JP6197641B2 - Vacuum ultraviolet irradiation treatment equipment - Google Patents

Description

  The present invention relates to a vacuum ultraviolet light irradiation processing apparatus equipped with a light source that emits vacuum ultraviolet light.

  With the miniaturization and high integration of semiconductor integrated circuits, the wavelength of exposure light sources has been shortened. Currently, an ArF excimer laser device that emits vacuum ultraviolet (hereinafter also referred to as VUV) light having a wavelength of 193 nm is used as a light source for exposure. An exposure apparatus equipped with an ArF excimer laser apparatus employs a projection exposure system that performs reduced projection exposure using laser light as parallel light.

In recent years, VUV light having a wavelength of 200 nm or less has been used in various fields other than semiconductor exposure. For example, a technique for patterning a self-assembled monomolecular film (hereinafter referred to as a SAM film) by causing a chemical reaction with direct light using a VUV and a mask without using a pattern formation process using a photoresist has been developed. Non-Patent Document 1 discloses that photopatterning of a SAM film that does not depend on a specific functional group is possible using VUV. Specifically, an excimer lamp having a wavelength of 172 nm, which is used to remove contaminants made of organic substances, is used as an exposure light source. This method focuses on the oxidative decomposition removal reaction of the SAM film by VUV, and can be expected to be applied to optical micromachining of various SAM films.
On the other hand, it is known that high-speed surface modification (for example, ashing) or the like can be realized particularly for light in a wavelength region having a wavelength of 180 nm or less in VUV.

As a vacuum ultraviolet light source (hereinafter also referred to as a VUV light source), a low-pressure mercury lamp having an emission line at a wavelength of 185 nm has been conventionally used. In recent years, as described above, in many cases, a xenon excimer lamp that emits light having a wavelength of 172 nm is used as a VUV light source.
The above-described lamp that emits VUV generally has a long light emitting portion, that is, a long light emission length. For example, a low-pressure mercury lamp (UL0-6DQ manufactured by USHIO INC.) Has a light emission length of 10 cm. For example, an excimer light unit (SUS06 manufactured by USHIO INC.) Having a built-in xenon excimer lamp has a light emission length of 10 cm.

  In general, a VUV lamp mounted on a VUV light source device that emits VUV light has a relatively long light emission length. Further, the VUV light emitted from such a VUV lamp becomes divergent light. In the case of diverging light, it is difficult to perform projection exposure, and contact exposure and proximity exposure are performed. In this case, the exposure to the irradiated object is limited by the influence of diverging light, and the resolvable pattern size is limited to about 100 μm as the line pattern width.

  Also in the patterning of the SAM film described above, there is a demand for fine pattern line width. In order to meet the demand for miniaturization, it is conceivable to use an excimer laser exposure apparatus used for semiconductor exposure. However, excimer laser devices and excimer laser exposure devices are expensive, and are not practical from the viewpoint of COO (cost of ownership) to be used for other than semiconductor exposure that is already in mass production. In other words, the excimer laser device is limited to use in an industrial field commensurate with the COO.

As an exposure light source of the previous generation of the excimer laser exposure apparatus, an ultraviolet lamp as a point light source has been used.
In order to obtain parallel light or substantially parallel light necessary for fine patterning, for example, as in Patent Document 1, an ultraviolet irradiation device using a point light source (lamp), a condenser mirror, and a collimator lens is used. It was used. If the VUV lamp that emits VUV is a point light source, a light irradiation device that extracts VUV light, which is parallel light or substantially parallel light, can be realized by being incorporated in the above-described ultraviolet irradiation device. Patterning with a pattern size of several μm or less can be realized by constructing an illumination optical system using the above-described parallel light or substantially parallel light and performing exposure with less light wraparound. Such a light source device is cheaper than an excimer laser device and is a practical light source device from the viewpoint of COO.

  The inventors previously described a VUV flash lamp (hereinafter also referred to as a VUV short arc flash lamp: VUV-SFL) having a light emission length of 12.5 mm or less and a strong light intensity in the VUV region, and a power supply device for the lamp. A light source device including By incorporating this light source device into a conventional ultraviolet irradiation device, it has become possible to realize a light irradiation device that extracts VUV light that is parallel light or substantially parallel light.

FIG. 6 shows a structural example in which VUV-SFL is incorporated in a conventional ultraviolet irradiation processing apparatus.
A flash lamp 1 and a parabolic mirror 2 are arranged in the lamp housing 3. A power supply unit 13 including a capacitor, a step-up transformer, and a trigger circuit unit that generates a start trigger pulse via a power supply line for supplying power and a start trigger pulse to the flash lamp 1 (not shown) 12 and a power supply means including a charger for charging the capacitor of the power supply unit 13. In FIG. 6, the charger is omitted.

  The flash lamp 1 is arranged so that the position of the light emitting part (short arc generating part between the electrodes) substantially coincides with the position of the focal point of the parabolic mirror 2. The light emitted from the flash lamp 1 is collimated by the parabolic mirror 2 and then emitted from the quartz window 4 to the outside of the lamp housing 3. The light transmissive window that transmits the light emitted from the flash lamp 1 is configured as, for example, a quartz window 4 made of synthetic quartz having high transmittance for VUV light. If necessary, sapphire glass, calcium fluoride, or magnesium fluoride having a shorter wavelength than quartz can be used as the material of the light transmissive window.

