JP2007251147A - Exposure method and method for preparing semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exposure method that eliminates problems such as positioning and complicatedness in designing a mask original plate or the like even if a more micro-pattern is formed into a resist by contracting a pattern of the mask original plate. <P>SOLUTION: A hologram recording medium where the hologram of a first pattern is recorded by irradiating laser beam oscillated from a first laser oscillator includes a process that irradiates the laser beam oscillated from a second laser oscillator and a process that forms a second pattern on the resist by allowing the laser beam oscillated from the second laser oscillator to pass through the hologram recording medium to irradiate it to the resist. Further a wavelength of the laser beam irradiated to the resist is more shortened than the laser beam irradiated to record a hologram on the hologram recording medium, and should be inverse severalfold n times (n is an integer that is 3 or higher) of 0.5 of the wavelength of a laser beam irradiated to record the hologram. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an exposure method and a method for manufacturing a semiconductor device using the exposure method, and more particularly to an exposure method using holography.

  In recent years, an exposure technique using holography has attracted attention as a method for forming a pattern in a manufacturing process of a semiconductor device. The exposure technology using holography includes a process of recording a hologram by irradiating a medium for recording a hologram (hereinafter referred to as “hologram recording medium”) with object light and reference light (recording process), and hologram recording. And a step (reproduction step) of forming a reproduction image of a hologram on an irradiation object such as a resist by irradiating the medium with reproduction light.

  In the recording process, the hologram recording medium is irradiated with a first laser beam (object beam) through a mask on which a desired pattern is formed, and a second laser beam (see reference) from a direction different from the first laser beam. Light). Then, by irradiating the hologram storage medium with the first laser beam and the second laser beam simultaneously, interference fringes of the first laser beam and the second laser beam are formed on the hologram recording medium. On the other hand, in the reproduction process, the hologram recording medium is irradiated with laser light as reproduction light, and the resist is exposed by forming an image of diffracted light that reproduces the original pattern on the resist formed on the substrate.

In the recording process and the reproducing process of the exposure technology using holography, research on the method of forming a finer original pattern on the resist by using laser light oscillated from different types of laser oscillators has been conducted. Yes. (For example, Patent Document 1)
JP 2004-253660 A

  However, various studies on reduction exposure using holography have been conducted so far, but there are not enough studies on the formation of a device in combination with mask design and other exposure methods in actual device miniaturization. .

For example, when a pattern having a width of 0.5 μm is formed on a resist, the third harmonic (wavelength 355 nm) of an Nd: YAG laser is used as a recording light source, and an F ₂ laser (wavelength 157 nm) is used as a reproduction light source. ), The magnification of the recording light wavelength with respect to the reproduction light is 2.26 times. In this case, the mask original pattern must be 1.13 μm (0.5 μm × 2.26), and the minimum unit of the pattern width is 0.01 μm. As a result, there is a problem that the design and data reading time becomes long. Furthermore, since the processing accuracy of the pattern formed on the mask original plate is required, the cost may increase.

  In addition, when the processing accuracy of the pattern formed on the mask original plate is not sufficient, there is a risk of affecting the alignment in manufacturing the device. This problem becomes more conspicuous when a device is manufactured by miniaturization of the device or by combining reduction exposure using holography with another exposure apparatus such as a stepper or MPA (Mirror Projector Aligner).

  In view of the above problems, the present invention eliminates the problem of alignment and the complexity of the design of the mask original plate even when the pattern formed on the mask original plate is reduced to form a finer pattern on the resist. It is an object of the present invention to provide an exposure method to be performed and a method for manufacturing a semiconductor device using the exposure method.

In the exposure method of the present invention, the laser beam oscillated from the second laser oscillator is applied to the hologram recording medium on which the hologram having the first pattern is recorded by being irradiated with the laser beam oscillated from the first laser oscillator. And irradiating the resist with laser light oscillated from the second laser oscillator through the hologram recording medium, and forming a second pattern on the resist. The wavelength of the laser beam irradiated to the resist through the hologram recording medium is made shorter than the wavelength of the laser beam irradiated to record the hologram on the hologram recording medium, and the wavelength of the laser beam irradiated to record the hologram The reciprocal of 0.5 times n (n is an integer of 3 or more). That is, λ _{1 is} the wavelength of the laser light that is emitted from the _first laser oscillator and then is applied to the hologram recording medium, and λ _{2 is} the wavelength of the laser light that is emitted from the second laser oscillator and is applied to the hologram recording medium. Λ ₂ satisfies the following relationship: λ ₁ > λ ₂ and λ ₂ = λ ₁ /(0.5×n) (n is an integer of 3 or more). Irradiation of laser light oscillated from the laser oscillator of.

