thin, even in the inclined mating surfaces 29 and 30. Combined with this, there is a problem that the processing takes a very long time and costs are increased.

  Therefore, it is easy to start welding while maintaining the advantage of using the total plate thickness and easily starting welding until the mating surfaces are formed to be inclined in a complementary manner with respect to the radial direction of the inner liner and consumed. There is a problem to be solved in terms of simplifying the structure.

  The object of the present invention is to form a die-shaped surface of the belt-like liner material with a complementary inclined surface, and weld it on the mating surface, so that it can be produced by extrusion molding, machining by machining, etc. Reducing the manufacturing cost of the inner liner by eliminating the need for machining and machining, and facilitating the processing of the protruding welding start area even with a liner material with a thin plate thickness, reducing the molding cost and increasing the reliability for welding An object of the present invention is to provide an inner liner for a semiconductor manufacturing apparatus that can be improved and a molding method thereof.

  In order to solve the above-described problems, an inner liner for a semiconductor manufacturing apparatus according to the present invention is for a cylindrical semiconductor manufacturing apparatus disposed in the processing chamber for the purpose of protecting a wall exposed portion of the processing chamber of the semiconductor manufacturing apparatus from plasma. Both ends of the inner liner, which are complementary inclined surfaces inclined with respect to the radial direction of the strip-shaped liner material curved in a cylindrical shape, are processed in the depth direction on at least one of the inclined surfaces. The plurality of convex portions left apart in the axial width direction of the cylindrical shape by being applied are welded on the two inclined surfaces as welding start regions.

  According to the inner liner for a semiconductor manufacturing apparatus, complementary inclined surfaces that are inclined in the radial direction are formed at both ends of the belt-shaped liner material that is curved into a cylindrical shape. When it is welded, it can be welded to the entire plate thickness. Therefore, by connecting both end portions by welding, it is possible to obtain a cylindrical inner liner that can use the entire thickness until consumption. Also, by processing at least one inclined surface in the depth direction, the plurality of convex portions remaining in the axial width direction of the cylindrical shape are used as welding start regions, and both inclined surfaces are welded, so the welding start regions are discrete. In this way, the weld spreads around it, so that both end portions of the liner material can be reliably welded over the entire width in the axial width direction and over the entire weld width of the mating surface.

  Also, the method for forming an inner liner for a semiconductor manufacturing apparatus according to the present invention forms complementary inclined surfaces radially inclined at both ends of a strip-shaped liner material curved in a cylindrical shape, and at least one of the inclined surfaces is formed. Forming a plurality of convex portions left spaced apart in the axial direction of the cylindrical shape by processing in the depth direction, and welding the both inclined surfaces with the convex portions as welding start regions, An inner liner that protects the exposed wall of the processing chamber of the semiconductor manufacturing apparatus from plasma is formed into a cylindrical shape.

  According to this method for forming an inner liner for a semiconductor manufacturing apparatus, a plurality of protrusions are left in the axial direction of the cylindrical shape by processing the inclined surface in the depth direction, and the plurality of protrusions are welded to the welding start region. As the two inclined surfaces are welded together, it is still difficult to perform fine processing even with a mating surface that is somewhat wider due to the inclined surfaces, but by forming a plurality of convex portions in the axial width direction, the welded joint portion This makes it easy to process the welding start area, and can reduce the molding cost of the inner liner.

In the inner liner for a semiconductor manufacturing apparatus and the molding method thereof, it is preferable that the convex portion is a regular saw blade convex portion formed in a saw-tooth shape. By forming the convex portion as the welding start region into a regular saw-tooth convex portion, the welding start region becomes a narrow convex portion regularly arranged at regular intervals, and the welding is uniformly and reliably performed in the entire region of the mating surfaces. It can be carried out. The Ru can be mechanically carried out easily and uniformly in the same manner as performed dressing processing of the saw of sawtooth protrusions to be welded initiation region in terms of molding.

In the inner liner for a semiconductor manufacturing apparatus and the molding method therefor, the both end portions can be provided with positioning means for determining the mutual positions in order to weld the inclined surfaces at correct positions. By providing positioning means for deciding each other's position at both ends of the liner material, both inclined surfaces are welded at the correct positions at the time of welding, and the manufactured inner liner becomes an inner liner that is correctly manufactured in a cylindrical shape. Further, even if the molding process, by positioning the positioning means a mutual position of the two end portions of the liner material, Ru can be welded to the inclined surfaces are in the correct position.

  In the inner liner for a semiconductor manufacturing apparatus and the molding method thereof, the liner material can be a resin material such as polyimide, polyetherimide, polybenzimidazole or the like. Such an engineering plastic used as a liner material is generally a material having a high hardness and is difficult to be molded. However, it can be molded into a cylindrical shape by welding at a welding start region.

