JP2009135522A - Substrate processing apparatus and method for manufacturing ic - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact substrate processing apparatus with excellent space efficiency. <P>SOLUTION: There is provided a substrate processing apparatus including a sputtering chamber 12 for applying sputtering to a wafer; a wafer chuck 20 for holding a wafer 1 stored in the sputtering chamber 12; a rotation mechanism 21 for rotating the wafer chuck 20 holding the wafer 1; and a milling ion source 30 for emitting ion beam 36 toward the wafer 1, wherein the short side of a milling electrode 32 of the milling ion source 30 is formed into a rectangular shape with a short side smaller than the outer diameter of the wafer, and an aperture ratio of an opening part 33 of the milling electrode 32 is set to be greater on the peripheral side than on the center side of the wafer. When the wafer is irradiated with the ion beam, while rotating the wafer in milling, milling processing amount is made uniform on an entire surface of the wafer. A size of the milling ion source is made small, and therefore miniaturization of the sputtering device is realized by improving space efficiency. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a substrate processing apparatus, for example, a semiconductor integrated circuit device (hereinafter referred to as an IC).
In this manufacturing method, the semiconductor wafer (hereinafter referred to as a wafer) on which an IC is fabricated is effectively used for forming a metal film on one main surface of the semiconductor wafer by sputtering.

In an IC manufacturing method, a thin film forming method using a sputtering apparatus is widely used as a thin film forming method for forming a metal film on one main surface of a wafer.
In general, a sputtering apparatus includes a pair of electrodes disposed in a sputtering chamber, and one of the electrodes is mounted with a target formed using the same material as the metal film to be deposited on the wafer. And the other electrode is configured to hold the wafer. For example, see Patent Document 1.

JP 2005-93789 A

For example, when pre-cleaning is performed by irradiating a wafer with an ion beam before sputtering, in order to irradiate the wafer with a uniform ion beam, the ion beam needs to be irradiated over a wider area than the wafer. As the wafer becomes larger, there is a problem that the ion supply section becomes larger and the entire apparatus becomes larger.

An object of the present invention is to provide a compact substrate processing apparatus with good space efficiency.

Representative inventions disclosed in the present application are as follows.
(1) a processing chamber for processing a substrate;
A substrate holder stored in the processing chamber and holding the substrate;
A rotating mechanism that is housed in the processing chamber and rotates while holding the substrate in the substrate holder;
An ion supply unit that is adjacent to the processing chamber and irradiates the processing chamber with an ion beam;
The ion supply unit is configured such that when the substrate held by the substrate holder is arranged to face the ion supply unit, the short side of the ion supply unit is smaller than the outer diameter of the substrate, and the ion supply unit A substrate processing apparatus, wherein a long side of the supply unit is formed in a rectangular shape larger than the outer diameter of the substrate.
(2) a processing chamber for processing a substrate;
A substrate holder stored in the processing chamber and holding the substrate;
A rotating mechanism that is housed in the processing chamber and rotates while holding the substrate in the substrate holder;
An ion supply unit that is adjacent to the processing chamber and irradiates the processing chamber with an ion beam;
The ion supply unit includes an electrode having an opening for extracting an ion beam into the processing chamber,
When the electrode is disposed so that the substrate held by the substrate holder faces the electrode, the short side of the electrode has a rectangular shape smaller than the outer diameter of the substrate, and the opening The substrate processing apparatus, wherein an aperture ratio is set so that the substrate end side is larger than the center side of the substrate.
(3) a processing chamber for processing a substrate;
A substrate holder stored in the processing chamber and holding the substrate;
A rotating mechanism that is housed in the processing chamber and rotates while holding the substrate in the substrate holder;
An ion supply unit that irradiates an ion beam from an opening provided in an electrode in the processing chamber adjacent to the processing chamber;
When the electrode is arranged so that the substrate held by the substrate holder faces the electrode, the short side of the electrode is smaller than the outer diameter of the substrate, and the long side of the electrode is the substrate A substrate processing apparatus, wherein the substrate processing apparatus is formed in a rectangular shape larger than the outer diameter.
(4) a processing chamber for processing the substrate;
A substrate holder stored in the processing chamber and holding the substrate;
A rotating mechanism that is housed in the processing chamber and rotates while holding the substrate in the substrate holder;
An ion supply unit that is adjacent to the processing chamber and irradiates the processing chamber with an ion beam;
The ion supply unit is arranged such that the ion beam irradiated from the ion supply unit is rotated while the substrate is rotated once while the substrate held by the substrate holder is arranged to face the ion supply unit. A substrate processing apparatus, wherein the irradiation amount is substantially the same at the center of the substrate surface of the ion supply unit and at the substrate end.