The quartz window 4 is assembled airtight with the lamp housing 3, and the inside of the lamp housing 3 is purged by introducing an inert gas such as N ₂ gas from a first gas inlet 3 a provided in the lamp housing 3. . In the case of a conventional ultraviolet irradiation device, air is used as a purge gas for cooling the lamp and the like in the lamp housing 3. However, in the case of VUV, the VUV intensity is significantly attenuated due to absorption by oxygen in the air.
Moreover, ozone is generated in the VUV optical path by absorbing the VUV light by oxygen in the atmosphere. Ozone is a highly reactive gas and damages components (for example, power supply means) in the lamp housing 3. For example, ozone causes oxidative degradation of electronic components such as a power supply line (wiring member), a trigger substrate, and a capacitor.
Further, when the purge gas is exhausted to the outside of the lamp housing 3, since ozone is contained in the purge gas, it is necessary to provide an ozone filter.

Therefore, it is possible to prevent absorption attenuation due to oxygen of VUV by purging the inside of the lamp housing with an inert gas such as N ₂ gas. Further, the generation of ozone is suppressed, the components in the lamp housing 3 are not damaged, and it is not necessary to provide an ozone filter when discharging the purge gas outside the lamp housing 3.
An inert gas such as N ₂ gas introduced into the lamp housing 3 cools the power supply means (power supply unit, trigger circuit unit), the flash lamp 1 and the parabolic mirror 2 and then is provided in the lamp housing 3. Is exhausted from the exhaust port 3b.

  Aluminum is deposited on the inner surface (light reflecting surface) of the parabolic mirror 2 to form an aluminum reflecting film. Aluminum is suitable as a mirror material because it has a characteristic of efficiently reflecting VUV.

  A processing chamber 5 that holds a workpiece W irradiated with VUV light is provided below the quartz window 4 from which VUV light is extracted from the lamp housing 3. In the processing chamber 5, a work stage 7 that holds the work W is provided on the bottom surface thereof. Further, as described above, the SAM film is applied to the work surface, and when the SAM film is patterned, the mask 6 is provided with a transfer pattern to the work surface between the work W and the quartz window portion 4. Is provided.

As described above, since the VUV light is absorbed by oxygen in the air and the intensity is attenuated, the space between the quartz window portion 4 and the mask 6 needs to be purged with an inert gas such as N ₂ gas. On the other hand, the patterning process of the workpiece W having a patterning process layer such as a SAM film on the surface is performed by irradiating the VUV light transmitted through the mask 6, but depending on the patterning process layer, the process layer The presence of oxygen near the surface can increase the patterning rate.
In other words, the space between the mask 6 and the workpiece W is not necessarily an inert gas atmosphere such as N ₂ gas, and the VUV on the surface is appropriately selected according to the material of the patterning layer on the workpiece. By making the atmosphere containing oxygen to such an extent that the light intensity does not decrease significantly, an active oxygen having an appropriate concentration is generated on the processing surface of the workpiece, and VUV effectively acts on the processing surface of the workpiece.

Therefore, the inside of the processing chamber 5 for processing the workpiece W is masked by the mask 6 with the mask upper space A that is a space between the quartz window 4 and the mask 6 and the workpiece processing space B in which the workpiece on the lower surface of the mask 6 is installed. And divided. The mask upper space A and the work processing space B are purged so as to have different atmospheres.
In FIG. 6, the mask upper space A is introduced from the third gas introduction port 5d and purged with an inert gas such as N ₂ gas exhausted from the second exhaust port 5a. In this example, the gas is purged with a mixed gas composed of nitrogen and oxygen introduced from the gas inlet 5b and exhausted from the third exhaust 5c.

JP-A-6-97048

Hiroyuki Sugimura “Optical Microfabrication of Organic Monolayers”, Vacuum, Japan Vacuum Boundary, Vol. 48. No. 9 pp. 506-510 (2005)

As described above, when a VUV short arc flash lamp (VUV-SFL) is incorporated in a conventional ultraviolet irradiation processing apparatus, the VUV light is absorbed by oxygen in the air and the intensity of the VUV light is attenuated or ozone is generated. In order to prevent a problem that the components in the lamp housing are damaged by the leverage of the lever, it is necessary to purge the inside of the lamp housing 3 with an inert gas such as N ₂ gas, and the VUV light in the processing chamber 5 When the workpiece patterning process is performed, the processing chamber is divided into two parts by the mask 6 on which the exposure pattern is applied, and the space between the quartz window part 4 serving as the VUV light extraction part of the lamp housing 3 and the upper surface of the mask 6 is divided. be purged with an inert gas such as N ₂ gas to mask the upper space a also to prevent decay by oxygen VUV a space There is a need. In the processing chamber 5, the work processing space B in which the work W on the lower surface of the mask 6 is installed is purged with, for example, a mixed gas composed of nitrogen and oxygen so as to have an atmosphere suitable for the patterning process.

That is, in the ultraviolet irradiation processing apparatus using VUV-SFL, it is necessary to individually purge the inside of the lamp housing 3, the mask upper space A, and the work processing space B, and the configuration becomes complicated.
Further, the lamp housing 3 is relatively large because there are many components including the power feeding means, the parabolic mirror 2 and the VUV-SFL 1. When purging oxygen from within this space, it takes time until oxygen is purged from the inside of the lamp housing by flowing an inert gas such as N ₂ gas into the lamp housing. Naturally, in order to prevent air containing oxygen from flowing into the lamp housing from the outside space, the lamp housing needs a large-scale sealing structure.
Furthermore, the VUV light has a large energy because of its short wavelength, and if an undesired portion in the ultraviolet irradiation processing apparatus is irradiated with the VUV light, the irradiated portion may be deteriorated.

