TWI450644B - Plasma processing device - Google Patents

Description

Plasma processing device

The present invention relates to a plasma processing apparatus which generates a plasma in a vicinity of a substrate to be processed in a vacuum vessel, and then deposits or etches the substrate to be processed using the plasma.

The plasma processing apparatus is widely used for stacking processing, etching processing, cleaning processing, and the like. For example, a plasma is produced from a crucible and a gas containing nitrogen, and a tantalum nitride film is deposited on a glass substrate, thereby obtaining a substrate used for a liquid crystal display or a solar cell. Here, the tantalum nitride film has a function as a passivation film for preventing diffusion of impurities from the glass. Further, when a liquid crystal display or a solar cell is produced using such a substrate, the entire surface or a part thereof is subjected to an etching treatment or a cleaning treatment, and thereafter, the substrate to which the plasma treatment is applied (in the above-described example, a glass substrate) is referred to as The substrate is processed.

In recent years, the number of substrates to be processed has become large, or even if the size of the substrate to be processed is as conventional, the number of substrates to be processed is also increased, and the plasma processing apparatus is becoming larger. Among them, in the case of processing a large-sized substrate to be processed, in the case where a plurality of relatively small-sized substrates to be processed are processed as a whole, it is necessary to uniformly generate plasma for all of them. For example, the quality of the film thickness or the like of the film formed on the glass substrate must be within a limited range. Therefore, although the plasma generation region becomes large, it is required that the variation of the density of the plasma generated in the plasma processing apparatus is within a fixed range.

In the plasma processing apparatus, there are ECR (electron cyclotron resonance) plasma method, microwave plasma method, inductively coupled plasma method, and capacitive coupling plasma method. Wherein, the inductively coupled plasma processing device introduces gas into the interior of the vacuum vessel and causes the high-frequency current to flow to the high-frequency antenna (induction coil), thereby accelerating the electrons in the interior of the vacuum vessel by the induced induced electric field, so that The electrons collide with the gas molecules, thereby ionizing the gas molecules to produce a plasma. For example, Patent Document 1 describes an inductively coupled plasma processing apparatus in which one spiral coil is placed on the zenith on the outer side of the vacuum vessel. However, in the plasma processing apparatus described in Patent Document 1, the size of the plasma generation region is increased, and when the spiral coil is only enlarged, the difference in plasma density between the center portion and the peripheral portion is only Since it is simply enlarged, the criterion of the uniformity of the entire plasma generation region as described above cannot be satisfied. In addition, when the antenna is made large, the conductor of the antenna becomes long. Therefore, a standing wave is formed in the antenna, and the intensity distribution of the high-frequency current becomes uneven. As a result, the plasma density distribution may become uneven (see Patent Document 1).

Patent Document 2 and Non-Patent Document 1 describe a multi-antenna type inductively coupled plasma processing apparatus in which a plurality of high frequency antennas are attached to an inner wall of a vacuum container. According to the device, the distribution of the plasma in the vacuum vessel can be controlled by appropriately setting the configuration of the plurality of antennas. Moreover, since the length of the conductor of each antenna can be shortened, it is possible to prevent the adverse effect caused by the standing wave. For these reasons, the plasma processing apparatus described in Patent Document 2 and Non-Patent Document 1 can produce plasma having higher uniformity than ever.

[Patent Document 1] JP-A-2000-058297 ([0026] to [0027], FIG. 1)

[Patent Document 2] JP-A-2001-035697 ([0050], FIG. 11)

[Non-Patent Document 1] Kouhara Yuichi, "The Plasma Source for Large-Scale Processing of Next Generation Rice Sizes", Journal of Plasma and Fusion Research, Vol. 81, No. 2, pp. 85-93, issued in February 2005

According to the plasma processing apparatus described in Patent Document 2 and Non-Patent Document 1, the uniformity of the plasma density in the vacuum container is improved. However, in these devices, since about half of the generated plasma is not located on the center side of the vacuum container but diffuses toward the inner wall on which the antenna is mounted, it is not used for plasma treatment. Further, in the plasma CVD apparatus which forms a film to be processed, about half of the base atomic groups (membrane precursors) generated by the plasma adhere to the inner wall of the vacuum container to become particles, and the film is dropped to become a film. The reason for the quality reduction. Therefore, it is necessary to periodically perform cleaning in the vacuum container, and thus the operation rate of the apparatus is lowered. Moreover, since expensive cleaning gas is required to be used in a large amount, the running cost is increased.