According to the above-described means, since the space efficiency can be improved by setting the ion supply portion compact, the entire apparatus can be designed compactly.

It is a front view which shows the sputtering device of the substrate processing apparatus which is one embodiment of this invention. FIG. It is side surface sectional drawing which shows the time of milling. (A) is a perspective view which shows the relationship between the electrode for milling, and a wafer, (b) is a schematic diagram which shows the irradiation range of a comparative example, (c) is a schematic diagram which shows the irradiation range of this Embodiment. It is side surface sectional drawing which shows the time of sputtering.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

In the present embodiment, the substrate processing apparatus according to the present invention includes the sputtering apparatus 10 shown in FIGS. 1 and 2.

The sputtering apparatus 10 includes a vacuum container 11 formed in a rectangular parallelepiped housing shape.
The vacuum vessel 11 constitutes a sputtering chamber 12 as a processing chamber, and the sputtering chamber 12 is evacuated by a vacuum pump (not shown).
Loading / unloading port 13 for loading / unloading wafer 1 as a substrate into / from sputtering chamber 12.
And the carry-in / out port 13 is configured to be opened and closed by a gate valve 14.
Further, the sputtering chamber 12 is provided with a gas supply pipe (not shown) for supplying argon gas as a discharge gas having an inert and large mass for generating ions.

A target 15 is disposed at an upper portion of the sputtering chamber 12 with an inclination angle of, for example, 45 degrees, and the posture of the target 15 is configured to be controlled by a posture control device (not shown). It should be noted that the tilt angle is controlled to be different depending on the material of the target 15.
As will be described later, the target 15 is sputtered by argon ions to eject the composition and form a sputtering film on the wafer 1, and is formed into a disk shape from a desired metal. The target 15 is not only disk-shaped but may be square-shaped.

A sputtering ion source 16 is horizontally installed on one of the pair of side walls (hereinafter referred to as the left side wall) of the vacuum vessel 11 where a horizontal line passing through the center of the target 15 intersects. The sputtering ion source 16 is called a bucket ion source, and includes an ion generation unit that generates argon ions and an extraction electrode that irradiates the target 15 with the argon ions generated by the ion generation unit as an ion beam. ing.

A wafer chuck 20 as a substrate holder is disposed on a vertical line passing through the center of the target 15 in the sputtering chamber 12. The wafer chuck 20 is configured to be rotated by a rotation mechanism 21, and a tilt mechanism. (Not shown) is configured such that the posture is changed (tilted) between a horizontal posture (a posture where the holding surface is horizontal) and a vertical posture (a posture where the holding surface is vertical).

