JP2005097640A - Vacuum deposition system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vacuum deposition system capable of reducing the difference in the angles of incidence of vapor deposition flows between the central part and the outer circumferential part of the substrate to be treated as possible without upsizing a vacuum chamber. <P>SOLUTION: The vacuum deposition system 101 is provided with: a vacuum chamber 2; a vacuum pump 3; a substrate holder 5 holding a semiconductor substrate 4; a substrate holder rotation mechanism 102 rotating the substrate holder 5 with an axis as the center; four vapor deposition boats 103a to 103d storing vapor deposition materials 6 of the same kind; four electron guns 104a to 104d emitting electron beams 8; a shutter 11 releasing/shielding vapor deposition flows 10 from the four vapor deposition materials 6; and a collimator plate 105 arranged between the semiconductor substrate 4 and the vapor deposition materials 6 and allowing only the vapor deposition flows 10 with fixed small angles θ of incidence to the semiconductor substrate 4 to pass separately from the shutter 11. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vacuum evaporation apparatus for forming a film by evaporating a deposition material in a vacuum and depositing it on a surface of a substrate to be processed.

  FIG. 4 shows a longitudinal sectional view of an example of a conventional vacuum deposition apparatus.

  The vacuum deposition apparatus 1 is disposed in a vacuum chamber 2 capable of maintaining the inside in a high vacuum state, a vacuum pump 3 that exhausts the inside of the vacuum chamber 2 to a high vacuum, and a vacuum chamber 2 as a substrate to be processed. For example, a substrate holder 5 that holds the semiconductor substrate 4, a vapor deposition boat 7 that is disposed opposite to the substrate holder 5 and contains the vapor deposition raw material 6, and an electron beam 8 as a heating means for heating the vapor deposition raw material 6 (in the drawing). An electron gun 9 that emits a broken line arrow, a focusing coil (not shown) and a deflection coil (not shown) for applying a magnetic force for focusing and deflecting the electron beam 8, and a deposition flow 10 ( The shutter 11 emits or blocks a solid arrow).

  Here, the shutter 11 rotates and moves above the vapor deposition material 6 so as to block the vapor deposition flow 10 and retreats from the vapor deposition material 6 to a predetermined standby position to discharge the vapor deposition flow 10. FIG. 4 shows a state in which the shutter 11 is retracted and the vapor deposition flow 10 is released.

  Next, operation | movement of the vacuum evaporation system 1 is demonstrated. First, the semiconductor substrate 4 is held on the substrate holder 5 and the vacuum pump 3 is operated to reduce the pressure in the vacuum chamber 2 to a desired degree of vacuum.

  Next, when the inside of the vacuum chamber 2 reaches a desired degree of vacuum, an electron beam 8 is emitted from the electron gun 9, and the electron beam 8 is focused and focused by a focusing coil (not shown) and a deflection coil (not shown). It deflects and irradiates the surface of the deposition material 6 substantially perpendicularly, and the deposition material 6 is heated and dissolved.

  First, a so-called gas out operation is performed for the purpose of evaporating impurities on the surface of the deposition material 6 and making the surface state uniform. This gas discharge operation is performed with the shutter 11 in the shut-off state.

  Thereafter, when the gas out operation is completed, the shutter 11 is released, and the vapor deposition flow 10 is discharged toward the surface of the semiconductor substrate 4 to perform a predetermined film formation.

Next, when the film formation is completed, at that time, the shutter 11 is turned off and the electron gun 9 is stopped to complete the film formation (see, for example, Patent Document 1).
JP 2001-271157 (2nd page, paragraph 0003, FIG. 2)

  In the above description, the heating method using the electron beam 8 has been described as the heating method for the vapor deposition material 6, but a heating method such as resistance heating or high-frequency heating may be used.