Therefore, an inexpensive vacuum ultraviolet light irradiation processing apparatus that can solve the above-described problems and can irradiate parallel VUV light without using an expensive apparatus such as an excimer laser is desired.
The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a vacuum ultraviolet light irradiation processing apparatus that can irradiate a workpiece without attenuating VUV light, has a simple structure, and is practical. There is.

In order to solve the above-described problems, in the present invention, a work chamber to which a vacuum ultraviolet light is irradiated and a processing chamber holding a mask are hermetically divided into two spaces by the mask. In other words, the mask upper space A, which is a space between the quartz window portion for emitting vacuum ultraviolet light provided in the lamp housing, and the mask, and the work processing space B, which is a space where the work is placed on the lower surface of the mask, are airtight. To divide. And the passage hole which connects the inside of a lamp housing and the said mask upper space A spatially is provided.
The inert gas introduced into the lamp housing and cooling the flash lamp and the parabolic mirror is exhausted from the first exhaust port provided in the lamp housing, and part of the inert gas passes through the passage hole and passes through the processing chamber. Is introduced into the mask upper space A, and the air is purged therefrom and exhausted from a second exhaust port provided in the mask upper space A.
In addition, a gas containing oxygen is introduced into the work processing space B from the second gas introduction port, the work processing space B is purged by the gas, and exhausted from the third gas exhaust port.
By adopting such a configuration, it is possible to simultaneously perform the inert gas purge to the lamp housing 3 and the mask upper space A by using a common one-system gas supply / exhaust system, thereby simplifying the configuration of the apparatus. be able to.
In addition, a purge box containing at least a part of the parabolic mirror, the light emitting part of the short arc flash lamp, the opening of the passage hole, the quartz window part, etc. is provided in the lamp housing, and the inertness is contained in the purge box. A gas may be supplied, and an inert gas may be supplied from the purge box to the space in the lamp housing, and may be supplied to the mask upper space A through the passage hole.
With this configuration, oxygen can be purged with an inert gas in a short time from the purge box including the optical path of vacuum ultraviolet light.
Further, after introducing an inert gas into the purge box and purging the interior, the inert gas is supplied from the purge box to the space inside the lamp housing, so oxygen present in the space outside the purge box is removed. The contained gas (air) does not enter the inside of the purge box, and the sealing structure of the relatively large lamp housing can be simplified as long as the inside of the purge box is secured. .
Further, by arranging a light shielding plate that shields light emitted from the short flash lamp above the passage hole via an opening surface of the passage hole and a gap, VUV to an undesired place in the processing chamber is provided. Irradiation of light is prevented, and deterioration of the irradiated portion caused by irradiation with vacuum ultraviolet light is suppressed.

Based on the above, in the present invention, the above-described problem is solved as follows.
(1) A short arc flash lamp that emits light including at least vacuum ultraviolet light and a parabolic mirror that emits the light emitted from the short flash lamp as parallel light in one direction are disposed inside, A lamp housing having a gas inlet to which an inert gas is supplied; a light transmissive window provided in the lamp housing for transmitting parallel light emitted from the parabolic mirror; and the light transmissive window. Vacuum ultraviolet light irradiation processing apparatus comprising a mask irradiated with parallel light that has passed, a workpiece irradiated with the parallel light through the mask, and a processing chamber in which a work stage holding the workpiece is disposed. And the inside of the processing chamber is surrounded by a mask surrounded by a surface including the upper surface of the mask and the light exit surface of the light transmissive window. In a vacuum ultraviolet light irradiation processing apparatus in which a work processing gas is supplied to the work processing space, which is hermetically divided into a space and a work processing space on the lower surface side of the mask where the work and the work stage are arranged. One or more passage holes for spatially connecting the inside and the mask upper space are provided, and the inert gas supplied into the lamp housing is exhausted to the outside after passing through the passage hole in the mask upper space. A gas exhaust port is provided.
(2) A short arc flash lamp that emits light including vacuum ultraviolet light, a parabolic mirror that emits light emitted from the short flash lamp as parallel light in one direction, and a starting light for the short flash lamp. A lamp housing in which a power supply device for supplying a trigger pulse and electric power is disposed, a light-transmitting window portion that is provided in the lamp housing and transmits parallel light emitted from the parabolic mirror, and the light transmission A vacuum ultraviolet ray comprising: a mask irradiated with parallel light that has passed through a conductive window; a work irradiated with the parallel light through the mask; and a processing chamber in which a work stage holding the work is disposed. A light irradiation processing apparatus, wherein the inside of the processing chamber is a mask and includes a top surface of the mask and a light emitting surface of the light transmissive window The mask upper space surrounded by the mask and the work processing space on the lower surface side of the mask where the work and the work stage are arranged are hermetically divided, and the work processing space is supplied with a vacuum ultraviolet to which a work processing gas is supplied. In the light irradiation processing apparatus, at least one passage hole for spatially connecting the inside of the lamp housing and the mask upper space is provided. The lamp housing includes at least a part of the parabolic mirror, the light emitting portion of the short arc flash lamp, the opening of the passage hole, and a quartz window, and a communication hole between the lamp housing and the lamp housing. A purge box is provided. The purge box has a gas introduction port through which an inert gas is supplied inserted through the lamp housing, and the inert gas is supplied into the purge box from the gas introduction port. The inert gas supplied into the purge box by the opening is supplied to the space outside the purge box in the lamp housing through the communication hole and to the space above the mask through the passage hole. The inert gas supplied into the lamp housing passes through the passage hole, and is then exhausted to the outside from a gas exhaust port provided in the mask upper space.
(3) In the above (2), a hole is formed in the top of the parabolic mirror, and the communication hole provided in the purge box is the hole formed in the top of the parabolic mirror. Part (gap between the through hole and the lamp outer surface).
(4) In the above (1), (2), and (3), the light passing through the passage hole is passed through the light shielding plate that shields the light emitted from the short flash lamp above the passage hole. It arrange | positions through the opening surface of a hole, and a clearance gap.