The problem to be solved by the present invention is to provide a plasma processing apparatus which has high utilization efficiency of plasma and can suppress running costs.

A plasma processing apparatus of the present invention developed to solve the above problems is characterized by comprising:

a) a vacuum container;

b) a plasma generating means supporting portion arranged to protrude into the inner space of the vacuum container;

c) One or a plurality of plasma generating means are attached to the plasma generating means support portion.

The plasma generating means generates a plasma by ionizing gas molecules in the vacuum vessel. Various types of plasma generating means can be used, and as a representative example thereof, a high frequency antenna can be cited. Further, a slit or a high-frequency electrode or the like may be used as a plasma generating means.

In the present invention, the "plasma generating means supporting portion provided to protrude into the internal space of the vacuum container" also includes a vertical (horizontal) internal space.

In the plasma processing apparatus of the present invention, a plurality of the plasma generating means can be radially arranged from the plasma generating means supporting portion to the wall surface of the vacuum container. For example, the plasma generating means uses a high-frequency antenna, which can be on the side of the cylindrical plasma generating means support portion or the surface of the spherical plasma generating means supporting portion, from those facing the wall surface of the vacuum vessel (the outer side of the cylinder or the ball) Set a plurality of high frequency antennas.

The plasma processing apparatus of the present invention may include a base holding portion that holds a plurality of substrates to be processed to surround the plasma generating means supporting portion.

The base holding portion includes a revolution portion that rotates the substrate to be processed around the plasma generation means support portion, and/or a rotation portion that rotates the substrate to be processed.

Further, the base holding portion may include a film-like base holding portion that holds the film-like substrate such that the film-form substrate surrounds the plasma generating means supporting portion. In this case, the delivery unit may be configured to sequentially feed the strip-shaped film-like substrate to the film-form substrate holding portion, and the take-in portion to sequentially take the film from the film-form substrate holding portion. Matrix.

In the plasma processing apparatus of the present invention, the plasma generating means is attached to the plasma generating means supporting portion which is provided to protrude into the internal space of the vacuum container. Since the surface area of the plasma generating means supporting portion is generally smaller than the surface of the inner wall of the vacuum container, it is compared with the case where it is attached to the inner wall of the vacuum container as in the plasma processing apparatus described in Patent Document 2 and Non-Patent Document 1. The total area of the part where the plasma generating means is installed is smaller. Therefore, the utilization efficiency of the plasma is improved, and the deposit of the inner wall adhering to the vacuum vessel can be reduced in the plasma CVD apparatus. As a result, the frequency of cleaning the inner wall can be reduced, the operation rate of the apparatus can be improved, and the running cost can be suppressed.

In the case where the plasma processing apparatus of the present invention has a revolving portion, by rotating the periphery of the substrate to be processed around the plasma generating means support portion in the plasma processing, all of the substrates to be processed can be electrically operated under the same conditions. Slurry treatment.

In the case where the plasma processing apparatus of the present invention has a self-rotating portion, the surface of each substrate to be processed can be subjected to plasma treatment in the same manner by rotating the substrate to be processed.

By providing the film-form substrate holding portion in the plasma processing apparatus of the present invention, the surface of the film-form substrate can be appropriately subjected to plasma treatment. In particular, the film-form substrate is sequentially sent to and taken out from the region where the plasma is generated by the delivery portion and the take-in portion, whereby the plasma treatment can be performed over a large area.

An embodiment of the plasma processing apparatus of the present invention will be described using Figs. 1 to 4 .

[First Embodiment]

The plasma processing apparatus 10 of the first embodiment is a device for performing plasma treatment on the surface of a rod-shaped substrate to be processed 21. The plasma processing apparatus 10 of the present embodiment has a vacuum container 11 as in the related art, and as shown in Fig. 1, a liquid container 11 is provided so as to protrude from the vicinity of the center of the upper wall surface of the vacuum container 11 into the internal space 111 of the vacuum container 11. A cylindrical antenna (plasma generating means) support portion 12. On the outer peripheral surface of the antenna support portion 12, four rows are provided at equal intervals in the longitudinal direction of the column, and fourteen high-frequency antennas 13 of four are provided at equal intervals along the circumference. Each of the high-frequency antennas 13 bends a linear conductor into a U shape. Each of the high frequency antenna 13 and the power source 14 are connected in parallel, and one impedance integrator 15 is provided between all of the high frequency antenna 13 and the power source 14. The inside of the antenna supporting portion 12 is hollow, and wiring for connecting the above-described high frequency antenna 13 and the power source 14 is provided in the cavity. The cavity of the antenna supporting portion 12 may be connected to the vacuum vessel 11 or vice versa.