  However, in the conventional vacuum vapor deposition apparatus 1 as described above, since the vapor deposition flow 10 is emitted radially from the vapor deposition raw material 6 having a relatively small area to the surface of the semiconductor substrate 4, the central portion and the outer periphery of the semiconductor substrate 4 inevitably. There is a difference between the incident angle θ of the vapor deposition flow 10 (the angle formed by the normal to the surface of the semiconductor substrate 4 and the vapor deposition flow 10).

  That is, the incident angle θ of the vapor deposition flow 10 near the center of the semiconductor substrate 4 directly above the vapor deposition raw material 6 is approximately 0 °, but the incident angle θ of the vapor deposition flow 10 on the outer periphery of the semiconductor substrate 4 is not negligible. As a result, the thickness near the center of the semiconductor substrate 4 tends to be thick, and the outer peripheral portion of the semiconductor substrate 4 tends to be thin. And this tendency became remarkable with the enlargement of the semiconductor substrate 4 size.

  On the other hand, if the incident angle θ of the vapor deposition flow 10 with respect to the semiconductor substrate 4 is to be reduced as a whole, for example, the distance between the semiconductor substrate 4 (substrate holder 5) and the vapor deposition raw material 6 (vapor deposition boat 7) is increased as much as possible. do it. However, if the distance between the semiconductor substrate 4 (substrate holder 5) and the vapor deposition material 6 (vapor deposition boat 7) is increased, the vacuum chamber 2 itself is enlarged, resulting in a decrease in film formation rate. This resulted in an increase in evacuation time.

  An object of the present invention is to provide a vacuum deposition apparatus capable of minimizing the difference in the incident angle of the deposition flow between the central portion and the outer peripheral portion of the substrate to be processed without increasing the size of the vacuum chamber.

The vacuum deposition apparatus of the present invention is
at least,
A vacuum chamber capable of maintaining a high vacuum inside;
A vacuum pump that evacuates the vacuum chamber to a high vacuum;
A substrate holder disposed in a vacuum chamber and holding a substrate to be processed;
A plurality of vapor deposition boats arranged opposite to the substrate holder and containing the same kind of vapor deposition raw materials,
Heating means for generating a vapor deposition flow by heating vapor deposition raw materials in a plurality of vapor deposition boats;
A shutter that is disposed between the substrate to be processed and the deposition raw material, and that releases and blocks the deposition flow;
Separately from the shutter, a collimator plate is disposed between the substrate to be processed and the vapor deposition raw material, and allows only the vapor deposition flow that is incident on the substrate to be processed at a constant small incident angle to pass through the vapor deposition flow. A vacuum vapor deposition apparatus characterized in that a film is deposited on a substrate to be processed.

  According to the vacuum vapor deposition apparatus of the present invention, a plurality of vapor deposition boats containing the same type of vapor deposition raw material are arranged facing the substrate to be processed, so that compared to the case where the vapor deposition flow is discharged from one vapor deposition raw material, A plurality of substantially vertical vapor deposition flows can be discharged with respect to the substrate, and further, a collimator plate that allows only the vapor deposition flow having a constant small incident angle to pass through the substrate to be processed is disposed, so that the vacuum chamber is not enlarged. The difference in the incident angle of the vapor deposition flow between the central portion and the outer peripheral portion of the substrate to be processed can be reduced.

  For the purpose of providing a vacuum deposition apparatus having a function capable of reducing the difference in the incident angle of the deposition flow between the central portion and the outer peripheral portion of the substrate to be processed without increasing the size of the vacuum chamber, the same kind of deposition raw materials are accommodated. This was realized by arranging a plurality of vapor deposition boats facing the substrate to be processed, and further arranging a collimator plate that allows only a vapor deposition flow having a small incident angle to pass.

  An example of the vacuum deposition apparatus of the present invention is shown in FIGS. FIG. 1 is a vertical cross-sectional view, and FIG. 2 is a cross-sectional view taken along the line XX of FIG. 1 and is a schematic diagram showing the arrangement of the evaporation boat with respect to the collimator plate. The same parts as those in FIG. 4 are denoted by the same reference numerals.

