JP4776560B2 - Vacuum processing equipment - Google Patents

Description

  The present invention relates to the technical field of vacuum processing equipment.

  Conventionally, when generating plasma inside a vacuum chamber and performing film formation processing, an electrostatic adsorption device that adsorbs a substrate with electrostatic adsorption force to hold the substrate on the substrate holder, and adsorbs the substrate with magnetic force For example, a vacuum suction device that vacuum-sucks a magnet or a substrate on a suction port is used.

  However, when using a vacuum suction device, the substrate has a difference in heat distribution, capacitance, etc. between the part above the suction port and the other part, and as a result, the part above the suction port and the other part A difference occurs in the plasma density.

Also, when using an electrostatic adsorption device, a difference occurs in plasma density due to an electric field, and when using a magnet, a difference occurs in plasma density due to magnetic force.
When the plasma density is biased, the CVD apparatus has a disadvantage that the film thickness distribution of the thin film grown on the substrate surface is deteriorated.

Further, when the electrostatic chucking device is used, there is a problem in that the insulating plate of the electrostatic chucking device breaks when the element on the substrate is electrostatically destroyed or the substrate being processed is heated to a high temperature.
JP 2001-284332 A JP 2002-365646 A

  The present invention has been made to solve the above-mentioned problems, and its object is to provide a vacuum processing apparatus capable of processing the substrate surface uniformly without damaging the substrate and the suction device. is there.

In order to solve the above problems, the present invention is a vacuum processing apparatus comprising: a vacuum chamber; a substrate holder disposed inside the vacuum chamber; and a mask disposed on the substrate disposed on the substrate holder. The mask is formed larger than the substrate, the substrate holder is formed with a suction port connected to a suction mechanism, and the suction port is arranged so that the mask protrudes from the edge of the substrate A vacuum processing apparatus sometimes adapted to face a portion of the substrate holder that protrudes from an edge of the substrate of the substrate holder.
The present invention is a vacuum processing apparatus, wherein the suction port is a ring-shaped vacuum processing apparatus.
The present invention is a vacuum processing apparatus, wherein a concave portion is formed on a surface of the substrate holder, the substrate is arranged inside the concave portion, and the suction port is formed on the surface of the substrate holder. This is a vacuum processing apparatus arranged outside the opening.

  Since the present invention is configured as described above and the suction port is formed so as to directly face the mask, when the gas on the suction port is sucked by the suction mechanism, the mask is vacuum-adsorbed. Since the substrate is disposed between the mask and the substrate holder, the mask is pressed toward the substrate when it is vacuum-sucked, and the mask and the substrate are brought into close contact with each other. Therefore, the mask and the substrate are not misaligned.

  A suction port is not formed at a position facing the back surface of the substrate, and the substrate is not vacuum-sucked, so that there is no bias in heat distribution, capacitance, or the like. Therefore, when plasma is generated inside the vacuum chamber, the plasma density on the substrate surface becomes uniform.

  Devices on the board are not electrostatically destroyed. Since the plasma distribution on the substrate surface is not biased, the substrate surface is uniformly treated with plasma. In the case of a CVD apparatus, a thin film having a uniform thickness is formed, and in the case of a cleaning apparatus, uneven cleaning does not occur.

Reference numeral 10 in FIG. 1 shows an example of the vacuum processing apparatus of the present invention.
The vacuum processing apparatus 10 includes a vacuum chamber 11, a substrate holder 30, a mask 20, and a suction mechanism 9. The substrate holder 30 is provided inside the vacuum chamber 11. Reference numeral 32 in FIG. 1 denotes a placement surface on which the substrate of the substrate holder 30 is placed.
A groove 33 is formed on the mounting surface 32. A focusing tube 36 and a plurality of connecting tubes 37 are installed inside the substrate holder 30. Each connection pipe 37 has one end connected to the bottom surface of the groove 33 and the other end connected to the focusing pipe 36.

2 indicates a connection port which is one end of the connection pipe 37 connected to the bottom surface or side surface of the groove 33.
The suction mechanism 9 is disposed outside the vacuum chamber 11, and the focusing tube 36 is connected to the suction mechanism 9. When the suction mechanism 9 is operated, the gas inside the groove 33 is connected from the connection port 38 to the connection tube 37. The air is exhausted to the suction mechanism 9 through the focusing tube 36.

