JP2007103244A - Vacuum processing apparatus and high frequency power supplying method in vacuum processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vacuum processing apparatus provided with a transmission line for transmitting high frequency power of large power which is stably phase controlled for an electrode installed in a vacuum chamber, especially to carry out a film manufacturing process for a large area substrate using plasma, and to provide a high frequency power supplying method in the vacuum processing apparatus. <P>SOLUTION: The vacuum processing apparatus includes a microstrip line which can especially transmit the large power as a power supply line inside the vacuum chamber. In addition, the microstrip line has its ground provided as an inner wall of the vacuum chamber. Furthermore, the microstrip line includes; an impedance matching part which matches impedance between the high frequency power source and the electrode; and a reactance matching part for matching the impedance which is connected in parallel to the impedance matching part or connected serially between the impedance matching part and an electrode input end. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vacuum processing apparatus, and more particularly to a vacuum processing apparatus that performs processing on a substrate or a film-formed substrate using plasma, and a high-frequency power supply method in the vacuum processing apparatus.

  2. Description of the Related Art In recent years, in the field of manufacturing technology for thin film solar cell panels, in order to increase the productivity of thin film solar cell panels in response to increasing demand, the substrate area of thin film solar cell panels has been increased. For this reason, there is a need for a vacuum processing apparatus capable of forming a high-quality film on a large-area substrate in a short time.

  A schematic configuration of a conventional vacuum processing apparatus is shown in FIG. A conventional vacuum processing apparatus is installed on a ground in a vacuum chamber 10 for generating plasma, for example, an electrode 5 disposed facing a large glass substrate 6 for a solar cell panel, and an electrode 5 On the other hand, the deposition plate is installed in the opposite direction to the large glass substrate 6 and prevents the product from the plasma generated by the electrodes from adhering to the components other than the substrate installed in the vacuum chamber 10. 11. A coaxial cable 8 and a coaxial cable 9 for transmitting high-frequency power are connected to the electrode 5 installed in the vacuum chamber 10 via gas headers 4A and 4B which are upper and lower ends of the electrode 5, respectively. . Further, on each transmission line connecting the high frequency power supplies 1A, 1B for supplying high frequency power and the electrode 5, a matching box (matching box) 2A for controlling the voltage phase of the high frequency power at the electrode 5; 2B and power distributors 3A and 3B for distributing power to the plurality of electrodes 5 are respectively arranged in series. Gas is supplied into the vacuum chamber 10 and is converted into plasma by the high-frequency power supplied to the electrode 5. The film component molecules of the gas decomposed by the plasma are attracted to the ground side in the vacuum chamber 10 to form a thin film on the substrate 7.

  In order to form a film on the substrate with a large area of the thin-film solar cell panel using the above-described conventional vacuum processing apparatus, it is necessary to supply high-frequency high-frequency power to the electrode 5. . However, in order to supply a large high-frequency power to the electrode in the current vacuum processing apparatus, there are problems as described below.

(1) The coaxial cables 8 and 9 in the vacuum chamber 10 use ceramic beads or the like because an organic substance cannot be used as a dielectric. For this reason, the dielectrics in the coaxial cables 8 and 9 are discontinuous, and the voltage is applied to the high-frequency power input to both ends of the electrode 5 depending on the arrangement of the coaxial cables 8 and 9 in the vacuum chamber 10. A phase difference occurs.

(2) When transmitting large high-frequency power to the coaxial cables 8 and 9, since the heat dissipation of the coaxial cable is poor, heat distribution due to standing waves occurs in the coaxial cable during transmission of large power. And there is a fear of burning out in a portion where heat generation is large.

(3) Since it is difficult to manufacture a coaxial cable having an arbitrary characteristic impedance that can handle a large amount of power (on the side lower than 50Ω), it is difficult to configure a feed line that matches the impedance of the electrode 5 (generally lower than 50Ω).

  For this reason, in order to manufacture a thin-film solar cell panel having a large area and improve the production efficiency, the plasma is generated by efficiently injecting large power into the electrode 5 to form a film on the large-area substrate 6. The problem is how to improve the speed and how to accurately control the voltage phase of the high-frequency power at the electrode 5, and transmit the high-frequency power stably controlled by the voltage phase to the electrode 5. The establishment of a track is desired.

  In relation to the above technology, the following reports have been made.

  The "microwave plasma processing apparatus" disclosed in Japanese Patent Laid-Open No. 6-333697 includes a planar antenna that radiates microwaves to plasma and an electromagnet or permanent magnet that generates a magnetic field, and accelerates electrons with microwaves. In a plasma processing apparatus that generates plasma by impact ionization of neutral gas, a plane is formed by a material that can transmit microwaves to the boundary between the planar antenna and the plasma generation region and that is less affected by impurities in the processing process. The dielectric plate is separated from the planar antenna, and a metal plate is provided on the microwave feeding side of the planar antenna at a distance equal to or less than half the vacuum wavelength of the microwave, and the dielectric plate is disposed on the opposite side of the planar antenna of the metal plate. A microwave is distributed to each part of the planar antenna by a stripline circuit on the body or at a certain distance from the metal plate. Conductive microwave plasma processing apparatus has been proposed.