  The vacuum deposition apparatus 101 is disposed in the vacuum chamber 2 capable of maintaining the inside thereof in a high vacuum state, the vacuum pump 3 that exhausts the inside of the vacuum chamber 2 to a high vacuum, and the vacuum chamber 2 as a substrate to be processed. For example, the substrate holder 5 that holds the semiconductor substrate 4, the rotation shaft 102 a and the rotation motor 102 b as the substrate holder rotation mechanism 102 that rotates the substrate holder 5 about the axis, and the substrate holder 5 are opposed to each other. For example, four vapor deposition boats 103a, 103b, 103c, and 103d that are arranged and contain the same kind of vapor deposition raw materials 6 and heating means for heating the vapor deposition raw materials 6 in the respective vapor deposition boats 103a to 103d are provided. 4 electron guns 104a, 104b, 104c, 104d for emitting electron beams 8 (broken arrows in the figure), and each electron beam 8 A focusing coil (not shown) and a deflection coil (not shown) for applying a magnetic force for bundling and deflecting, and a deposition flow 10 (solid arrows in the figure) from the four deposition raw materials 6 are released or blocked. Separately from the shutter 11 and the shutter 11, the shutter 11 is disposed between the semiconductor substrate 4 and the vapor deposition material 6, and passes only the vapor deposition flow 10 having a certain small incident angle θ with respect to the semiconductor substrate 4. And a collimator plate 105 which is a feature of the present invention.

  Here, the four vapor deposition boats 103 a to 103 d are equally arranged in the diameter direction of the semiconductor substrate 4.

  As shown in FIG. 2, the collimator plate 105 is provided with a large number of circular openings 105a in a predetermined arrangement pattern, and each of the vapor deposition flows 10 from the four vapor deposition raw materials 6 (solid arrows in the figure). ), Only the vapor deposition flow 10 having a certain small incident angle θ can pass through the semiconductor substrate 4.

  Further, the distance L of the collimator plate 105 from the surface of the semiconductor substrate 4 can be varied by a support shaft 106a as the collimator plate height adjusting mechanism 106 and a drive motor 106b, and the magnitude of the incident angle θ of the vapor deposition flow 10 with respect to the semiconductor substrate 4. Can be controlled.

  Further, the shutter 11 rotates and moves above the vapor deposition material 6 so as to block the vapor deposition flow 10 and retreats from the vapor deposition material 6 to a predetermined standby position to discharge the vapor deposition flow 10. FIG. 1 shows a state where the shutter 11 is retracted and the vapor deposition flow 10 is released.

  Next, operation | movement of the vacuum evaporation system 101 is demonstrated. First, the semiconductor substrate 4 is held on the substrate holder 5 and the vacuum pump 3 is operated to reduce the pressure in the vacuum chamber 2 to a desired degree of vacuum.

  Next, when the inside of the vacuum chamber 2 reaches a desired degree of vacuum, an electron beam 8 is emitted from the electron guns 104a to 104d, and this electron beam 8 is emitted by a focusing coil (not shown) and a deflection coil (not shown). Focusing and deflecting are performed, and the surface of the vapor deposition raw material 6 in each of the vapor deposition boats 103a to 103d is irradiated substantially perpendicularly to melt the vapor deposition raw material 6 by heating.

  First, a so-called gas out operation is performed for the purpose of evaporating impurities on the surface of the deposition material 6 and making the surface state uniform. This gas discharge operation is performed with the shutter 11 in the shut-off state.

  Thereafter, when the gas discharge operation is completed, the substrate holder rotating mechanism 102 is operated to rotate the substrate holder 5 about the axis. By this rotational movement, the vapor deposition flow 10 that has passed through the collimator plate 105 can be more uniformly deposited on the surface of the semiconductor substrate 4.