  Since the opening of the groove 33 is exposed to the mounting surface 32 and the internal space of the groove 33 is connected to the external space of the substrate holder 30 by the opening, when the internal space of the groove 33 is exhausted, the opening is The suction port 34 is used to exhaust the gas on the mounting surface 32.

Here, the groove 33 has a ring shape in plan view. The substrate 7 to be processed by the vacuum processing apparatus 10 is smaller than the inner ring periphery of the groove 33, and the substrate 7 arranged inside the vacuum chamber 11 is arranged inside the ring 33 of the groove 33 of the mounting surface 32. The
Accordingly, the groove 33 is disposed outside the edge of the substrate 7 and along the edge of the substrate 7.

  The mask 20 has a shielding plate 21 and a through hole 22 formed in the shielding plate 21. If a region to be processed by the vacuum processing apparatus 10 on the surface of the substrate 7 is a processing region, the shape and location of the processing region are determined in advance.

  The shape of the through hole 22 is substantially equal to the shape of the processing region, and the planar shape and size of the shielding plate 21 are the same as or larger than the ring outer periphery of the groove 33, and the through hole 22 is formed in the processing region. When the mask 20 is arranged on the surface of the substrate 7 so as to be positioned directly above, the outer periphery of the shielding plate 21 coincides with the outer periphery of the ring of the groove 33 or the entire outer periphery of the shielding plate 21 is larger than the outer periphery of the ring of the groove 33. It protrudes outward (FIG. 2).

As described above, since the substrate 7 is arranged inside the ring of the groove 33, there is no substrate 7 above the groove 33, so the suction port 34 is not formed below the substrate 7, and the shielding plate 21. The edge portion protruding from the substrate 7 directly faces the suction port 34.
Here, since the mounting surface 32 is flattened and the mask 20 is disposed on the surface of the substrate 7 on the mounting surface 32, the shielding plate 21 of the mask 20 does not contact the mounting surface 32, and the shielding plate 21. And a suction port 34.

  Since the height of the gap 39 from the suction port 34 to the shielding plate 21 is only about the thickness of the substrate 7, even if gas enters the gap 39 from the processing space outside the gap 39, the conductance of the amount of entry The pressure in the inner space of the groove 33 and the gap 39 is lower than that in the processing space. If there is a pressure difference between the processing space and the gap 39, the shielding plate 21 is attracted toward the suction port 34 by the differential pressure.

  Further, when the substrate 7 is thin and the shielding plate 21 is attracted to and bent by the suction port 34 and comes into contact with the placement surface 32, the gap 39 connecting the suction port 34 to the processing space is eliminated. When the gap 39 disappears, gas does not enter from the processing space, and the pressure difference between the processing space and the groove 33 becomes larger, so that the force with which the shielding plate 21 is adsorbed becomes stronger.

  As described above, since the mask 20 is disposed on the surface of the substrate 7 and there is a gap 39 before being sucked by the suction port 34, when the shielding plate 21 is sucked, the force of the shielding plate 21 toward the substrate holder 30. Acts, and the mask 20 is pressed toward the substrate 7 to be brought into close contact therewith.

  No groove or opening is formed at the place where the substrate 7 is placed on the mounting surface 32. When the mask 20 is in close contact with the substrate 7, the substrate 7 is pressed against the substrate holder 30, and the entire back surface of the substrate 7 is placed. Closely contacts the mounting surface 32.

  Here, the ring shape of the groove 33 and the shape of the substrate 7 are each rectangular, and the shielding plate 21 protrudes from the four sides and four corners of the substrate 7 and from the four sides and four corners of the groove 33, respectively. Therefore, since the shielding plate 21 protrudes from the entire outer periphery of the substrate 7 and the suction port 34 faces the shielding plate 21 over the entire circumference, the force that the mask 20 is attracted is generated along the entire circumference of the substrate 7. The state in which the substrate 7 and the mask 20 are in close contact with each other is stably maintained.

Next, a process of processing the substrate 7 using the vacuum processing apparatus 10 will be described.
Here, the vacuum processing apparatus 10 is a CVD apparatus, and a shower head 13 is disposed inside the vacuum chamber 11.
A vacuum exhaust system 19 and a gas supply system 15 are disposed outside the vacuum chamber 11, the vacuum exhaust system 19 is connected to the vacuum chamber 11, and the gas supply system 15 is connected to the shower head 13.