JP-A-6-333697

  The object of the present invention is to transmit high-capacity high-frequency power that is stably voltage phase-controlled to electrodes installed in a vacuum chamber in order to perform film formation on a large-area substrate using plasma in particular. It is providing the vacuum processing apparatus provided with the transmission line to perform, and the high frequency electric power supply method in a vacuum processing apparatus.

  In the following, means for solving the problem will be described using reference numerals with parentheses used in [Best Mode for Carrying Out the Invention]. These symbols are added in order to clarify the correspondence between the description of [Claims] and the description of the best mode for carrying out the invention. ] Should not be used for interpretation of the technical scope of the invention described in the above.

  The vacuum processing apparatus (50) of the present invention is disposed so as to face a vacuum chamber (62) and a substrate (63) placed on a common ground (51) set inside the vacuum chamber. An electrode (54), a deposition plate (64) disposed in a direction opposite to the substrate with respect to the electrode and electrically connected to a common ground, both ends of the electrode, and both ends of the electrode Corresponding to each part, introduction terminals (57a, 57b) provided on the wall part (51) of the vacuum chamber for introducing high-frequency power output from a high-frequency power source arranged outside to the inside of the vacuum chamber; And a microstrip line (52A, 52B) for transmitting high-frequency power output from the high-frequency power source (58A, 58b) to both ends of the electrodes, respectively. It is arranged so that the ground line is coincident with the common ground, also, the microstrip line length, radio frequency power to both ends of the respective electrodes are set to be input at the same voltage phase.

  Further, the microstrip lines (52A, 52B) in the vacuum processing apparatus (50) of the present invention function as an impedance matching unit for matching the impedance between the introduction terminals (57a, 57b) and the electrode (54). To have.

  Moreover, in the vacuum processing apparatus (50) of this invention, an impedance matching part (52A, 52B) is comprised by the conductor pattern (52a4) which has several line width.

  Further, the vacuum processing apparatus (50) of the present invention is further connected in parallel to the impedance matching portions (52a2, 52b2), (52a3, 52b3), or the impedance matching portion and the end of the electrode (54). Are provided with a reactance matching section (52a4, 52b4) for impedance matching connected in series.

  Moreover, the conductor part (52a) of the microstrip line in the vacuum processing apparatus (50) of the present invention is filled with the dielectric (52c) on the entire circumference.

  Moreover, in the vacuum processing apparatus (50) of this invention, the current frequency of the high frequency electric power output from the high frequency power supply (58A, 58B) arrange | positioned outside covers the frequency band from 10 MHz to 200 MHz.

  Moreover, the high frequency electric power supply method in the vacuum processing apparatus (50) of this invention is for introducing the high frequency electric power output from the high frequency electric power source (58A, 58B) arrange | positioned outside into the inside of a vacuum chamber (62). A high-frequency power supply step for supplying lead terminals (57a, 57b) provided on the wall (51) of the vacuum chamber, and respective ends of the electrodes (54) installed in the vacuum chamber for generating plasma; By adjusting the length of each of the microstrip lines (52A, 52B) connecting to the introduction terminal, a high-frequency power voltage phase matching step for inputting high-frequency power at the same voltage phase to each end of the electrode is provided. .

  In addition, the high frequency power supply method in the vacuum processing apparatus of the present invention further adjusts the setting of the characteristic impedance of each of the microstrip lines (52A, 52B) after the voltage phase matching step of the high frequency power to introduce the introduction terminal (57a , 57b) and the electrode (54), an impedance matching step for performing impedance matching is provided.

  The high-frequency power supply method in the vacuum processing apparatus (50) of the present invention is further connected in parallel to the impedance matching units (52a2, 52b2) and (52a3, 52b3) after the impedance matching step, or A reactance matching step of adjusting reactance matching units (52a4, 52b4) connected in series between the impedance matching unit and the end of the electrode to perform reactance matching is provided.

  According to the present invention, in particular, a power supply for supplying a large-capacity high-frequency power that is stably voltage phase-controlled to an electrode installed in a vacuum chamber in order to perform a film formation process on a large-area substrate using plasma. A vacuum processing apparatus including a line and a high-frequency power supply method in the vacuum processing apparatus can be provided.