In the present invention, the following effects can be obtained.
(1) Since the vacuum ultraviolet short arc flash lamp which is a point light source and a parabolic mirror are mounted, it is possible to take out the vacuum ultraviolet light which is parallel light or substantially parallel light. In addition, by constructing an illumination optical system using this parallel light or substantially parallel light and performing exposure with less light wraparound, it is possible to realize patterning with a pattern size of several μm or less, and excimer laser It is cheaper than the apparatus, and a practical vacuum ultraviolet light irradiation processing apparatus can be realized from the viewpoint of COO.
(2) Since the optical path space including the inside of the lamp housing and the processing chamber is purged of oxygen by an inert gas such as N ₂ gas, the attenuation of the vacuum ultraviolet light intensity due to the absorption by oxygen is suppressed significantly. Further, since ozone generated by absorption of vacuum ultraviolet light by oxygen is not generated, oxidative deterioration of components in the lamp housing does not occur. Furthermore, since the purge gas exhausted outside the lamp housing does not contain ozone, it is not necessary to separately provide an ozone filter, and the apparatus configuration can be simplified.
(3) Since a passage hole for spatially connecting the inside of the lamp housing and the upper space of the mask of the processing chamber is provided, the inert gas purge performed for the lamp housing and the upper space of the mask is supplied with one common gas supply / It is possible to perform simultaneously using the exhaust system, and it is possible to simplify the apparatus configuration.
(4) Since a light shielding plate is provided above the passage hole, irradiation of VUV light to an undesired place in the processing chamber is prevented, and deterioration of the irradiated portion caused by irradiation with vacuum ultraviolet light is prevented. Is suppressed.
(5) Provided in the lamp housing is a purge box containing a lamp, a parabolic mirror, an opening of a passage hole provided between the lamp housing and the mask upper space A of the processing chamber, and a quartz window. An inert gas such as N ₂ gas is supplied from the gas inlet to the purge box, and a communication hole such as a gap between the top through hole of the parabolic mirror and the outer surface of the lamp is supplied from the inside of the purge box. In addition, since an inert gas such as N ₂ gas is supplied to the space outside the purge box inside the lamp housing and the mask upper space A through the passage hole, Oxygen can be purged with an inert gas in a short time from the optical path until the light reaches the quartz window and the optical path space in the mask upper space A.
(6) Since the purge box is first purged with an inert gas such as N ₂ gas, a gas (air) containing oxygen present in the space outside the purge box does not enter the purge box. If the airtightness in the purge box is ensured, the sealing structure of the relatively large lamp housing can be a simple structure.
(7) Since the vacuum ultraviolet light irradiation processing apparatus of the present invention can irradiate a work with vacuum ultraviolet light as parallel light, for example, it becomes possible to directly expose a SAM film provided on the work surface, Since a developing process using a photoresist is not required as in the prior art, the exposure process can be simplified.

It is a figure which shows the structural example of the vacuum ultraviolet light irradiation processing apparatus which is the 1st Embodiment of this invention. It is a figure which shows the structural example of the short arc flash lamp which discharge | releases a vacuum ultraviolet light. It is a figure which shows an example of the spectral radiation spectrum of the light discharge | released from a flash lamp. It is a figure which shows 2nd Embodiment of the vacuum ultraviolet light irradiation processing apparatus of this invention. It is a figure which shows 3rd Embodiment of the vacuum ultraviolet light irradiation processing apparatus of this invention. It is a figure which shows the structural example which incorporated the VUV short arc flash lamp which discharge | releases a vacuum ultraviolet light in the conventional ultraviolet irradiation processing apparatus.

[First Embodiment]
FIG. 1 shows a configuration example of a vacuum ultraviolet light irradiation processing apparatus according to the first embodiment of the present invention.
The main component of the vacuum ultraviolet light irradiation processing apparatus of this embodiment is the same as that of the ultraviolet irradiation processing apparatus shown in FIG. 6, and a VUV short arc flash lamp 1 (VUV) that emits vacuum ultraviolet light into the lamp housing 3. -SFL), a parabolic mirror 2, and a part of the power supply means 11 for supplying a trigger pulse for starting and power to the VUV-SFL1. The power supply means 11 includes a capacitor charged with energy, a power supply unit 13 including a step-up transformer, a trigger circuit unit 12 for generating a start trigger pulse, and a charger 14 for charging the capacitor of the power supply unit 13. The power supply unit 13 and the trigger circuit unit 12 are installed inside the lamp housing 3.

The flash lamp 1 is arranged so that the position of the light emitting part (short arc generating part between the electrodes) substantially coincides with the position of the focal point of the parabolic mirror 2. Specifically, the flash lamp 1 is inserted through a through-hole provided at the top of the parabolic mirror 2, and the position of the light emitting portion of the flash lamp 1 and the focal position of the parabolic mirror 2 are substantially coincident. Thus, the flash lamp 1 is arranged. That is, there is a gap of a certain distance between the through hole at the top of the parabolic mirror 2 and the outer surface of the flash lamp 1. As will be described later, an inert gas such as N ₂ flowing from the first gas inlet 3a flows through this gap as shown by the dotted arrow in FIG. 1, and cools the lamp 1, the parabolic mirror 2, and the like. To do. Hereinafter, this gap is also referred to as a communication hole 2a.

FIG. 2 shows a configuration example of a short arc flash lamp that emits vacuum ultraviolet light that can be applied to the present invention.
As shown in the figure, in the flash lamp 1 used in the present invention, a distance L between a pair of electrodes 1a is 12.5 mm or less in an arc tube (quartz glass tube 1b) made of a vacuum ultraviolet light transmitting material. A gas containing xenon gas is enclosed in the arc tube, and the enclosed gas is 2 to 8 atm. The power supply means for supplying power to the flash lamp is from the start of discharge until the current value reaches a peak value. Is designed to have a current value of 1500 A or more when the peak value is reached. The arc tube is provided with sealing portions 1d for sealing the external leads 1c extending from the pair of electrodes 1a.
The time from the start of discharge until the current value reaches the peak value is adjusted by adjusting the capacitance of the capacitor, the impedance of the circuit, and the reactance. Specifically, the capacitance of the capacitor is 20 μF, the impedance of the circuit is 23 mΩ, The reactance is 0.65 μH. In order to realize such low circuit impedance and circuit reactance, the capacitor is placed close to the lamp in the lamp house.
Also, the wiring distance between the lamp and the capacitor involved in the discharge is designed to be as short as possible.

FIG. 3 shows an example of the spectral emission spectrum of the light emitted from the flash lamp 1. The horizontal axis represents the wavelength, and the vertical axis represents the spectral radiation intensity. The figure shows the spectral radiation spectrum when the pressure inside the arc tube is 3 atm (3.04 × 10 ⁵ Pa). As is apparent from FIG. 3, the light emitted from the flash lamp includes light having a wavelength of 200 nm or less, and in particular, the light intensity near the wavelength of 170 nm is increased. This is presumably because the emission of Xe excimer has increased.

Returning to FIG. 1, the light emitted from the flash lamp 1 is collimated by the parabolic mirror 2 and then emitted from the quartz window 4 to the outside of the lamp housing 3. The light transmissive window that transmits the light emitted from the flash lamp 1 is configured as, for example, a quartz window 4 made of synthetic quartz having high transmittance for VUV light. If necessary, sapphire glass, calcium fluoride, or magnesium fluoride having a shorter wavelength than quartz can be used as the material of the light transmissive window.
Moreover, aluminum is vapor-deposited on the inner surface (light reflecting surface) of the parabolic mirror 2 to form an aluminum reflecting film. Aluminum is suitable as a mirror material because it has a characteristic of efficiently reflecting VUV.

The quartz window 4 is assembled airtight with the lamp housing 3, and the inside of the lamp housing 3 is purged by introducing an inert gas such as N ₂ gas from a first gas inlet 3 a provided in the lamp housing 3. . The flow of wind due to an inert gas such as N ₂ gas introduced into the lamp housing 3 is shown in FIG. The lamp 2 reaches the flash lamp 1 through a gap (communication hole 2 a) between the top through hole of the parabolic mirror 2 and the outer surface of the flash lamp 1, and after cooling these, the lamp housing 3 is provided. The air is exhausted from the first exhaust port 3b.

  A processing chamber 5 that holds a workpiece W irradiated with VUV light is provided below the quartz window 4 from which VUV light is extracted from the lamp housing 3. In the processing chamber 5, a work stage 7 that holds the work W is provided on the bottom surface thereof. Further, as described above, the SAM film is applied to the surface of the workpiece W, and when the SAM film is patterned, a transfer pattern to the surface of the workpiece W is applied between the workpiece W and the quartz window portion 4. A mask 6 is provided.

Here, as shown in FIGS. 1A and 1B, at least one that spatially connects the interior space of the lamp housing 3 and the interior of the processing stage 5 around the quartz window portion 4 of the lamp housing 3. The above passage holes 3c (12 places in the figure) are provided.
The inside of the processing chamber 5 for processing the workpiece W is divided into a mask upper space A, which is a space between the quartz window portion 4 and the mask 6, and a workpiece processing space B in which the workpiece W on the lower surface of the mask 6 is installed. It is divided into airtight. Therefore, although the passage hole 3c spatially connects the inside of the lamp housing 3 and the mask upper space A, the mask upper space A and the work processing space B are not in communication. The mask upper space A is provided with a second exhaust port 5a.

With the above structure, the inert gas such as N ₂ gas introduced into the lamp housing 3 from the first gas inlet 3a is supplied to the power supply means 11 (power supply unit 13, trigger circuit unit 12), flash lamp 1 and parabolas. After the surface mirror 2 is cooled, it is exhausted from the first exhaust port 3 b provided in the lamp housing 3, and a part of it passes through the passage hole 3 c and purges the atmosphere from the mask upper space A of the processing chamber 5. 2 is exhausted from the exhaust port 5a.

  In this way, by providing the passage hole 3c that spatially connects the inside of the lamp housing 3 and the processing chamber 5 (mask upper space A), the lamp housing 3 and the mask upper space A in FIG. It is possible to simultaneously perform the inert gas purge using one common gas supply / exhaust system. Therefore, the configuration of the vacuum ultraviolet light irradiation processing apparatus can be simplified.

As described above, the patterning process of the workpiece W having the patterning process layer such as the SAM film on the surface is performed by irradiating the VUV light transmitted through the mask 6. Here, depending on the patterning process layer, if oxygen is present in the vicinity of the process layer surface, the patterning speed may increase. Therefore, the work processing space B is appropriately set to an atmosphere containing oxygen to the extent that the decrease in the VUV light intensity on the surface does not become significant depending on the material of the patterning processing layer on the work W.
In this case, a gas containing oxygen is introduced into the work processing space B from the second gas introduction port 5b, the work processing space B is purged by the gas, and is exhausted from the third gas exhaust port 5c. In FIG. 1, the spatially connected lamp housing 3 and mask upper space A are purged with an inert gas such as N ₂ gas, and the work processing space B is purged with a mixed gas composed of nitrogen and oxygen. An example is shown.

[Second Embodiment]
The VUV light contained in the light emitted from the flash lamp (VUV-SFL) 1 has a large energy due to its short wavelength, and when an undesired portion in the vacuum ultraviolet light irradiation processing apparatus is irradiated with the VUV light, Deterioration of the irradiated part may occur.
For example, a part of the VUV light that passes through the passage hole 3c that spatially connects the inside of the lamp housing 3 and the processing chamber 5 (mask upper space A) may cause the mask 6 outside or the mask 6 to be affected by diffraction or the like. There is a possibility that an undesired location such as the outside of the workpiece W is irradiated to cause deterioration of a portion for holding the mask 6 or a workpiece stage 7 on which the workpiece W is placed.

The second embodiment of the vacuum ultraviolet light irradiation processing apparatus of the present invention shown in FIG. 4 prevents irradiation of an undesired portion of the processing chamber 5 by the VUV light passing through such a passage hole 3c. is there. Specifically, a light shielding plate 3d that shields the irradiation of the VUV light to the passage hole 3c is provided above the passage hole 3c. Here, the light shielding plate 3d does not completely close the passage hole 3c, but is installed with a gap with respect to the upper surface of the passage hole 3c.
With this structure, the VUV light passing through the passage hole 3c in FIG. 1 is shielded, but the flow of an inert gas such as N ₂ gas passing through the passage hole 3c is secured.
The light shielding plate 3d is preferably made of a material having high durability against VUV light, and is made of, for example, aluminum whose surface is subjected to black plating treatment (for example, black alumite treatment, black chrome treatment). The reason why the black plating process is performed on the aluminum surface is to suppress the scattering of VUV light on the surface of the light shielding plate 3d.

[Third Embodiment]
FIG. 5 shows a third embodiment of the vacuum ultraviolet light irradiation processing apparatus of the present invention.
In the first and second embodiments shown in FIGS. 1 and 4, the lamp housing 3 includes a power supply unit 11 (power supply unit 13 and trigger circuit unit 12), a parabolic mirror 2, a flash lamp (VUV−). SFL) 1 and many components are included, and the size becomes relatively large.
In such a configuration, an inert gas such as N ₂ gas is introduced from the first gas inlet 3a and is spatially connected to the inside of the lamp housing 3 and the inside of the lamp housing 3 through the passage hole 3c. It takes time to purge oxygen from the processing chamber 5 (mask upper space A). That is, it takes a long time to prepare for the vacuum W irradiation process such as the patterning process on the workpiece W.

  Naturally, since the inflow of oxygen-containing air into the lamp housing 3 from the external atmosphere (atmospheric atmosphere) where the vacuum ultraviolet light irradiation treatment apparatus is installed must be prevented, the lamp housing 3 is made of, for example, a metal material. A large-scale sealing structure such as welding is required.

In the third embodiment shown in FIG. 5, a small purge box 3 e is provided in the lamp housing 3. The purge box 3e includes at least a part of the parabolic mirror 2, a light emitting portion of the VUV-SFL1, an opening portion of a passage hole 3c that spatially connects the inside of the lamp housing 3 and the processing chamber 5 (mask upper space A), A quartz window 4 is included. A gas supply pipe 3f constituting a first gas inlet 3a for supplying an inert gas such as N ₂ gas is inserted into the purge box 3e, and the inert gas is first supplied into the purge box 3e. Is done.

The wind made of an inert gas such as N ₂ gas supplied into the purge box 3e passes through the gap (communication hole 2a) between the top through hole of the parabolic mirror 2 and the outer surface of the VUV-SFL 1. Thus, the flow proceeds to the outside of the purge box 3e, passes through the space outside the purge box 3e inside the lamp housing 3, and is exhausted to the outside through the first exhaust port 3b. At that time, an inert gas such as N ₂ gas cools the power supply means 11 (power supply unit 13 and trigger circuit unit 12) disposed inside the lamp housing 3 and outside the purge box 3e.
In addition, the air made of an inert gas such as N ₂ gas supplied into the purge box 3e purges the atmosphere from the mask upper space A of the processing chamber 5 through the passage hole 3c, and the second exhaust port 5a. The flow is more exhausted.

According to the third embodiment, at least a part of the parabolic mirror 2 in the lamp housing 3, the light emitting part of the flash lamp (VUV-SFL) 1, the inside of the lamp housing 3, and the processing chamber 5 (mask upper space A). And a purge box 3e containing the quartz window 4 and a gas supply pipe for supplying an inert gas such as N ₂ gas to the purge box 3e. The purge box is inserted into the purge housing 3 via the gap (communication hole 2a) between the inside of the purge box 3e and the through hole at the top of the parabolic mirror 2 and the outer surface of the flash lamp 1, or the passage hole 3c. 3e since the outside of the space or processing chamber 5 (mask the upper space a) so as to supply an inert gas such as N ₂ gas, the first embodiment, and those of the second embodiment In comparison, the optical path from the light emitting part of the VUV-SFL 1 to the reflecting surface of the parabolic mirror 2, the optical path until the parallel light from the parabolic mirror 2 reaches the quartz window part 4, and the quartz window part 4. Oxygen can be purged with an inert gas such as N ₂ gas in a short time from the optical path space including the optical path until the light reaches the mask 6.