  As described above, according to the inner liner for a semiconductor manufacturing apparatus and the molding method thereof according to the present invention, welding is performed on the entire plate thickness by overlapping and welding the inclined surfaces formed at both ends of the liner material. The cost can be reduced by eliminating the need for a mold or machining as compared with the case of manufacturing by extrusion molding or machining by machining. In addition, as a joint structure in which both ends are joined by welding, a plurality of convex portions remain in the axial width direction of a cylindrical shape such as a saw blade by processing the inclined surface of at least one end portion in the depth direction. In addition, it is possible to provide a reliable welded joint structure that facilitates the processing of the protrusions that are the welding start region even with a thin plate material, and that leads to cost reduction. In addition, by positioning pins and steps to position the inner liner circumference at the time of welding work on the welded joint, the diameter when the two ends of the belt-like liner material are welded into a cylindrical shape is manufactured by semiconductor manufacturing. It can be fitted to the processing chamber wall of the device.

  Embodiments of an inner liner for a semiconductor manufacturing apparatus and a molding method thereof according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a side view showing an embodiment of a welded joint structure for connecting both ends of an inner liner for a semiconductor manufacturing apparatus according to the present invention, and FIG. 2 is an enlarged view showing one end of the inner liner shown in FIG. .

  As shown in FIGS. 1 to 3, when manufacturing the inner liner, first, a belt-like liner material 40 made of a resin material having excellent heat resistance such as polyimide, polyetherimide, polybenzimidazole or the like is prepared. At both end portions 41 and 42 of the liner material 40 to be joined, complementary inclined surfaces 43 and 44 that are inclined at an angle θ with respect to the radial direction are formed as the joining surfaces to be welded. Next, the strip-shaped liner material 40 having both end portions 41 and 42 formed on the inclined surfaces 43 and 44 is curved into a cylindrical shape. By forming the inclined surfaces 43 and 44 in a complementary manner, the cylindrical inner and outer surfaces are smoothly formed without unevenness when the end portions 41 and 42 are overlapped and welded, and are applied as an inner liner to a semiconductor manufacturing apparatus. In this case, even when exposed to plasma, local high temperature and abnormal wear can be prevented. Further, by forming the inclined surfaces 43 and 44 in a complementary manner, the inner liner welds the inclined surfaces 43 and 44 over the entire plate thickness T. Therefore, the inner liner does not reach the wear limit in the middle of the thickness, and a cylindrical inner liner in which the entire plate thickness T can be used before the wear can be obtained.

  As shown in FIG. 2, a plurality of convex portions 45 are formed on the inclined surface 43 of one end portion 41 by processing in the depth direction at discrete positions over the entire axial width W. It is formed in the shape of a saw blade 46 that is left in a protruding shape. As the processing in the depth direction, for example, sharpening of a saw blade can be applied. By adopting such a processing method, the saw blade 46 has a length corresponding to the welding width Bw and a uniform height and a uniform height. It has a shape and is processed at a uniform pitch in the direction of the axial width W. Further, according to the sharpening process, it is possible to easily and easily perform the machining operation even if the axial width W becomes long. Since both the inclined surfaces 43 and 44 are welded using the plurality of convex portions 45 as welding start regions, the welding start regions are obtained discretely, and the welding spreads around the welding start regions as the welding operation proceeds, so that the liner material Both end portions of 40 can be reliably welded over the entire width of the axial width W and over the entire welding width Bw of the mating surfaces.

  In the example of the welded joint structure shown in the drawing, the saw blade 46 is formed only on one inclined surface 43 of the liner material 40, but a saw blade similar to the saw blade 46 may be formed on both inclined surfaces 43 and 44. it can. In this case, it is preferable to use positioning means as will be described later in order to prevent the saw blades from shifting from each other.

  As shown in the perspective view of FIG. 3, both inclined surfaces 43 and 44 are welded using the plurality of convex portions 45 as welding start regions, and an inner liner 47 is formed. Since a material such as polyimide is colored but nearly transparent, the welding start area can be visually distinguished from the subsequent welding area.

  FIG. 4 shows another example of the joint structure as a side view. As shown in FIG. 4, the saw blade 48 including a plurality of convex portions 47 is formed such that the direction in which the convex portions 47 extend is inclined by φ with respect to the circumferential direction S. Such a convex portion 47 can also be easily obtained by using a saw blade sharpening.

  In addition to the joining of the liner material end portions by welding as shown in FIGS. 1 to 3, in order to weld the inclined surfaces 43, 44 of the both end portions 41, 42 at correct positions, the positions of the both end portions 41, 42 are mutually determined. Positioning means for determining can be provided. As one of the positioning means, as shown in FIG. 5, pin holes 49 and 50 are formed in both end portions 41 and 42 in a state where the inclined surfaces 43 and 44 are opened at the alignment positions, and straddle the pin holes 49 and 50. For example, the positioning pin 51 is inserted. By determining the positions of both end portions 41, 42 of the liner material 40 with the positioning pins 51, both inclined surfaces 43, 44 are welded at the correct positions during welding, and the error of the inner liner circumferential length during welding work is minimized. can do. When the inclined surfaces 43 and 44 are welded, the positioning pin 51 is also welded in the pin holes 49 and 50. As a result, the diameter of the produced inner liner matches the diameter of the inner wall of the side wall inner unit 2 so that it can be fitted in the side wall 2 exactly.