  Thereby, the film-forming speed | rate on a large area board | substrate can be improved by injecting large electric power by which the voltage phase control was carried out to an electrode efficiently, and generating a plasma. In film formation, the voltage phase of the high-frequency power at the electrode is effectively varied to achieve a uniform plasma density on the substrate and a uniform film thickness formed on the substrate. . And the production efficiency of a large-area thin-film solar cell panel can be improved while maintaining the quality. In addition, the improvement of the reliability of the power supply line at the time of high power transmission makes it possible to reduce the material cost and the work cost required for the maintenance of the power supply line, thereby improving the reliability of the entire vacuum apparatus.

  With reference to the attached drawings, a best mode for carrying out a high-frequency power supply method in a vacuum processing apparatus and a vacuum processing apparatus according to the present invention will be described below.

  The vacuum processing apparatus of the present invention includes a microstrip line capable of transmitting particularly large electric power as a feed line inside the vacuum chamber. Then, by setting the lengths of the microstrip lines that supply power to the upper and lower ends of the electrodes optimally, it is possible to input high-frequency power having a uniform voltage phase to the upper and lower ends of the electrodes. For this reason, the voltage phase at the time of high frequency power input to the electrode is stabilized, and irregular voltage phase fluctuations hardly occur in the electrode during operation of the apparatus. Further, the microstrip line according to the embodiment of the present invention uses the ground as the inner wall of the vacuum chamber. For this reason, the cooling capability of the feed line inside the vacuum chamber is high, and accidents such as damage or melting of the line due to temperature rise of the feed line can be prevented in advance.

Thereby, the reliability improvement of the vacuum processing apparatus at the time of high power film formation is realized.

  The microstrip line provided in the vacuum processing apparatus according to the embodiment of the present invention is connected in parallel to the impedance matching unit for matching impedance between the high-frequency power source and the electrode, and the impedance matching unit. Or a reactance matching unit for impedance matching connected in series between the impedance matching unit and the electrode input terminal. And in the vacuum processing apparatus of this invention, when it sees from the said high frequency power supply side, perfect matching can be taken with respect to an electrode, and a power loss can be suppressed to the level of 0.1%. Thus, in the embodiment of the present invention, a high-efficiency vacuum processing apparatus for performing film forming processing using a large amount of power for a large-area substrate, and a high-frequency power supply method in the vacuum processing apparatus are provided. be able to.

  The structure of the feed line described above is a technique that can be applied to a low frequency device (13.56 MHz conventionally used) in principle, but the length of the feed line is output from a high frequency power source. Since it is based on ¼ of the electromagnetic wave wavelength at the frequency of the electric power, it is larger than the size of the vacuum chamber or the size of the substrate to be formed, and has not been used so far. More specifically, when the frequency is 13.56 MHz, the wavelength is (3 × 10E8) / (13.56 × 10E6) = 22.1 m, and ¼ of the wavelength is 5.5 m. Since this value is larger than the size of a conventional vacuum apparatus, it is difficult to configure a feed line in the vacuum chamber.

  However, in the vacuum processing apparatus according to the present invention, the wavelength is shortened by the fact that the chamber size has become about 2 m due to the increase in the size of the substrate to be deposited, and the deposition frequency has increased. Since the length of the / 4 wavelength is smaller than the size of the chamber, it is easy to provide a transmission line using a planar circuit in the chamber. Specifically, when the frequency is 60 MHz, the wavelength is (3 × 10E8) / (60 × 10E6) = 5.0 m, and ¼ of the wavelength is 1.25 m.

This value is almost the same as the size of the vacuum apparatus according to the embodiment of the present application, and it has become practical to apply a feed line constituted by a microstrip line in the vacuum chamber. In the actual production of the feed line, a dielectric having a large relative dielectric constant is used for the substrate of the microstrip line, so the length of the line corresponding to a quarter wavelength (mechanical length) is 1.25 m. Is even shorter.

(Embodiment 1)
FIG. 2 shows a schematic configuration of the vacuum processing apparatus according to Embodiment 1 of the present invention. The vacuum processing apparatus 50 according to the present embodiment is installed on a ground in a vacuum chamber 62 for generating plasma gas, for example, facing a large glass substrate 63 for a solar panel, A plasma electrode 54 disposed on the inner wall via a supporting insulating insulator 53 and components other than the substrate 63 installed in the opposite direction to the large glass substrate 63 with respect to the plasma electrode 54 and installed in the vacuum chamber 62 And an adhesion preventing plate 64 for preventing the product from the plasma generated by the plasma electrode 54 from adhering. Further, the plasma electrode 54 installed in the vacuum chamber 62 has power supply lines for transmitting high-frequency power output from the high-frequency power sources 58A and 58B installed outside the vacuum chamber, respectively. Connected through. In particular, the vacuum processing apparatus 50 according to the present embodiment includes microstrip lines 52A and 52B capable of transmitting a large amount of power as feed lines inside the vacuum chamber 62.