The base holding portion 16 is provided at the bottom of the vacuum vessel 11. The base holding portion 16 has a disk-shaped revolving portion 161 which is placed on a column 163 which is erected on the bottom surface of the vacuum container 11 and rotates around the column 163. The six rotation portions 162 are equally spaced (second The figure is disposed around the upper surface of the revolution portion 161 and is constituted by a circular plate rotatable around the center.

Further, in the present plasma processing apparatus 10, a vacuum pump for exhausting the internal space 111 or a gas introduction port for introducing the plasma material gas or the like is provided.

The operation of the plasma processing apparatus 10 of the present embodiment will be described. First, the rod-shaped substrate to be processed 21 is fixed in an upright state on the rotation portion 162. Next, after the internal space 111 is exhausted by a vacuum pump, a plasma raw material gas is introduced from the gas introduction port. Then, while the revolution portion 161 and the rotation portion 162 are rotated, high-frequency electric power is introduced from the power source 14 to the radio-frequency antenna 13, and a high-frequency electromagnetic field is generated in the vacuum container 11. The high-frequency electromagnetic field is used to ionize the molecules of the plasma material gas to become a plasma state, and the surface of the substrate to be processed 21 is subjected to plasma treatment such as etching treatment or deposition treatment.

In the plasma processing apparatus 10 of the present embodiment, since the area of the antenna portion to be mounted can be made smaller by using the antenna supporting portion 12 which is provided to protrude into the internal space 111 of the vacuum container 11, the high frequency antenna 13 is attached to the vacuum. In comparison with the case of the wall surface of the container 11, the loss of the plasma toward the mounting surface side can be more suppressed.

Further, in the plasma processing apparatus 10 of the present embodiment, since the substrate to be processed 21 is revolved around the antenna support portion 12 by the revolution portion 161, it is possible to perform plasma treatment on all of the substrates to be processed 21 under the same conditions. Further, in the plasma processing apparatus 10 of the present embodiment, since the substrate to be processed 21 is rotated by the rotation portion 162, the surface of each of the substrates to be processed 21 can be subjected to plasma treatment in the same manner.

A conventional plasma processing apparatus described in Patent Document 2 and Non-Patent Document 1. A plurality of high frequency antennas are dispersedly disposed on the wall surface of the vacuum vessel. Therefore, when a plurality of high-frequency antennas are connected to a small number of high-frequency power sources or impedance integrators, wiring becomes long, and power loss during power supply becomes large, and in order to suppress this power loss, a plurality of high-frequency power sources or When the impedance integrator is used, there is a problem of an increase in cost. In the plasma processing apparatus of the present embodiment, since the radio-frequency antenna 13 is collectively disposed in the antenna support unit 12, the wiring can be made shorter than in the related art, and both power loss and cost can be suppressed.

Further, in the present embodiment, although the antenna supporting portion 12 is a cylindrical member, other shapes such as a quadrangular prism may be used. The number of the antenna support units 12 may be one as shown in the embodiment, or may be plural. In order to reduce the area of the portion where the high-frequency antenna 13 is mounted and the loss when the power is supplied to the high-frequency antenna 13, the number of the antenna supporting portions 12 can be reduced (preferably only one), and the number of the antenna supporting portions 12 can be reduced. The high frequency antenna 13 is configured. Moreover, the position of the antenna support part 12 can also be changed suitably. The number of the high frequency antennas 13 can be appropriately changed according to the magnitude or uniformity of the required plasma density. These matters are the same for the other embodiments described below.

[Second Embodiment]

The plasma processing apparatus 30 of the second embodiment will be described using a top view shown in Fig. 3. The plasma processing apparatus 30 of the present embodiment is a device for performing an operation of moving the flat substrate-processed substrate 22 into the internal space 311 of the vacuum container 31 and carrying out the plasma processing from the vacuum container 31.

The plasma processing apparatus 30 of the present embodiment has an octagonal cylindrical vacuum vessel 31, and a hexagonal column-shaped antenna is provided so as to protrude from the vicinity of the center of the upper wall surface into the inner space 311 of the vacuum vessel 31 (plasma generation) Means) Support section 32. A plurality of high frequency antennas (plasma generating means) 33 are provided on each side surface of the hexagonal column of the antenna supporting portion 32 so as to be arranged in a line in the vertical direction. Each of the high-frequency antennas 33 is a U-shaped antenna, and is radially attached to the antenna support portion 32 so that the bottom portion of the U-shape faces the wall surface side of the vacuum container 31. Further, all of the high-frequency antennas 33 are connected in parallel via one power amplifier and one power source (not shown).