A milling ion source 30 for irradiating ions is horizontally installed on the right side wall of the vacuum vessel 11 where a horizontal line passing through the center of the wafer chuck 20 in the vertical posture (see FIG. 3) intersects.
As shown in FIG. 3, the milling ion source 30 is a so-called bucket ion source, and includes an ion generation unit 31 that generates argon ions as an ion supply unit therein,
An extraction electrode (hereinafter, referred to as a milling electrode) 32 that extracts argon ions generated by the ion generation unit 31 toward the wafer 1 on the wafer chuck 20 as an ion beam is provided.
As shown in FIG. 4A, the milling electrode 32 includes an opening 33 through which an ion beam is transmitted, and the opening ratio of the opening 33 is the wafer 1 held by the wafer chuck 20.
Is set so that the end side of the wafer 1 is larger than the center side of the wafer 1 when the is placed in a vertical posture facing the milling ion source 30.
That is, the milling electrode 32 is formed in a rectangular shape whose vertical direction is shorter than the outer diameter of the wafer 1 and whose horizontal direction is longer than the outer diameter of the wafer 1. , 34 and a pair of opening areas 35, 35 are formed on the left and right, respectively, and an opening is formed by the pair of opening areas 35, 35 on the left and right.
As shown in FIG. 4 (c), both blank areas 34, 34 are milling electrodes 3
2 and four intersections a, b, c, d between the upper and lower long sides and the circumference of the wafer 1 when arranged in a vertical posture facing the milling ion source 30, and b, They are respectively set as a pair of isosceles triangle areas on the upper and lower sides so that the diagonal line connecting d is substantially the same as the area defined by the diagonal line.
The left and right opening areas 35, 35 are respectively set as a pair of elongated pentagonal (house-shaped) areas excluding the upper and lower blank areas 34, 34 in the rectangular milling electrode 32. 35 has a plurality of circular (preferably substantially circular) openings (hereinafter referred to as small holes) 33a formed in a matrix (lattice) shape.

Next, the operation will be described.
A wafer 1 to be sputtered is loaded into a sputtering chamber 12 previously depressurized to a predetermined pressure from a loading / unloading port 13 and transferred onto a wafer chuck 20 in a horizontal position indicated by a broken line in FIG.

Next, as shown in FIG. 3, the wafer chuck 20 is tilted to a vertical posture by a tilt mechanism.
Subsequently, while the wafer chuck 20 is rotated by the rotating mechanism 21, the ion beam 36 is irradiated onto the wafer 1 from the ion source 30 for milling, and the wafer 1 is subjected to ion milling. As a result, the oxide film on the wafer 1 is removed.
Here, the ion milling process refers to a processing method for cutting an object by irradiating the object (wafer) with an ion beam.
At this time, as shown in FIG. 4A, the opening ratio of the opening 33 of the rectangular milling electrode 32 is set so that the peripheral side of the wafer 1 is larger than the center side of the wafer 1, and the wafer Since 1 is rotated, the irradiation amount of the ion beam 36 to the wafer 1 is substantially the same at the center and the peripheral portion of the irradiation surface of the wafer 1.
Therefore, the milling amount of the wafer 1 by the ion beam 36 of the milling ion source 30 is uniformly distributed over the entire surface of the wafer 1.

By the way, as shown in FIG. 4B, the milling electrode is formed in a disk shape having a diameter larger than that of the wafer 1, and the opening ratio of the opening is set in the disk-shaped milling electrode 32 ′. In the case where the entire surface is uniformly set, the range other than the wafer 1 to which the ion beam is irradiated is an all-round irradiation range 37 ′ outside the circumference of the wafer 1 as indicated by the hatched area.
On the other hand, in the present embodiment, the range other than the wafer 1 irradiated with the ion beam 36 is outside the circumference of the wafer 1 as shown by the hatched range in FIG. There are only narrow irradiation ranges 37 and 37 corresponding to both opening areas 35 and 35 in the rectangular milling electrode 32, respectively.
Therefore, according to the present embodiment, the phenomenon in which particles are generated by irradiating an area other than the wafer 1 in the sputtering chamber 12 with the excess ion beam 36 is compared with the case of the disk-shaped milling electrode 32 ′. Can be suppressed.

Thereafter, as shown in FIG. 5, the wafer chuck 20 is tilted to a horizontal posture by a tilt mechanism.
Subsequently, the ion beam 17 of argon ions is irradiated from the ion source 16 for sputtering to the target 15 while the wafer chuck 20 is rotated by the rotating mechanism 21. When the target 15 is irradiated with the ion beam 17, the sputtered particles 18 from the target 15.
Jumps out.
The sputtered particles 18 that jump out are deposited on the surface of the wafer 1, and the surface of the wafer 1 is coated with the sputtered particles 18.

When a sputtering film having a desired thickness is formed on the wafer 1 as described above, the above-described sputtering operation is stopped, and the carry-in / out port 13 is opened by the gate valve 14 and held by the wafer chuck 20. The processed wafer 1 is unloaded from the loading / unloading port 13.