Further, the optical path of the VUV light is first purged with an inert gas such as N ₂ gas, and then the space outside the purge box 3e in the lamp housing 3 is purged with the inert gas released to the outside of the purge box 3e. Therefore, the gas (air) containing oxygen existing in the space outside the purge box 3e in the lamp housing 3 does not enter the VUV optical path space inside the purge box 3e.

  Therefore, if the airtightness in the purge box 3e is ensured, the airtight structure of the lamp housing 3 that is relatively large is, for example, a simple structure in which a metal sheet metal is fixed to a column such as an angle by screwing. It becomes possible.

  The light emitted from the ultraviolet lamp used in the conventional ultraviolet irradiation processing apparatus has a large proportion of light having a wavelength in the infrared region, and the lamp peripheral member (for example, the parabolic mirror 2) is heated during light emission. Is done. Therefore, when the lamp 1 and the parabolic mirror 2 are first cooled by the cooling gas and then the inside of the lamp housing 3 is to be cooled, the temperature of the inert gas is increased by heat exchange with the lamp 1 and the parabolic mirror 2. Ascending, it becomes difficult to cool the other components in the lamp housing 3. Therefore, normally, after cooling components other than the lamp 1 and the parabolic mirror 2, the cooling gas flow is set so that the lamp 1 and the parabolic mirror 2 are cooled.

However, in the case of VUV-SFL1, the light emitted from VUV-SFL1 has a large proportion of light having a wavelength in the vacuum ultraviolet region and the ultraviolet region, and a relatively small proportion of light having a wavelength in the infrared region. Therefore, as in the third embodiment, the wind made of an inert gas such as N ₂ gas supplied into the purge box 3e is passed through the through hole at the top of the parabolic mirror 2 and the outer surface of the VUV-SFL 1 The flow proceeds to the outside of the purge box 3e through the gap (communication hole 2a), passes through the outer space of the purge box 3e inside the lamp housing 3, and is exhausted to the outside through the first exhaust port 3b. However, the temperature of the inert gas such as N ₂ gas that travels inside the lamp housing 3 and outside the purge box 3e does not increase so much. Therefore, the inert gas can cool the power supply means 11 (power supply unit 13 and trigger circuit unit 12) disposed inside the lamp housing 3 and outside the purge box 3e.

  As described above, the vacuum ultraviolet light irradiation processing apparatus of the present invention is equipped with the vacuum ultraviolet short arc flash lamp 1 (VUV-SFL1) which is a point light source that emits vacuum ultraviolet light (VUV light). It is possible to extract light that is parallel light or substantially parallel light. Then, it is possible to realize patterning with a pattern size of several μm or less by constructing an illumination optical system using the above-described parallel light or substantially parallel light and performing exposure with less light wraparound. Such a light source device is cheaper than an excimer laser device and is a practical light source device from the viewpoint of COO.

Further, light including VUV emitted from the light emitting part of the VUV-SFL 1, reflected as parallel light by the parabolic mirror 2, passes through the quartz window part 4 of the lamp housing 3 and reaches the mask 6 of the processing chamber 5. Since oxygen is purged by an inert gas such as N ₂ gas in the optical path space that passes, the attenuation of the VUV intensity due to absorption by oxygen is also suppressed. Further, since ozone generated by the absorption of VUV light by oxygen is not generated, oxidative deterioration of components in the lamp housing 3 (for example, electronic components such as a power supply line (wiring member), a trigger board, and a capacitor) is also prevented. Does not occur.
Further, since ozone is not included in the purge gas exhausted outside the lamp housing 3, it is not necessary to provide an ozone filter separately.

  In particular, the vacuum ultraviolet light irradiation processing apparatus of the present invention is provided with the passage hole 3c that spatially connects the inside of the lamp housing 3 and the processing chamber 5 (mask upper space A). It is possible to simultaneously perform the inert gas purge performed for the gas using a common gas supply / exhaust system. Therefore, the configuration of the vacuum ultraviolet light irradiation processing apparatus can be simplified.

Further, by providing a light shielding plate 3d above the passage hole 3c with a gap with respect to the upper surface of the passage hole 3c, the VUV light passing through the passage hole 3c is shielded, and the VUV light passes through the passage hole 3c. In such a case, irradiation of VUV light to an undesired place in the processing chamber 5 that occurs in this case is prevented. Therefore, deterioration of the irradiated portion (for example, deterioration of the portion holding the mask 6 or the work stage 7 on which the workpiece W is placed) generated by the irradiation with VUV light is also suppressed. In addition, since the light shielding plate 3d is installed through a gap with respect to the upper surface of the passage hole 3c, the passage hole 3c is not completely closed. Therefore, the flow of an inert gas such as N ₂ gas passing through the passage hole 3c is ensured.