  A schematic configuration of a microstrip line provided in the present embodiment is shown in FIGS. 3A and 3B. The microstrip line provided in the present embodiment has been developed for the purpose of suppressing high-frequency power voltage phase fluctuation and transmitting large power. As shown in FIG. 3A (a), the microstrip line provided in the present embodiment has a vacuum chamber 51 wall as a ground as a ground, and a dielectric 52b and a conductor 52a are sequentially stacked thereon. It is. As shown in FIG. 3A (b), the schematic configuration in which the microstrip line is arranged on the inner wall of the vacuum chamber 51 is such that the dielectric 52b itself is in the hole 70 provided on the inner wall of the vacuum chamber 51. It is fixed by a fixing bolt 74 via an ellipse 71 provided in the. Then, the conductor 52a is fixed to the hole 72 provided on the dielectric 52b by an insulating bolt 75 through an ellipse 73 provided on the dielectric 52b, and finally, as shown in FIG. 3A (c). A cross-sectional form is constructed. In the present embodiment, the cross-sectional shape shown in FIG. 3B is not limited to the cross-sectional shape shown in FIG. 3A (c). In the cross-sectional form shown in FIG. 3B, a cover material 52c, which is the same material as the dielectric 52b, is further laminated on the dielectric 52b and the conductor 52a. In the microstrip line having the cross-sectional shape shown in FIG. 3B, a short circuit of power occurs due to breakage of the conductor 52a during plasma deposition or adhesion of a conductive substance between the wall surface of the vacuum chamber 51 and the conductor 52a. It is prevented.

  A plurality of high-frequency power sources 58B arranged outside the vacuum chamber 62 and supplying power to the upper end portion of the plasma electrode 54 are arranged outside the vacuum chamber 62 and a matching circuit 59B for impedance matching and inside the vacuum chamber. The electrical connection between the outside and the inside of the vacuum chamber is provided on the wall surface of the vacuum chamber 62 via a distributor 61B that distributes power to the plasma electrode (one of which is shown). Is electrically connected to the introduction terminal 57b. The introduction terminal 57b is connected to the microstrip line 52B via a conductor plate 56b such as copper or stainless steel inside the vacuum chamber. The microstrip line 52B is placed on the inner wall surface of the vacuum chamber 51 so that the inner wall of the vacuum chamber 51 is grounded. The microstrip line 52B is further electrically connected to the upper end of the plasma electrode 54 via a conductor plate 55b made of copper or stainless steel. On the other hand, a high-frequency power source 58A that is disposed outside the vacuum chamber 62 and supplies power to the lower end of the plasma electrode 54 includes a matching circuit 59A for impedance matching outside the vacuum chamber 62, and a plurality of components inside the vacuum chamber. It is installed on the wall surface of the vacuum chamber 62 via a distributor 61A that distributes power to the plasma electrodes (one of which is shown in the figure) and is electrically connected to the outside and inside of the vacuum chamber. It is electrically connected to the lead-in terminal 57a that takes a good conduction. The introduction terminal 57a is connected to the microstrip line 52A through a conductor plate 56a such as copper or stainless steel inside the vacuum chamber 62. The microstrip line 52A is placed on the inner wall surface of the vacuum chamber 51 so that the inner wall of the vacuum chamber 51 is grounded. The microstrip line 52A is further electrically connected to the lower end of the plasma electrode 54 through a conductor plate 55a such as copper or stainless steel.

  In the present embodiment, the lengths of the microstrip line 52A and the microstrip line 52B are high frequency so that the voltage of the power supplied from the outside is input in the same phase at the upper end and the lower end of the plasma electrode 54. The current frequency of the power supplied from the power sources A and B is set to ½ of the wavelength in the transmission line. However, if the voltage of the power supplied from the outside is set to be input in the same phase at the upper end and the lower end of the plasma electrode 54, the length of the microstrip line 52A and the microstrip line 52B is set to the high frequency power source A. And B is not limited to ½ of the transmission line wavelength of the current frequency of the power supplied from B. Further, the length of the conductor plates 56a, 56b such as copper or stainless steel for connecting the introduction terminals 57a, 57b and the microstrip lines 52A, 52B, and the upper and lower ends of the microstrip lines 52A, 52B and the plasma electrode 54 The length of the conductive plates 55a, 55b made of copper, stainless steel or the like for connecting them is preferably 1/50 or less of the free space wavelength of the current frequency of the power supplied from the high frequency power supplies A and B, respectively. .