  According to the embodiment, the following effects can be obtained.

1) The size of the milling ion source can be reduced by forming the milling electrode into a rectangular shape whose shorter side is smaller than the outer diameter of the wafer and whose longer side is larger than the outer diameter of the wafer. By improving, for example, sputtering which is the main treatment can be performed immediately after removing the oxide film in the same sputtering chamber.

2) By forming the milling electrode in a rectangular shape whose shorter side is smaller than the outer diameter of the wafer and whose longer side is larger than the outer diameter of the wafer, the area other than the wafer irradiated with the ion beam can be Since it can be limited to a narrow range outside the circumference of the wafer, it is possible to suppress a phenomenon in which particles are generated by irradiating a region other than the wafer in the sputtering chamber with an extra ion beam.

3) By setting the aperture ratio of the opening of the rectangular milling electrode so that the peripheral side is larger than the center side of the wafer, and rotating the wafer, the irradiation amount of the ion beam to the wafer can be set on the irradiation surface of the wafer. Since the center portion and the peripheral portion can be set to substantially the same amount, the milling amount of the wafer by the ion beam of the milling ion source can be made uniform over the entire surface of the wafer.

Needless to say, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.

For example, in the configuration in which the opening ratio of the opening portion of the rectangular milling electrode is set to be larger on the peripheral side than the center side of the wafer, a plurality of small holes constituting the opening portion are uniformly formed in a pair of elongated pentagonal areas. However, the pitch of the adjacent small holes in the opening is changed between the central portion and the peripheral portion (the pitch of the peripheral portion is made wider toward the outside than the pitch of the central portion).
The diameter of the small hole in the opening may be changed between the central part and the peripheral part (the diameter of the small hole in the peripheral part is made larger toward the outside than the diameter of the small hole in the central part) .) Configuration may also be used.
In short, the ion source for milling is such that the ion beam irradiated from the milling ion source during one rotation of the wafer has substantially the same dose at the central portion of the irradiation surface of the wafer and the peripheral portion of the irradiation surface. What is necessary is just to comprise.

Although the sputtering apparatus has been described in the above embodiment, the present invention is not limited to this and can be applied to all substrate processing apparatuses.

The substrate is not limited to a wafer, and may be a printed wiring board, a liquid crystal panel, a magnetic disk, a compact disk, or the like.

DESCRIPTION OF SYMBOLS 1 ... Wafer (substrate), 10 ... Sputtering apparatus, 11 ... Vacuum container, 12 ... Sputtering chamber (processing chamber), 13 ... Loading / unloading port, 14 ... Gate valve, 15 ... Target, 16 ...
Ion source for sputtering, 17 ... ion beam, 18 ... sputtered particles, 20 ... wafer chuck (substrate holder), 21 ... rotating mechanism, 30 ... ion source for milling (ion supply unit),
31 ... Ion generating part, 32, 32 '... Milling electrode (extraction electrode), 33 ... Opening part, 33
a ... small hole (opening), 34 ... blank area, 35 ... opening area, 36 ... ion beam,
37, 37 '... irradiation range.

Claims (2)

A processing chamber for processing the substrate;
A substrate holder stored in the processing chamber and holding the substrate;
A rotation mechanism that is housed in the processing chamber and rotates while holding the substrate in the substrate holder; and an ion supply unit that irradiates an ion beam into the processing chamber adjacent to the processing chamber;
The ion supply unit includes an electrode having an opening for extracting an ion beam into the processing chamber,
When the electrode is disposed so that the substrate held by the substrate holder faces the electrode, the short side of the electrode has a rectangular shape smaller than the outer diameter of the substrate, and the opening The substrate processing apparatus, wherein an aperture ratio is set so that the substrate end side is larger than the center side of the substrate. While rotating the substrate held by the substrate holder in the processing chamber,
An electrode having an opening of an ion beam supply unit disposed at a position facing the substrate,
The substrate is irradiated with an ion beam from the opening of the electrode, the short side of which is formed in a rectangular shape smaller than the outer diameter of the substrate, and the opening ratio of the opening is set to be larger on the substrate end side than the center side of the substrate IC manufacturing method comprising the steps of: