JP2009088228A - Processing apparatus and processing method for substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a processing apparatus capable of partially cleaning a semiconductor wafer. <P>SOLUTION: The processing apparatus for partially cleaning the semiconductor wafer includes: a turntable 2 holding the semiconductor wafer; a nanobubble generator 17 which supplies processing liquid with mixed nanobubbles at least to a part to be cleaned of the semiconductor wafer held by the turntable; and an electron gun 12 which breaks nanobubbles contained in the processing liquid by irradiating the part to be cleaned of the semiconductor wafer with an electron beam. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a substrate processing apparatus and a processing method for partially cleaning a substrate such as a glass substrate used for a semiconductor wafer or a liquid crystal display panel.

  For example, when a circuit pattern is formed on a semiconductor wafer as a substrate, there is a step of forming a laminated film composed of a plurality of thin films such as a conductive film and an insulating film on the semiconductor wafer. Film formation on the semiconductor wafer is performed by, for example, a CVD apparatus. When a laminated film is formed on a semiconductor wafer, the laminated film may also be formed on the periphery of the semiconductor wafer.

  The semiconductor wafer on which the laminated film is formed is cleaned by a spin processing apparatus or the like. In that case, if the peripheral portion of the semiconductor wafer is clamped by the spin processing device, the laminated film on the peripheral portion may be peeled off, and the peeled laminated film adheres to the semiconductor wafer or other semiconductor wafers and causes contamination. Become.

  Therefore, conventionally, if a laminated film is formed on a semiconductor wafer, the peripheral part is etched over a range of 1 to 2 mm before passing to the next process, and the laminated film formed on the peripheral part is removed. It is done.

  When the laminated film is removed from the peripheral portion of the semiconductor wafer by etching, dirt such as an etching residue may remain attached to the peripheral portion. Therefore, it is required to clean the peripheral portion after the etching.

  When cleaning a semiconductor wafer, for example, as shown in Patent Document 1, the semiconductor wafer is accommodated in a processing tank to which a processing liquid is supplied. The treatment liquid contains microbubbles generated by a microbubble generator. An ultrasonic transducer is provided at the bottom of the treatment tank.

As a result, by applying ultrasonic vibration to the processing liquid supplied to the processing tank with an ultrasonic vibrator, the dirt adhering to the surface of the semiconductor wafer is peeled off by the impact of ultrasonic vibration and adsorbed by the microbubbles. Ascends with microbubbles. Accordingly, the dirt peeled off from the semiconductor wafer flows out from the upper end of the processing tank together with the microbubbles, so that the semiconductor wafer can be efficiently cleaned.
JP 2006-179765 A

  According to the processing apparatus disclosed in Patent Document 1, the cleaning effect on the semiconductor wafer is improved by using the impact of ultrasonic vibration on the semiconductor wafer. However, according to the processing apparatus having the above configuration, since the semiconductor wafer is immersed in the processing liquid in the processing tank, the entire surface of the semiconductor wafer is cleaned. It will be added to the entire surface of the wafer.

  For this reason, for example, even when it is desired to clean only the peripheral portion without impacting the device surface of the semiconductor wafer, the entire surface must be cleaned, so that the impact of ultrasonic vibration is applied to the entire surface. become. The circuit pattern formed on the device surface has recently been miniaturized. When the circuit pattern is miniaturized, if an impact of ultrasonic vibration is applied to the circuit pattern, the impact may cause damage.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a substrate processing apparatus and a processing method capable of reliably cleaning only a desired portion of a substrate.

The present invention is a processing apparatus for partially processing a substrate,
Holding means for holding the substrate;
A processing liquid supply means for supplying a processing liquid in which nanobubbles are mixed in at least a portion of the substrate held by the holding means;
An apparatus for processing a substrate, comprising: energy irradiation means for irradiating an energy beam onto a portion to be processed of the substrate to crush nanobubbles contained in the processing liquid.

The holding means is a rotary table that holds and rotates the substrate horizontally,
The treatment liquid supply means is a treatment tank in which the treatment liquid for storing the turntable and storing the substrate held on the turntable is stored.
The energy irradiating means is preferably constituted by an energy beam output unit that outputs an energy beam and a drive unit that drives the energy beam output unit along a predetermined direction above the rotary table.

The holding means is a rotary table that holds and rotates the substrate at a predetermined angle.
The treatment liquid supply means is a treatment tank to which a treatment liquid for immersing a portion located at the lower end of the peripheral portion of the substrate held at an inclination is supplied,
The energy irradiating means preferably includes an energy beam output unit that outputs an energy beam.

The present invention is a processing method for partially processing a substrate,
Holding the substrate;
Supplying a processing liquid in which nanobubbles are mixed in at least a portion to be processed of the held substrate;
And a step of irradiating an energy beam to a portion to be processed of the substrate to crush nanobubbles contained in the processing liquid.

  It is preferable that the substrate is rotated, a processing liquid is supplied to at least the periphery of the substrate, and the energy beam is irradiated to the periphery of the substrate.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 and 2 show an embodiment of the present invention. The processing apparatus shown in FIG. 1 includes a processing tank 1 whose upper surface is open. Inside the processing tank 1, a turntable 2 constituting a holding means is provided horizontally.

  A connecting shaft 3 is provided at the center of the lower surface of the rotary table 2. The connecting shaft 3 is rotatably inserted and supported by a liquid-tight bearing 4 provided at the center of the bottom of the processing tank 1 and protrudes from the outer bottom of the processing tank 1.

  A rotational drive source 6 is disposed below the processing tank 1. The drive shaft 7 of the rotational drive source 6 is connected to the connecting shaft 3. Thereby, the rotary table 2 is rotationally driven by the rotary drive source 6. The rotation speed of the rotary table 2 can be set by controlling the drive of the rotary drive source 6 by a control device (not shown).

  For example, a semiconductor wafer W as a substrate is detachably held on the turntable 2 by means such as suction. An energy irradiation means 11 is provided above the rotary table 2.

  The energy irradiation means 11 includes an electron gun 12 as an energy beam output unit that outputs an electron beam B that is an energy beam. This electron gun 12 is attached to a movable body 14 constituting a driving means 13. The movable body 14 is movably provided on a guide member 15 disposed horizontally along the radial direction of the semiconductor wafer W held on the turntable 2.

  A drive source 16 is provided at one end in the longitudinal direction of the guide member 15, and the drive source 16 can drive the movable body 14 in the X direction indicated by an arrow, which is a direction along the guide member 15. . That is, the electron gun 12 can be driven along the radial direction of the semiconductor wafer W held on the turntable 2.

  A treatment liquid L containing nanobubbles having a diameter of 1 μm or less is supplied to the treatment tank 1 from a nanobubble generator 17 as a treatment liquid supply means. That is, the nanobubble generator 17 is connected to a supply source 18 for supplying a treatment liquid L such as pure water and an supply source 19 for supplying a nitrogen gas or carbon dioxide gas.

The gas supplied to the nanobubble generator 17 becomes a swirl flow, and the treatment liquid L flows along the circumference of the gas as a swirl flow having a swirl speed higher than that of the gas. As a result, the gas is sheared by the processing liquid L to generate fine-sized bubbles, that is, nanobubbles, and the nanobubbles are mixed into the processing liquid L. That is, the treatment liquid L becomes nanobubble water.
Nanobubbles having a smaller diameter than microbubbles mixed in the treatment liquid L have small buoyancy. Therefore, the nanobubbles do not float on the upper surface of the processing liquid L, but stay in the processing liquid L and float.

  The particle size of the nanobubbles contained in the liquid can be set by the swirling speed of the gas and the liquid. In this embodiment, the nanobubbles having a diameter of 1 μm or less are generated by the gas sheared by the liquid. The swirling speed of the gas supplied to the generator 17 and the processing liquid L is set. Thereby, the treatment liquid L supplied to the nanobubble generator 17 becomes nanobubble water containing nanobubbles as described above.

  The treatment liquid L containing nanobubbles produced by the nanobubble generator 17 is supplied to the liquid storage tank 20. The liquid storage tank 20 and the bottom of the processing tank 1 are connected by a liquid supply pipe 21. A liquid supply pump 22 and a filter 23 are provided in the middle of the liquid supply pipe 21. Therefore, when the liquid supply pump 22 operates, the processing liquid L stored in the liquid storage tank 20 is supplied to the processing tank 1.

An overflow pipe 24 is connected to the processing tank 1. The overflow pipe 24 discharges the processing liquid L when the liquid level of the processing liquid L in the processing tank 1 exceeds a predetermined level. The liquid level of the processing liquid L in the processing tank 1 is set such that the upper surface of the semiconductor wafer W held on the upper surface of the turntable 2 is sufficiently immersed.
Note that the processing liquid flowing out from the overflow pipe 24 is discarded or reused.

Next, in the case where the semiconductor wafer W is partially cleaned by the processing apparatus having the above-described configuration, in this embodiment, referring to FIG. 2 for the case where the peripheral portion etched after film formation is cleaned as described above. While explaining.
First, the movable body 14 provided with the electron gun 12 is driven along the guide member 15, and the electron beam B output from the electron gun 12 is held on the rotary table 2 with the device surface facing upward. The electron gun 12 is positioned so as to irradiate the peripheral portion.

  Next, when the processing liquid L containing the nanobubbles 26 is supplied to the processing tank 1 and the semiconductor wafer W is immersed in the processing liquid L, the rotary table 2 is rotated and the electron beam B is emitted from the electron gun 12. Then, the peripheral edge of the semiconductor wafer W is irradiated.

  By rotating the turntable 2, when the peripheral portion of the semiconductor wafer W is irradiated with the electron beam B over the entire periphery, the processing liquid L positioned above the peripheral portion is also irradiated with the electron beam B. Become.

  As described above, the nanobubbles 26 do not float on the liquid surface of the processing liquid L, but float in the processing liquid L. Therefore, since the electron beam B emitted from the electron gun 12 irradiates the nanobubbles 26 floating on the upper surface of the peripheral edge of the semiconductor wafer W, the nanobubbles 26 are crushed by the energy of the electron beam B.