(Operation principle of Embodiment 1)
When the vacuum processing apparatus 50 according to this embodiment is activated, high-frequency power having the same specified frequency is output from the high-frequency power supplies 58A and 58B with the same voltage phase. The high-frequency power output at the same voltage phase is input to the distributors 60A and 60B via impedance matching circuits 59A and 59B for impedance matching between the high-frequency power sources 58A and 58B and the respective feed lines (50Ω). . The electric power output from the distributor 60B is introduced into the vacuum chamber 62 through the coaxial cable 61B and the introduction terminal 57b. Then, it passes through a conductor plate 56b such as copper or stainless steel that electrically connects the introduction terminal 57b and the microstrip line 52B, and is input to the microstrip line 52B having the inner wall surface of the vacuum chamber 51 of the vacuum chamber 62 as the ground. The high-frequency power is transmitted to the microstrip line 52B, and finally input to the plasma electrode 54 via a conductor plate 55b such as copper or stainless steel that electrically connects the upper end of the electrode and the microstrip line 52B. The On the other hand, the high frequency power output from the distributor 60A is introduced into the vacuum chamber 62 through the coaxial cable 61A via the introduction terminal 57a. Then, it passes through a conductor plate 56a such as copper or stainless steel that electrically connects the introduction terminal 57b and the microstrip line 52B, and is input to the microstrip line 52A having the vacuum chamber 51 inner wall surface of the vacuum chamber 62 as the ground. The high-frequency power is transmitted to the microstrip line 52A, and is finally input to the plasma electrode 54 via a conductor plate 55a such as copper or stainless steel that electrically connects the lower end of the electrode and the microstrip line 52A. The

One specific pattern shape of the microstrip line provided in the vacuum processing apparatus 50 according to the present embodiment is shown in FIG. 4A. In the present embodiment, the line lengths of the microstrip line 52A and the microstrip line 52B (the conductor 52b1 and the alumina substrate 52a1) are set to 1 of the free space wavelength of the current frequency in the power output from the high frequency power supplies 58A and 58B, respectively. Since the length is set to / 2, power having the same phase is input to the upper and lower ends of the plasma electrode 54 at the voltage of the high frequency power. Further, the characteristic impedance between the microstrip line 52A and the microstrip line 52B in the present embodiment is that impedance matching between the power supply line for transmitting high frequency power from the high frequency power sources 58A and 58B to the plasma electrode 54 and the plasma electrode 54 is performed. Is 50Ω so as to match with general 50Ω (refer to the electrical characteristic list in FIG. 5). FIG. 6A shows impedance plotted based on the pattern shape of the microstrip line according to the present embodiment on the Smith chart (position indicated by “0”). According to this result, the voltage standing wave ratio (VSWR) according to the high frequency power feeding method by the vacuum processing apparatus 50 in the present embodiment is 2.76 (the power loss of the power to be supplied to the plasma electrode 54 is 22%). I know that there is.

  As described above, in the vacuum processing apparatus 50 according to the present embodiment, (a) as a feed line inside the vacuum chamber 51, by providing a microstrip line capable of transmitting particularly large power, High-frequency power with the same voltage phase can be input to the upper and lower ends of the device, and the voltage phase difference during power transmission is stable. Is unlikely to occur. For this reason, the voltage phase control of the plasma generated by the electrodes is facilitated, and the quality of the thin film formed on the substrate 63 to be deposited is improved. In addition, since a large amount of power can be stably supplied to the plasma electrode 54, the deposition rate can be dramatically increased even when the area of the substrate 63 to be deposited is increased.

(B) In addition, since the microstrip line according to the present embodiment uses the ground as the inner wall of the vacuum chamber 51, the cooling capacity of the feed line inside the vacuum chamber 51 is high, and the line is damaged due to the temperature rise of the feed line. And accidents such as melting can be prevented in advance. As a result, the reliability of the apparatus during high-power film formation is improved.

(C) In the present embodiment, a microstrip line having the inner wall of the vacuum chamber 51 as a ground is provided as a feed line inside the vacuum chamber 51, and the microstrip line is electrically connected via a copper plate. Connected to the electrode mechanically and mechanically. For this reason, even when the vacuum processing device is in operation, the electrical connection between the coaxial cable and the electrode is fixed only with the core wire of the coaxial cable, and the electrical and mechanical connection between the feed line and the electrode Reliability is improved. This also makes it possible to reduce the maintenance time and maintenance cost for the entire apparatus, thereby improving the reliability. Furthermore, by improving the plasma controllability of the electrode in the vacuum processing apparatus 50 according to the present embodiment, the film thickness distribution formed on the substrate can be improved, and the quality of the solar cell and the power generation performance can be improved. In addition, the number of production steps and the production time by the vacuum processing apparatus can be shortened.

(Embodiment 2)
The basic configuration of the vacuum processing apparatus according to the second embodiment of the present invention and the high-frequency power supply method in the vacuum processing apparatus are the same as those in the first embodiment. However, the microstrip line pattern provided in the vacuum processing apparatus 50 according to the present embodiment is different from the microstrip line in the first embodiment in that the introduction terminals 57 a and 57 b provided on the wall surface of the vacuum chamber 51 and the plasma electrode 54 are provided. It becomes an impedance matching part for matching the impedance between.