  Then, the shutter 11 is released, and the vapor deposition flow 10 is emitted toward the surface of the semiconductor substrate 4 to perform a predetermined film formation. In addition, the position (distance L) of the collimator plate 105 is adjusted in advance to a position where the desired incident angle θ of the vapor deposition flow 10 can be obtained by the collimator plate height adjustment mechanism 106.

  In the above description, the heating method using the electron beam 8 has been described as the heating method for the vapor deposition material 6, but a heating method using resistance heating, high-frequency heating, or the like may be used.

  In the above description, the four vapor deposition boats 103a to 103d are described as being arranged in the diameter direction, but the number and arrangement of the vapor deposition boats are not limited to this, and as a modification, for example, FIG. As shown in a), the three vapor deposition boats 103a to 103c may be arranged in the diametrical direction, and as shown in FIG. 3B, the four vapor deposition boats 103a to 103d are respectively disposed on the semiconductor substrate. A configuration in which one at the center of 4 and the remaining three are evenly arranged on the concentric circles may be employed, and can be appropriately changed so as to obtain a desired film thickness distribution. Similarly, the shape, dimensions, and arrangement pattern of the openings 105a of the collimator plate 105 are not particularly limited, and can be appropriately changed so as to obtain a desired film thickness distribution.

  The present invention can be applied to a vacuum deposition apparatus having a function capable of minimizing the difference in the incident angle of the deposition flow between the central portion and the outer peripheral portion of the substrate to be processed.

The longitudinal cross-sectional view of an example of the vacuum evaporation system of this invention Schematic diagram showing the arrangement of the evaporation boat with respect to the collimator plate Schematic diagram of a variation of the arrangement of the evaporation boat relative to the collimator plate A longitudinal sectional view of an example of a conventional vacuum evaporation system

Explanation of symbols

1 Conventional vacuum evaporation system 2 Vacuum chamber
DESCRIPTION OF SYMBOLS 3 Vacuum pump 4 Semiconductor substrate 5 Substrate holder 6 Deposition raw material 7 Deposition boat 8 Electron beam 9 Electron gun 10 Deposition flow 11 Shutter 101 Vacuum deposition apparatus 102 of the present invention 102 Substrate holder rotating mechanism 102a Rotating shaft 102b Rotating motor 103a-103d Four pieces Deposition boats 104a to 104d Four electron guns 105 Collimator plate 105a Opening 106 Collimator plate height adjustment mechanism 106a Support shaft
106b Drive motor θ Incident angle L Distance of collimator plate from semiconductor substrate surface

Claims (5)

at least,
A vacuum chamber capable of maintaining a high vacuum inside;
A vacuum pump for evacuating the vacuum chamber to a high vacuum;
A substrate holder disposed in the vacuum chamber and holding a substrate to be processed;
A plurality of vapor deposition boats arranged facing the substrate holder and containing the same kind of vapor deposition raw materials,
Heating means for generating a vapor deposition flow by heating vapor deposition materials in the plurality of vapor deposition boats;
A shutter that is disposed between the substrate to be processed and the vapor deposition material, and releases or blocks the vapor deposition flow;
Separately from the shutter, the collimator plate is disposed between the substrate to be processed and the vapor deposition raw material, and allows only the vapor deposition flow incident on the substrate to be processed at a constant small incident angle to pass through the vapor deposition flow. And depositing the vapor deposition flow on the substrate to be processed to form a film.   The vacuum deposition apparatus according to claim 1, further comprising a collimator plate height adjustment mechanism that can change a relative position of the collimator plate with respect to the substrate to be processed.   The vacuum deposition apparatus according to claim 1, further comprising a substrate holder rotating mechanism that rotates the substrate holder about an axis.   The vacuum deposition apparatus according to any one of claims 1 to 3, wherein the plurality of deposition boats are arranged uniformly in a diameter direction of the substrate to be processed.   The vacuum deposition apparatus according to any one of claims 1 to 3, wherein the plurality of deposition boats are uniformly arranged on a concentric circle with one at a center of the substrate to be processed.

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