  The inside of the vacuum chamber 11 is evacuated by the evacuation system 19 to form a high vacuum atmosphere. The vacuum chamber 11 is connected to a transfer chamber (not shown), and carries the substrate 7 from the transfer chamber into the vacuum chamber 11 while maintaining a high vacuum atmosphere inside the vacuum chamber 11. Here, a mask 20 is accommodated in advance in the vacuum chamber 11, and the mask 20 and the loaded substrate 7 are aligned and placed on the mounting surface 32 as described above.

While continuing to evacuate the inside of the vacuum chamber 11, the gas on the suction port 34 is exhausted by the suction mechanism 9, the plasma gas and the source gas are introduced from the gas supply system 15 to the shower head 13, and the plasma gas and the source gas are evacuated. The pressure in the vacuum chamber 11 is set to a pressure of 0.1 Torr or more and 700 Torr or less (1.333 × 10 Pa or more and 9.333 × 10 ⁴ Pa or less), and the pressure is maintained. Here, “Torr” and “Pa” are written together, but if there is an error when the value of “Torr” is converted to “Pa”, the value of “Torr” is given priority.

  As described above, when the gas on the suction port 34 is exhausted, the pressure in the internal space of the groove 33 and the gap 39 decreases to near zero. Since the pressure in the processing space is maintained at 1.333 × 10 Pa or more, a pressure difference of 1.333 × 10 Pa or more is generated between the groove 33 and the processing space, and the shielding plate 21 is sucked by the pressure difference. The substrate 7 and the mask 20 are in close contact with each other by being sucked by the mouth 34.

  Here, the shower head 13 is connected to the power source 5, and the vacuum chamber 11 and the substrate holder 30 are placed at the same ground potential while the pressure of the processing space is kept at the set pressure, so that the shower head 13 is connected to the shower head 13. When a voltage is applied, plasma of a plasma gas and a source gas is generated, and a thin film of a reactant of the source gas grows in a processing region on the surface of the substrate 7.

  The focusing tube 36 and the connecting tube 37 described above are so deep from the placement surface 32 that the plasma on the surface of the substrate 7 is not affected. Further, since there are no suction holes or openings on the back surface of the substrate 7 and the entire back surface of the substrate 7 is in close contact with the mounting surface 32, a thin film that grows on the surface of the substrate 7 without causing a bias in plasma density on the surface of the substrate 7. Makes the film thickness uniform.

If the vacuum suction of the mask 20 is continued at least during the film formation, the mask 20 and the substrate 7 are not misaligned, so that a thin film grows in a predetermined region on the surface of the substrate 7.
When the film thickness grows to a predetermined film thickness, the voltage application to the shower head 13 is stopped and the gas supply from the gas supply system 15 is stopped.

When the supply of gas is stopped, the exhaust by the suction mechanism 9 and the exhaust by the vacuum exhaust system 19 are continued, and the pressure in the processing space is set to a high vacuum of less than 1.333 × 10 Pa. The difference is less than 1.333 × 10 Pa (near zero), and the mask 20 and the substrate 7 after film formation can be lifted from the substrate holder 30, and the substrate after film formation can be carried out of the vacuum chamber 11. .
Although the above has described the case where the mounting surface 32 is flat, the present invention is not limited to this.

  The code | symbol 40 of FIG. 3 has shown the board | substrate holder of the 2nd example of this invention. This substrate holder 40 has the same configuration as the substrate holder 30 of FIGS. 1 and 2 except that a recess 49 is formed inside the region where the groove 33 of the mounting surface 42 is formed. The same members as those of the second substrate holder 30 will be described with the same reference numerals.

  The planar shape of the recess 49 is larger than that of the substrate 7, and the substrate 7 is disposed in the recess 49. The depth from the opening of the concave portion 49 to the bottom surface is the same as or smaller than the thickness of the substrate 7. After the alignment, when the mask 20 is lowered from the concave portion 49, the back surface of the shielding plate 21 is the surface of the substrate 7. However, it does not contact the mounting surface 42 and a gap is formed between the shielding plate 21 and the mounting surface 42.

Even if the thickness of the substrate 7 is large, the height of the gap is reduced by the depth of the concave portion 49. Therefore, when the shielding plate 21 is adsorbed and bent, the depth of the concave portion 49 is in close contact with the mounting surface 42. Is set, the force for attracting the mask 20 is increased.
Although the case where the connection port 38 of the connection pipe 37 is connected to the bottom surface of the groove 33 has been described above, the present invention is not limited to this.