One specific pattern shape of the impedance matching section provided in the vacuum processing apparatus 50 according to the present embodiment is shown in FIG. 4B. In the present embodiment, since the microstrip line 52A and the microstrip line 52B function as the impedance matching portions (conductor 52b2 and alumina substrate 52a2), the upper and lower end portions of the plasma electrode 54 are provided. The high-frequency power having the same phase in voltage is input with extremely low loss.

In particular, in the present embodiment, the transmission line electrical length of the impedance matching unit is set to ¼ of the wavelength in free space corresponding to the current frequency of the high-frequency power output from each of the high-frequency power supplies 58A and 58B. The characteristic impedance of the transmission line is set to an intermediate value between the impedance at the introduction terminals 57 a and 57 b and the impedance of the plasma electrode 54. That is, the characteristic impedance Zm of the impedance matching section having the ¼ wavelength is Zm = (Z1 × Z0) ^{1/2 where} Z1 is the impedance of the plasma electrode 54 and Z0 is the impedance of the introduction terminals 57a and 57b. (Refer to the list of electrical characteristics in FIG. 5). When the apparatus is actually in operation, the impedance of the plasma electrode 54 is lower than 50Ω, and in the microstrip line pattern design in the present embodiment, the plasma electrode 54 described above is substantially in impedance. By adopting a simple impedance as the value of Z1, an optimal microstrip line can be realized as appropriate.

  FIG. 6B shows a plot of impedance on the Smith chart (position indicated by “1”) based on the pattern shape of the microstrip line according to the present embodiment. According to this result, the voltage standing wave ratio (VSWR) by the high frequency power feeding method by the vacuum processing apparatus 50 in this embodiment is 2.0 (the power loss of the power to be supplied to the plasma electrode 54 is 11.1%). ).

As described above, in the vacuum processing apparatus 50 according to the present embodiment, in addition to the functions and effects described in the first embodiment,
(D) In the microstrip line serving as the impedance matching portion (conductor 52b2 and alumina substrate 52a2), the impedance viewed between the introduction terminals 57a and 57b and the plasma electrode 54 is performed, whereby the voltage viewed from the high frequency power sources 58A and 58B. The standing wave ratio (VSWR) can be reduced. Thereby, it is possible to realize a highly reliable vacuum processing apparatus capable of suppressing Joule heat generation due to standing waves on the feed line.

(E) In addition, since the reduction of power loss can be realized, the capacity of the actually used high-frequency power supplies 58A and 58B can be reduced, and the economic efficiency of the entire vacuum processing system having this embodiment can be improved. To do.

(Embodiment 3)
The basic configuration of the vacuum processing apparatus according to the third embodiment of the present invention and the high-frequency power supply method in the vacuum processing apparatus are the same as those in the second embodiment. However, the microstrip line pattern provided in the vacuum processing apparatus 50 according to the present embodiment is further connected in parallel to the impedance matching unit provided in the second embodiment, or the impedance matching unit and the impedance matching unit. A reactance matching unit is provided which is connected in series between the upper end or the lower end of the plasma electrode 54 so that the impedance viewed from the output end of the impedance matching unit becomes a pure resistance component.

  FIG. 4C shows one specific pattern shape of the microstrip lines (52a3, 52b3) configured by the impedance matching unit and the reactance matching unit provided in the vacuum processing apparatus 50 according to the present embodiment. In the present embodiment, the microstrip line 52A and the microstrip line 52B are viewed from the impedance matching between the introduction terminals 57a and 57b and the plasma electrode 54 and the output end of the impedance matching unit. In the case of the first and second embodiments, high-frequency power having the same phase in the voltage is applied to the upper and lower ends of the plasma electrode 54 because it has a function of performing reactance matching so that the impedance becomes a pure resistance component. It is input with even lower loss.

  In particular, in the present embodiment, the transmission line electrical length of the impedance matching unit is 1 in the free space wavelength corresponding to the current frequency of the high-frequency power output from each of the high-frequency power supplies 58A and 58B, as in the second embodiment. / 4, and at the same time, the characteristic impedance of the transmission line in this portion is set to an intermediate value between the impedance at the introduction terminals 57a and 57b and the impedance of the plasma electrode 54. In addition, the reactance matching unit is set, for example, such that the characteristic impedance is 50Ω, the transmission line electrical length is such that the impedance viewed from the output end of the impedance matching unit is a pure resistance component (FIG. 5). See electrical characteristics list).

  FIG. 6C shows impedance plotted based on the pattern shape of the microstrip line according to the present embodiment on the Smith chart (position indicated by “2”). According to this result, the impedance viewed from the output end portion of the impedance matching portion is substantially the same as the impedance of the plasma electrode 54, and the reactance component is also removed. The voltage standing wave ratio (VSWR) according to the high frequency power feeding method by the vacuum processing apparatus 50 in the present embodiment is 1.06 (the power loss of the power to be supplied to the plasma electrode 54 is 0.1%). I understand.