  As another positioning means, as shown in FIG. 6, a stepped portion formed on a part of the inclined surfaces 43 and 44 can be used. That is, the inclined surface 43 has a stepped surface 52 that faces in the circumferential direction without inclining the inner edge portion, and the inclined surface 44 also has a peripheral surface without inclining the inner edge portion according to the stepped surface 52. As the complementary step surfaces 53 facing in the direction, the step surfaces 52 and the step surfaces 53 are brought into contact with each other, whereby the positions of both end portions 41 and 42 can be determined. Thus, the both ends of the liner material 40 can be positioned with a simple structure, and a weld joint that is reliable for welding can be provided.

  The inner liner and the molding method thereof according to the present invention have been described by taking an inner liner used in a plasma etching apparatus as an example of a semiconductor manufacturing apparatus. However, the present invention is not limited to an etching apparatus, for example, a CVD apparatus. The present invention can also be applied.

The cross-sectional view which shows the example of mounting | wearing with the inner liner which is one Embodiment of this invention. An example of an outline drawing of an inner liner. The welded joint side view which shows an example of a prior art. The welded joint side view which shows an example of a prior art. The welding joint side view which is one Embodiment of this invention. The welding joint top view which is one Embodiment of this invention. The welding joint side view which is one Embodiment of this invention. The welding joint side view which is one Embodiment of this invention. The side view which shows an example of the conventional welded joint structure given to an inner liner. The side view which shows another example of the conventional welded joint structure given to an inner liner.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Side wall 2 ... Side wall inner unit 3 ... Inner liner 4 ... Housing 5 ... Antenna 6 ... Ring 7 ... Dielectric plate 8 ... Antenna power supply 9 ... Bias power supply 10 ... Lower electrode 11 ... Gas supply means 12 ... Plate 13, 13A , 13B ... welded joint 15 ... treatment chamber 21, 22 ... both ends 23, 24 ... mating surface 25, 26 ... right angle surface 27, 28 ... notch 29, 30 ... mating surface 31 ... projection 40 ... liner material 41, 42 ... Both end portions 43, 44 ... inclined surface 45 ... convex portion 46 ... inner liner 47 ... convex portion 48 ... saw blade 49, 50 ... pin hole 51 ... positioning pin 52, 53 ... stepped surface We ... wafer D ... diameter T ... all plates Thickness W ... Axial width Bw ... Welding width θ ... Angle

Claims (8)

  In a cylindrical inner liner for a semiconductor manufacturing apparatus disposed in the processing chamber for the purpose of protecting the exposed part of the wall of the processing chamber of the semiconductor manufacturing apparatus from plasma, with respect to the radial direction of the belt-shaped liner material curved in a cylindrical shape A plurality of convex portions left apart in the axial width direction of the cylindrical shape by subjecting at least one of the inclined surfaces to the depth direction by processing both end portions formed with complementary inclined surfaces inclined An inner liner for a semiconductor manufacturing apparatus, which comprises welding at both inclined surfaces as a welding start region.   2. The inner liner for a semiconductor manufacturing apparatus according to claim 1, wherein the convex portion is a regular saw blade-shaped convex portion formed in a saw-tooth shape. 2. The inner liner for a semiconductor manufacturing apparatus according to claim 1 , wherein the both end portions are provided with positioning means for deciding each other position in order to weld the inclined surface at a correct position . The inner liner for a semiconductor manufacturing apparatus according to claim 1, wherein the liner material is a resin material such as polyimide, polyetherimide, or polybenzimidazole . In a molding method in which an inner liner that protects a wall exposed portion of a processing chamber of a semiconductor manufacturing apparatus from plasma is formed into a cylindrical shape, complementary slopes that are radially inclined at both ends of a belt-like liner material that is curved into a cylindrical shape Forming a plurality of protrusions left apart in the axial width direction of the cylindrical shape by forming a surface and processing at least one of the inclined surfaces in the depth direction, and forming the protrusions in a welding start region A method for forming an inner liner for a semiconductor manufacturing apparatus, comprising welding both the inclined surfaces. 6. The method of forming an inner liner for a semiconductor manufacturing apparatus according to claim 5 , wherein the convex portion is a regular saw-tooth convex portion formed in a saw-tooth shape . 6. The method of forming an inner liner for a semiconductor manufacturing apparatus according to claim 5 , wherein the inclined surfaces are welded at correct positions by positioning the positions of the both end portions with positioning means . 6. The method for molding an inner liner for a semiconductor manufacturing apparatus according to claim 5, wherein the liner material is a resin material such as polyimide, polyetherimide, polybenzimidazole or the like .

Images