Furthermore, at least a part of the parabolic mirror 2 in the lamp housing 3, the light emitting part of the VUV-SFL 1, and a passage hole 3 c that spatially connects the inside of the lamp housing 3 and the processing chamber 5 (mask upper space A). A purge box 3e containing the opening and the quartz window 4 is provided, and a gas supply pipe 3f for supplying an inert gas such as N 2 gas is inserted into the purge box 3e, and a parabolic mirror is inserted into the purge box 3e. 2 between the through hole at the top of V 2 and the outer surface of the VUV-SFL 1 (communication hole 2 a), the space inside the lamp housing 3 through the passage hole 3 c and outside the purge box 3 e and the work processing space B (the upper part of the mask) By supplying an inert gas such as N ₂ gas to the space A), the optical path from the VUV-SFL1 light emitting part to the reflecting surface of the parabolic mirror 2, the parabolic mirror Optical path to the parallel light from the 2 reaches the quartz window 4, the optical path space which encloses the optical path to the light that has passed through the quartz window 4 reaches the mask 6, such as a short time N ₂ gas not It becomes possible to purge oxygen with the active gas.

Further, the optical path of the VUV light is first purged with an inert gas such as N ₂ gas, and then the space outside the purge box 3e in the lamp housing 3 is opened by the inert gas released to the outside of the purge box 3e. Since the purge is performed, the gas (air) containing oxygen present in the space outside the purge box 3e in the lamp housing 3 does not enter the VUV optical path space inside the purge box 3e.

  Therefore, if the airtightness in the purge box 3e is ensured, the airtight structure of the lamp housing 3 that is relatively large is, for example, a simple structure in which a metal sheet metal is fixed to a column such as an angle by screwing. It becomes possible.

  Since such a vacuum ultraviolet light irradiation processing apparatus can irradiate the workpiece W with VUV light as parallel light, for example, a SAM film provided on the surface of the workpiece W can be directly exposed, for example. In this case, since a developing process using a photoresist is not required as in the prior art, the exposure process can be simplified.

1 Flash lamp (VUV-SFL)
1a Electrode 1b Quartz glass tube 1c External lead 1d Sealing part 2 Parabolic mirror 2a Communication hole 3 Lamp housing 3a First gas inlet 3b First exhaust port 3c Passing hole 3d Light shielding plate 3e Purge box 3f Supply tube 4 Quartz window portion 5 Processing chamber 5a Second exhaust port 5b Second gas introduction port 5c Third exhaust port 6 Mask 7 Work stage 11 Power supply means 12 Trigger circuit unit 13 Power supply unit A Mask upper space B Work processing space W Workpiece

Claims (4)

A short arc flash lamp that emits light including at least vacuum ultraviolet light, and a parabolic mirror that emits light emitted from the short flash lamp as parallel light in one direction are disposed inside, and an inert gas is contained therein. A lamp housing having a gas inlet to which is supplied;
A light transmissive window portion that is provided in the lamp housing and transmits parallel light emitted from the parabolic mirror;
From a mask irradiated with parallel light that has passed through the light transmissive window, a work irradiated with the parallel light through the mask, and a processing chamber in which a work stage holding the work is disposed. A vacuum ultraviolet light irradiation treatment device comprising:
The inside of the processing chamber is masked, and a mask upper space surrounded by a surface including the upper surface of the mask and the light emitting surface of the light transmitting window, and a work and a work stage are disposed on the lower surface side of the mask. In the vacuum ultraviolet light irradiation processing apparatus which is divided into a work processing space in an airtight manner and the work processing space is supplied with a work processing gas,
One or more passage holes for spatially connecting the interior of the lamp housing and the space above the mask are provided,
A vacuum ultraviolet light irradiation processing apparatus, wherein a gas exhaust port through which an inert gas supplied into the lamp housing passes through the passage hole and is exhausted to the outside is provided in the upper space of the mask. A short arc flash lamp that emits light including vacuum ultraviolet light, a parabolic mirror that emits light emitted from the short flash lamp as parallel light in one direction, a trigger pulse for starting the short flash lamp, and A lamp housing in which a power supply device for supplying electric power is disposed;
A light transmissive window portion that is provided in the lamp housing and transmits parallel light emitted from the parabolic mirror;
From a mask irradiated with parallel light that has passed through the light transmissive window, a work irradiated with the parallel light through the mask, and a processing chamber in which a work stage holding the work is disposed. A vacuum ultraviolet light irradiation treatment device comprising:
The inside of the processing chamber is masked, and a mask upper space surrounded by a surface including the upper surface of the mask and the light emitting surface of the light transmitting window, and a work and a work stage are disposed on the lower surface side of the mask. In the vacuum ultraviolet light irradiation processing apparatus which is divided into a work processing space in an airtight manner and the work processing space is supplied with a work processing gas,
One or more passage holes for spatially connecting the inside of the lamp housing and the mask upper space are provided,
The lamp housing contains at least a part of the parabolic mirror, the light emitting part of the short arc flash lamp, the opening of the passage hole, and a quartz window, and has a communication hole between the lamp housing and the lamp housing. A purge box is provided,
The purge box has a gas introduction port through which inert gas is supplied into the inside inserted through the lamp housing, and the inert gas is supplied into the purge box from the gas introduction port,
The inert gas supplied into the purge box by the gas introduction port is supplied to the space outside the purge box in the lamp housing through the communication hole, and to the mask upper space through the passage hole. Supplied to
A vacuum ultraviolet light irradiation processing apparatus, wherein a gas exhaust port through which an inert gas supplied into the lamp housing passes through the passage hole and is exhausted to the outside is provided in the upper space of the mask. A hole is formed at the top of the parabolic mirror,
The vacuum ultraviolet light irradiation processing apparatus according to claim 2, wherein the communication hole provided in the purge box is the hole formed at the top of the parabolic mirror. A light-shielding plate that shields light emitted from the short flash lamp is disposed above the passage hole via an opening surface of the passage hole and a gap so as to block the passage of the light through the passage hole. The vacuum ultraviolet light irradiation processing apparatus according to claim 1, 2 or 3.

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