As described above, in the vacuum processing apparatus 50 according to the present embodiment, in addition to the operational effects described in the first or second embodiment,
(F) In addition to the impedance matching unit provided in the second embodiment, a reactance matching unit is further provided so that the impedance viewed from the output end of the impedance matching unit is a pure resistance component. The load of the plasma electrode 54 viewed from the power sources 58A and 58B side is a pure resistance. For this reason, when viewed from the high-frequency power supplies 58A and 58B, perfect matching can be achieved with respect to the plasma electrode 54, and power loss can be suppressed to a level of 0.1%.

  Therefore, in this embodiment, it is possible to provide a high-efficiency vacuum processing apparatus for performing a film forming process using a large amount of power on a large-area substrate, and a high-frequency power supply method in the vacuum processing apparatus. it can. In the description of the present embodiment, the case where the reactance matching unit is connected in series to the electrode side end of the impedance matching unit has been described. However, the reactance matching unit is connected in parallel to the impedance matching unit. It is good also as a form.

(Embodiment 4)
The basic configuration of the vacuum processing apparatus according to the fourth embodiment of the present invention and the high-frequency power supply method in the vacuum processing apparatus are the same as those in the third embodiment. However, in the microstrip line pattern provided in the vacuum processing apparatus 50 according to the present embodiment, the impedance matching section has a multi-stage structure in order to cope with a wider frequency band.

  FIG. 4D shows one specific pattern shape of the microstrip lines (52a4, 52b4) configured by the impedance matching unit and the reactance matching unit provided in the vacuum processing apparatus 50 according to the present embodiment. In the present embodiment, the microstrip line 52A and the microstrip line 52B have impedance matching corresponding to a wider frequency band between the introduction terminals 57a and 57b and the plasma electrode 54, and the impedance matching unit. Because of having a function of performing reactance matching so that the impedance viewed from the output end of the output becomes a pure resistance component, high-frequency power having the same phase in voltage is applied to the upper and lower ends of the plasma electrode 54. The input is performed with low loss corresponding to a wider power supply frequency than in the case of the third mode.

In particular, in the present embodiment, when the transmission line of the impedance matching unit has the impedance of the plasma electrode 54 as Z1 and the impedance of the introduction terminals 57a and 57b as Z0, the first and second quarter wavelengths. The characteristic impedances Zm1 and Zm2 of the transmission lines are set to have a relationship of Zm1 = (Z1 ³ × Z0) ^1/4 and Zm2 = (Z1 × Z0 ³ ) ^1/4 . (See the electrical property list in FIG. 5).

  FIG. 6D shows impedance plotted based on the pattern shape of the microstrip line according to the present embodiment on the Smith chart (position indicated by “3”). According to this result, the impedance viewed from the output end of the impedance matching unit is substantially the same as the impedance of the plasma electrode 54 as shown in the third embodiment, and the reactance component is also removed. Yes. The voltage standing wave ratio (VSWR) according to the high frequency power feeding method by the vacuum processing apparatus 50 in the present embodiment is 1.06 (the power loss of the power to be supplied to the plasma electrode 54 is 0.1%). I understand.

As described above, in the vacuum processing apparatus 50 according to the present embodiment, in addition to the effects described in the first to third embodiments,
(G) In plasma control of the plasma electrode 54, it is easy to apply a method by superimposing a plurality of frequencies or frequency modulation in addition to phase modulation. For this reason, when viewed from the high-frequency power sources 58A and 58B, complete matching with the plasma electrode 54 can be achieved over a wider frequency range than in the first to third embodiments.

  For this reason, in the present embodiment, a high-efficiency vacuum processing apparatus for performing a film forming process using a large amount of power on a large-area substrate, and a high-frequency power supply method excellent in reliability in the vacuum processing apparatus Can be provided.

It is a figure which shows schematic structure of the conventional vacuum processing apparatus. It is a figure which shows schematic structure of the vacuum processing apparatus concerning this Embodiment. It is a figure which shows schematic structure of the microstrip line with which the vacuum processing apparatus concerning this Embodiment is equipped. It is a figure which shows schematic structure of the microstrip line with which the vacuum processing apparatus concerning this Embodiment is equipped. 2 is a diagram showing a pattern shape of a microstrip line provided in the vacuum processing apparatus according to Embodiment 1. FIG. It is a figure which shows the pattern shape of the microstrip line with which the vacuum processing apparatus concerning Embodiment 2 is equipped. It is a figure which shows the pattern shape of the microstrip line with which the vacuum processing apparatus concerning Embodiment 3 is equipped. It is a figure which shows the pattern shape of the microstrip line with which the vacuum processing apparatus concerning Embodiment 4 is equipped. It is a figure which shows the electrical property list based on the pattern shape of the microstrip line with which the vacuum processing apparatus concerning Embodiment 1-3 is equipped. It is the figure which showed on the Smith chart the impedance based on the pattern shape of the microstrip line with which the vacuum processing apparatus concerning Embodiment 1 is equipped. It is the figure which showed on the Smith chart the impedance based on the pattern shape of the microstrip line with which the vacuum processing apparatus concerning Embodiment 2 is equipped. It is the figure which showed on the Smith chart the impedance based on the pattern shape of the microstrip line with which the vacuum processing apparatus concerning Embodiment 3 is equipped. It is the figure which showed on the Smith chart the impedance based on the pattern shape of the microstrip line with which the vacuum processing apparatus concerning Embodiment 4 is equipped.