  When the nanobubbles 26 are crushed, an impact due to the crushing, that is, an impact force is generated, and the impact force acts on the upper surface of the peripheral portion of the semiconductor wafer W. The dirty dirt will be removed.

  That is, only the entire length of the peripheral portion of the semiconductor wafer W is cleaned, and the portions other than the peripheral portion of the device surface are not processed. In other words, since the semiconductor wafer W is not subjected to an impact other than the peripheral portion, only the peripheral portion can be reliably cleaned without causing damage to the circuit pattern formed on the device surface.

  The electron gun 12 can be driven along the radial direction of the semiconductor wafer W held on the turntable 2 by the driving means 13. Therefore, the cleaning process of the semiconductor wafer W is not limited to the peripheral edge portion, and can be partially performed even in the middle portion in the radial direction, and is performed by rotating the turntable 2 over the entire circumferential direction. If the turntable 2 is stopped, only a part in the circumferential direction can be cleaned.

  FIG. 3 shows another embodiment of the present invention. In this embodiment, the rotary table 2 is arranged with the rotation axis inclined at a predetermined angle. The peripheral portion of the semiconductor wafer W protrudes outward from the outer periphery of the turntable 2, and the peripheral portion located at the lower end in the tilt direction of the semiconductor wafer W is immersed in the processing liquid L containing nanobubbles supplied to the processing tank 1A. Has been. That is, only a part of the peripheral edge of the semiconductor wafer W is immersed in the processing liquid L.

  An electron beam B output from the electron gun 12 is irradiated on the peripheral edge of the semiconductor wafer W immersed in the processing liquid L from a direction perpendicular to the device surface of the semiconductor wafer W. Accordingly, only the peripheral edge portion of the semiconductor wafer W can be immersed in the processing liquid L and cleaned. In other words, only the portion to be cleaned is immersed in the processing liquid L, and the portion that does not need to be cleaned does not need to be immersed in the processing liquid L.

  In each of the above embodiments, nanobubbles are mixed in pure water as a processing liquid, but the liquid used as the processing liquid is not limited to pure water, and a liquid having a high cleaning effect according to the type of contamination of the semiconductor wafer, for example, Other liquids such as isopropyl alcohol may be used. Similarly, the type of gas for generating nanobubbles is not limited.

Moreover, although the semiconductor wafer was mentioned as an example as a board | substrate, the rectangular glass substrate used for a liquid crystal display panel may be sufficient.
Also, an electron beam output from an electron gun as an energy beam has been taken as an example, but as an energy beam, a laser beam output from a laser oscillator, an ultrasonic vibration output from an ultrasonic transducer, an ion beam, or An ultraviolet beam or the like may be used. In short, any material may be used as long as it can apply energy to the nanobubbles existing in the processing liquid and crush the nanobubbles.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram of the processing apparatus which shows one embodiment of this invention. The enlarged view of the edge part to which the electron beam of a semiconductor wafer is irradiated. The enlarged view of the edge part to which the electron beam of the semiconductor wafer which shows other embodiment of this invention is irradiated.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Processing tank, 2 ... Rotary table (holding means), 11 ... Energy irradiation means, 12 ... Electron gun (energy beam output part), 17 ... Nano bubble generator (processing liquid supply means).

Claims (5)

A processing apparatus for partially cleaning a substrate,
Holding means for holding the substrate;
A treatment liquid supply means for supplying a treatment liquid in which nanobubbles are mixed in at least a portion to be cleaned of the substrate held by the holding means;
An apparatus for processing a substrate, comprising: energy irradiation means for irradiating an energy beam onto a portion of the substrate to be cleaned to crush nanobubbles contained in the processing liquid. The holding means is a rotary table that holds and rotates the substrate horizontally,
The treatment liquid supply means is a treatment tank in which the treatment liquid for storing the turntable and storing the substrate held on the turntable is stored.
The energy irradiating means includes an energy beam output unit that outputs an energy beam, and a driving unit that drives the energy beam output unit along a predetermined direction above the rotary table. Item 2. A substrate processing apparatus according to Item 1. The holding means is a rotary table that holds and rotates the substrate at a predetermined angle.
The treatment liquid supply means is a treatment tank to which a treatment liquid for immersing a portion located at the lower end of the peripheral portion of the substrate held at an inclination is supplied,
The substrate processing apparatus according to claim 1, wherein the energy irradiation unit includes an energy beam output unit that outputs an energy beam toward a peripheral portion of the substrate immersed in the processing solution. A processing method for partially cleaning a substrate,
Holding the substrate;
Supplying a treatment liquid in which nanobubbles are mixed in at least a portion of the substrate to be cleaned;
And a step of irradiating an energy beam onto a portion to be processed of the substrate to crush the nanobubbles contained in the processing liquid.   5. The substrate processing method according to claim 4, wherein the substrate is rotated, a processing liquid is supplied to at least a peripheral portion of the substrate, and an energy beam is irradiated to the peripheral portion of the substrate.

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