A load lock chamber 38 is provided on one of the side walls of the eight faces of the vacuum container 31. The loading lock chamber 38 is provided with a vacuum container side loading and unloading port 381 for carrying out the loading and unloading of the substrate 22 to be processed between the inner space 311 and the outer side loading and unloading port 382 for external use. The substrate to be processed 22 is carried out and carried in between, and the inside thereof can be exhausted independently of the internal space 311 of the vacuum vessel 31. In the internal space 311, a base conveyance device (not shown) that winds the substrate to be processed 22 carried in from the loading lock chamber 38 around the side wall is provided.

Further, as in the first embodiment, a vacuum pump or a gas introduction port or the like is provided.

The operation of the plasma processing apparatus 30 of the present embodiment will be described. As in the first embodiment, plasma is generated in the internal space 311. Then, the substrate to be processed 22 is sequentially carried into the internal space 311 from the outside via the loading lock chamber 38, and is plasma-treated at a predetermined time around the internal space 311 by the substrate conveyance device. The substrate to be processed 22 that has reached the load lock chamber 38 is carried out from the vacuum container side carry-out port 381 to the load lock chamber 38, and after the door of the vacuum container side carry-in port 381 is closed, the outer side carry-in port 382 is opened and carried out to the outside. Then, the next substrate to be processed 22 is carried into the loading lock chamber 38, and is carried into the internal space 311 in the reverse order. In this manner, the plurality of substrates to be processed 22 are sequentially subjected to plasma treatment in sequence.

Since the plasma processing apparatus 30 of the present embodiment performs the loading and unloading of the substrate to be processed 22 while the plasma is still generated in the internal space 311, the plasma processing is not interrupted, and the plurality of plasma processing apparatuses can be processed efficiently and continuously. The substrate is processed. Further, all of the substrates 22 to be processed can be subjected to plasma treatment under the same conditions.

[Third embodiment]

The plasma processing apparatus 40 of the third embodiment will be described using the top view shown in Fig. 4. The plasma processing apparatus 40 of the present embodiment is a device for performing plasma treatment on the surface of the film-form substrate to be processed 23 composed of a strip-shaped film.

The plasma processing apparatus 40 of the present embodiment has a rectangular parallelepiped vacuum container 41, and a hexagonal column-shaped antenna is provided so as to protrude from the vicinity of the center of the upper wall surface into the internal space 411 of the vacuum vessel 41 (plasma generation means) The support unit 42. Further, similarly to the plasma processing apparatus 30 of the second embodiment, the antenna support unit 42 is provided with the radio-frequency antenna 43 and is connected in parallel via a power amplifier and a power source (not shown).

The film-form substrate holding portion 46 is provided to surround the antenna support portion 42. The film-form substrate holding portion 46 has a large cylindrical roller 461 parallel to the antenna supporting portion 42 and a cylindrical small roller 462 which is parallel to the antenna supporting portion 42 and has a smaller diameter than the large roller 461. Around the antenna support portion 42, there is 60. A total of six large rolls 461 are arranged at intervals. A total of twelve small rolls 462 of each pair are disposed on the outer circumference of each of the large rolls 461. Further, on the side of the adjacent two large rollers 461, a delivery portion 471 and an intake portion 472 composed of a cylindrical roller are provided in parallel with the antenna support portion 42.

Further, as in the first and second embodiments, a vacuum pump or a gas introduction port or the like is provided.

The operation of the plasma processing apparatus 40 will be described. First, the film-form substrate to be processed 23 wound around the delivery portion 471 is attached to the film-form substrate holding portion 46 and the take-in portion 472 as follows. First, the first small roller 462A adjacent to the delivery portion 471, the first large roller 461A adjacent to the first small roller 462A, and the second small roller adjacent to the first large roller 461A and the first small roller 462A. The 462B, ..., and the 12th small roller 462L adjacent to the take-in portion 472 are placed in a sequence. Then, one end of the film-form substrate to be processed 23 is fixed to the take-in portion 472.