Explanation of symbols

1A ... High frequency power supply A
1B ... High frequency power supply B
2A, 2B ... Matching box 3A, 3B ... Power distributor 4A, 4B ... Gas header 5 ... Ladder electrode 6 ... Substrate 7 ... Earth electrode 8 ... Coaxial cable (upper side)
9 ... Coaxial cable (lower side)
DESCRIPTION OF SYMBOLS 10 ... Vacuum chamber 11 ... Depositing plate 50 ... Vacuum processing apparatus 51 ... Vacuum chamber (wall)
52 ... Microstrip lines 52a, 52a1, 52a2, 52a3, 52a4 ... Conductors 52b, 52b1, 52b2, 52b3, 52b4 ... Dielectric 52c ... Cover material 53 ... Support insulation 54 ... Plasma electrodes 55a, 55b, 56a, 56b ... Conductors Plate 57 ... Introducing terminals 58A, 58B ... High frequency power supplies 59A, 59B ... Matching circuits 60A, 60B ... Distributors 61A, 61B ... Coaxial cable 62 ... Vacuum chamber 63 ... Substrate 64 ... Depositing plates 70, 72 ... Holes 71, 73 ... Long hole 74 ... Fixing bolt 75 ... Insulating bolt

Claims (9)

A vacuum chamber;
An electrode disposed to face a substrate placed on a common ground set inside the vacuum chamber;
An adhesion preventing plate disposed in a direction opposite to the substrate with respect to the electrode and electrically connected to the common ground;
The vacuum for introducing high-frequency power output from a high-frequency power source arranged outside corresponding to both ends of the electrode and both ends of the electrode into the vacuum chamber. A microstrip line for connecting to an introduction terminal provided on a wall of the chamber and transmitting the high-frequency power output from the high-frequency power source to each of the ends of both electrodes,
Each of the microstrip lines is disposed so that the ground of the microstrip line coincides with the common ground, and the length of the microstrip line is determined so that the high-frequency power is applied to both ends of the electrodes. A vacuum processing device that is set to be input at the same voltage phase. The vacuum processing apparatus according to claim 1,
The vacuum processing apparatus, wherein the microstrip line is an impedance matching unit for matching impedance between the introduction terminal and the electrode. The vacuum processing apparatus according to claim 2,
The impedance matching unit is a vacuum processing apparatus configured by a conductor pattern having a plurality of line widths. The vacuum processing apparatus according to claim 2 or 3,
Furthermore, a vacuum processing apparatus comprising a reactance matching unit for impedance matching connected in parallel to the impedance matching unit or connected in series between the impedance matching unit and the end of the electrode. The vacuum processing apparatus according to at least one of claims 1 to 4,
A vacuum processing apparatus in which the conductor of the microstrip line is filled with a dielectric around the entire circumference. The vacuum processing apparatus according to at least one of claims 1 to 5,
The vacuum processing apparatus in which the current frequency of the high-frequency power output from the high-frequency power source arranged outside includes a frequency band from 10 MHz to 200 MHz. A high-frequency power supply step for supplying high-frequency power output from a high-frequency power source arranged outside to an introduction terminal provided on the wall of the vacuum chamber for introducing the inside of the vacuum chamber;
By adjusting the length of each microstrip line that connects each end of the electrode for generating plasma that is installed in the vacuum chamber and the introduction terminal, to each end of the electrode A high-frequency power supply method in a vacuum processing apparatus, comprising: a high-frequency power voltage phase matching step for inputting the high-frequency power so as to have the same voltage phase. In the high frequency electric power supply method in the vacuum processing apparatus of Claim 7,
Further, after the voltage phase matching step of the high-frequency power, a vacuum processing including an impedance matching step of adjusting the setting of the characteristic impedance of each of the microstrip lines and performing impedance matching between the introduction terminal and the electrode A high-frequency power supply method in an apparatus. In the high frequency electric power supply method in the vacuum processing apparatus of Claim 7 or 8,
Further, after the impedance matching step, a reactance matching unit connected in parallel to the impedance matching unit or connected in series between the impedance matching unit and the end of the electrode is adjusted. A high-frequency power supply method in a vacuum processing apparatus including a reactance matching step for performing reactance matching.

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