  Reference numeral 50 in FIG. 4 shows a third example of the substrate holder used in the present invention. The substrate holder 50 has the same configuration as the substrate holder 30 of FIG. 2 except that the mounting surface is not provided with a groove and the connection port 54 of the connection pipe 57 is flush with the mounting surface. ing. Similar to the substrate holder 30 of FIG. 2, the connection tube 57 is connected to the suction mechanism 9 via the focusing tube 36. Therefore, in the substrate holder 50 of the third example, the connection port 54 is a gas on the mounting surface. It becomes the suction port 34 which exhausts air.

  Here, the connection pipe 57 includes a ring-shaped exhaust pipe 55, a branch pipe 58 that connects the exhaust pipe 55 to the focusing pipe 36, a plurality of ends that are connected to the exhaust pipe 55, and the other ends are exposed on the mounting surface. The external connection pipe (not shown) is included, and the connection port 54 is configured by an end opening that is exposed on the mounting surface of the external connection pipe.

The connection ports 54 are arranged outside the area where the substrate 7 is placed on the mounting surface and spaced along the edge of the area. Here, the substrate 7 is rectangular, and when the substrate 7 is disposed on the mounting surface, one or more connection ports 54 are positioned in the vicinity of the four sides of the substrate 7. Accordingly, the force that the mask 20 is vacuum-sucked is generated at positions near the four sides of the substrate 7, so that the substrate 7 is stably held by the substrate holder 50.
Although the above has described the case where the vacuum processing apparatus 10 of the present invention is used for CVD film formation, the present invention is not limited to this.

The present invention can be widely used for applications in which the internal pressure of the vacuum chamber 11 is set to 1.333 × 10 Pa or more. When the gas supplied into the vacuum chamber 11 is switched from the source gas to the cleaning gas and the cleaning gas plasma is generated, the deposits on the inner wall surface of the vacuum chamber 11 are removed and the deposits on the mask 20 are also removed. Is done. Therefore, a cleaning chamber for cleaning the mask 20 is not necessary.
Further, the mask 20 can be carried in from the outside of the vacuum chamber 11 together with the substrate 7 without being accommodated in the vacuum chamber 11 in advance.

  A plastic substrate having a weight of 20 kg was placed on the mounting surface 32 of the substrate holder 30 in FIG. 1, and the suction port 34 was directly opposed to the edge of the plastic substrate. While the pressure inside the vacuum chamber 11 was kept equal to the atmospheric pressure, the gas on the suction port 34 was exhausted by the suction mechanism 9 to adsorb the plastic substrate.

  When the substrate holder 30 was tilted so that the angle between the mounting surface 32 and the horizontal surface was 45 °, whether or not the plastic substrate dropped from the mounting surface 32 was examined by changing the internal pressure of the groove 33. The results are listed in Table 1 below.

The “pressure difference” in Table 1 is a value obtained by subtracting the internal pressure of the groove 33 from the atmospheric pressure (internal pressure of the vacuum chamber 11).
As is clear from Table 1 above, when the pressure difference was 0.1 Torr (1.333 × 10 Pa) or more, the plastic substrate was held on the substrate holder 30 without falling off.

  From the above, it can be seen that if the difference between the pressure in the internal space of the vacuum chamber 11 and the pressure in the groove 33 is 1.333 × 10 Pa or more, the adsorbing force when the mask is brought into close contact with the substrate is strong. .

Sectional drawing for demonstrating an example of the vacuum processing apparatus of this invention Plan view for explaining the substrate holder of the first example Sectional drawing for demonstrating the substrate holder of a 2nd example Plan view for explaining the substrate holder of the third example

Explanation of symbols

  7 ... Substrate 10 ... Vacuum processing device 20 ... Mask 30, 40, 50 ... Substrate holder 34, 54 ... Suction port 39 ... Suction mechanism

Claims (3)

A vacuum chamber;
A substrate holder disposed inside the vacuum chamber;
A mask disposed on a substrate disposed on the substrate holder,
The mask is formed larger than the substrate;
The substrate holder is formed with a suction port connected to a suction mechanism,
The vacuum processing apparatus, wherein the suction port faces a portion of the substrate holder that protrudes from the edge of the substrate when the mask is arranged to protrude from the edge of the substrate.   The vacuum processing apparatus according to claim 1, wherein the suction port is formed in a ring shape. A recess is formed on the surface of the substrate holder,
The substrate is disposed inside the recess;
The vacuum processing apparatus according to claim 1, wherein the suction port is disposed outside the opening of the concave portion on the surface of the substrate holder.

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