Next, after the air in the internal space 411 is removed by a vacuum pump, a plasma material gas is introduced from the gas introduction port, and a high-frequency alternating current is introduced from the power source to the high-frequency antenna 43, thereby generating plasma in the internal space 411. At the same time, the film-shaped substrate to be processed 23 is taken in from the delivery portion 471 via the film-form substrate holding portion 46 by the take-in portion 472 by rotating the roller of the take-in portion 472. During this period, the surface (processed surface) of one of the film-formed substrates 23 is exposed to the plasma, and thus plasma treatment such as etching or deposition is applied to the surface to be treated.

According to the plasma processing apparatus of the third embodiment, the plasma treatment can be performed on the entire surface of the surface to be processed. At that time, since the film-form substrate to be processed 23 is sequentially moved, the treatment on the surface of the film-form substrate 23 can be uniformly performed. Further, since the high-frequency antenna 43 is surrounded by the film-formed substrate 23, the generated plasma is also surrounded by the film-form substrate 23, and as a result, the plasma can be used for the film-form substrate 23 without waste. deal with.

Also in the third embodiment, the shape, the number, the position, and the like of the antenna supporting portion 42 or the radio-frequency antenna 43 can be appropriately changed as in the first embodiment.

10. . . Plasma processing apparatus of the first embodiment

11, 31, 41. . . Vacuum container

111, 311, 411. . . Internal space

12, 32, 42. . . Antenna support unit (plasma generation means support unit)

13, 33, 43. . . High frequency antenna (plasma generation means)

14. . . power supply

15. . . Impedance integrator

16. . . Base holding unit

161. . . Revolution

162. . . Rotation

163. . . pillar

twenty one. . . Processed substrate

twenty three. . . Film-like treated substrate

30. . . Plasma processing apparatus of the second embodiment

38. . . Loading lock room

381. . . Vacuum container side loading and unloading

382. . . External side loading and unloading

40. . . Plasma processing apparatus of the third embodiment

46. . . Film-like substrate holding portion

461. . . Large roller

462. . . Small roller

471. . . Delivery department

472. . . Take-in department

Fig. 1 is a longitudinal cross-sectional view showing a plasma processing apparatus including a base holding portion including a rotation portion and a revolution portion according to the first embodiment of the present invention.

Fig. 2 is a top view showing the plasma processing apparatus of the first embodiment.

Fig. 3 is a top view showing a plasma processing apparatus 30 having a loading lock chamber 38 and a base conveying device according to a second embodiment of the present invention.

Fig. 4 is a top plan view showing a plasma processing apparatus 40 having a film-form substrate holding portion according to a third embodiment of the present invention.

10. . . Plasma processing device

11. . . Vacuum container

12. . . Antenna support

13. . . High frequency antenna

14. . . power supply

15. . . Impedance integrator

16. . . Base holding unit

twenty one. . . Processed substrate

111. . . Internal space

161. . . Revolution

162. . . Rotation

163. . . pillar

Claims (7)

A plasma processing apparatus, comprising: a) a vacuum container; b) a plasma generating means supporting portion disposed to protrude into an inner space of the vacuum container; c) one or a plurality of plasma generating means, The plasma generating means supporting portion is an inductive coupling type high frequency antenna; and d) a base holding portion that holds the plurality of processed substrates to surround the plasma generating means supporting portion. The plasma processing apparatus according to claim 1, wherein the plurality of plasma generating means are radially disposed from the plasma generating means supporting portion to the wall surface of the vacuum container. A plasma processing apparatus according to claim 1, wherein the base holding portion includes a revolving portion that rotates the substrate to be processed around the plasma generating means supporting portion. A plasma processing apparatus according to claim 1, wherein the base holding portion includes a rotating portion that rotates the substrate to be processed. A plasma processing apparatus, comprising: a) a vacuum container; b) a plasma generating means supporting portion disposed to protrude into an inner space of the vacuum container; c) one or a plurality of plasma generating means Mounted on the surface of the plasma generating means support portion, the plasma generating means is an inductively coupled high frequency And a film-form substrate holding portion that holds the film-form substrate such that the film-form substrate surrounds the plasma generating means supporting portion. The plasma processing apparatus of claim 5, comprising: a delivery portion that sequentially feeds the strip-shaped film-like substrate to the film-form substrate holding portion; and the take-in portion is held from the film-like substrate The film-like substrate is sequentially taken in. A plasma processing apparatus according to claim 1, which comprises loading a lock chamber for carrying in/out the substrate to be processed between the vacuum container and the outside of the vacuum container.