  In addition, a method for recording a hologram having a first pattern on a hologram recording medium forms a first laser beam and a second laser beam by dividing a laser beam oscillated from a first laser oscillator. The hologram recording medium is irradiated with one of the laser beams (for example, the first laser beam) through the mask on which the first pattern is formed, and at the same time, the other laser beam (for example, the second laser beam) is holograms This can be done by irradiating the recording medium. On the hologram recording medium, interference fringes are formed by simultaneously irradiating the first laser beam and the second laser beam. The hologram recording medium on which the interference fringes are formed is irradiated with the third laser light oscillated from the second laser oscillator, and the resist is irradiated with the third laser light that has passed through the hologram recording medium. Thus, the second pattern can be formed on the resist.

In the above structure, the wavelength of the third laser light is shorter than the wavelengths of the first laser light and the second laser light, and the wavelengths of the first laser light and the second laser light are set to the third laser light. The wavelength is an integral multiple of 0.5. As the first laser oscillator and the second laser oscillator, different types of laser oscillators may be used, the same type of laser oscillators may be used, or exactly the same laser oscillators may be used. In this specification, using the same type of laser oscillator means that a laser oscillator that oscillates laser light of the same wavelength, although the laser oscillator itself is different (for example, YAG laser and YAG laser, or YVO ₄ laser and YVO _4). Laser), and using the same laser oscillator means using the same laser oscillator.

The exposure method of the present invention is characterized in that a solid-state laser oscillator is used as a laser oscillator. In particular, a YAG laser oscillator, a YVO ₄ laser oscillator, a YLF laser oscillator, a YAlO ₃ laser oscillator, or a GdVO is used as the solid-state laser oscillator. _{A 4-} laser oscillator or the like can be used.

  A method for manufacturing a semiconductor device of the present invention includes a step of forming a semiconductor film on a substrate, a step of forming a conductive film over the semiconductor film, a step of forming a resist on the conductive film, and a first laser oscillator A step of irradiating a laser beam oscillated from the second laser oscillator onto a hologram recording medium on which a hologram of the first pattern is recorded by irradiating the laser light oscillated from the second laser oscillator; A process of forming a second pattern on the resist by irradiating the resist with the oscillated laser light passing through the hologram recording medium, and irradiating the resist through the hologram recording medium on which the hologram has been recorded. The wavelength of the laser beam is made shorter than the wavelength of the laser beam irradiated for recording the hologram on the hologram recording medium, and the hologram 0.5 n times the wavelength of the laser beam irradiated for recording (n is an integer of 3 or more) and reciprocal of the.

  The method for manufacturing a semiconductor device of the present invention includes a step of forming a semiconductor film on a substrate, a step of forming a conductive film over the semiconductor film, a step of forming a resist on the conductive film, A step of irradiating a hologram recording medium on which a hologram having a first pattern is recorded by being irradiated with laser light oscillated from a laser oscillator; and a second laser. A process of forming a second pattern on the resist by irradiating the resist with laser light oscillated from an oscillator through the hologram recording medium, and the same type as the first laser oscillator and the second laser oscillator The wavelength of the laser beam that passes through the hologram recording medium on which the hologram is recorded and irradiates the resist with the laser oscillator Shorter than the wavelength of the laser beam irradiated for recording a hologram in ram recording medium, and the hologram is a harmonic is used as the laser beam irradiated to the recorded hologram recording medium.

  By using the exposure method of the present invention, even when the pattern formed on the mask original plate is reduced and the resist is exposed, the problem of alignment and the complexity of the design of the mask original plate can be solved. it can. Further, when a device such as a semiconductor device is manufactured using the exposure method of the present invention, alignment can be performed with high accuracy even if a different exposure method is used in the manufacturing process.

  Embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited to the following description, and it is easily understood by those skilled in the art that modes and details can be variously changed without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments below. Note that in the structures of the present invention described below, the same reference numerals may be used in common in different drawings.

(Embodiment 1)
In the present embodiment, an example of the exposure method of the present invention using holography will be described with reference to the drawings. Specifically, the steps of recording the mask original pattern on the hologram recording medium and the steps of transferring the hologram recorded on the hologram recording medium to a resist formed on the substrate and reproducing it are shown in FIGS. 2 will be described.

  First, FIG. 1 shows an example of an exposure apparatus used in this embodiment.

  The exposure apparatus shown in FIG. 1 includes a laser oscillator 101, a beam splitter 102 that divides laser light emitted from the laser oscillator 101, mirrors 103 and 106 that reflect the laser light in a desired direction, and a scale of the laser light. Enlarging optical systems 104 and 105 for enlarging and stages 112a and 113a are provided.

  The stage 112a and the stage 113a are provided in order to place a sample used for exposure, and the position can be adjusted in the vertical direction and the horizontal direction. Here, as an example, a mask original plate 108 is arranged on the stage 112a and a hologram recording medium 111 is arranged on the stage 113a.

  Next, a process (recording process) of recording the pattern of the mask original 108 on the hologram recording medium 111 using the exposure apparatus shown in FIG. 1 will be described.

  The laser light oscillated from the laser oscillator 101 is split into laser light having an appropriate intensity ratio by the beam splitter 102. Here, the light is divided into a first laser beam 114a and a second laser beam 114b. Thereafter, the scale of the first laser beam 114 a is enlarged by the magnifying optical system 105, and then enters the hologram recording medium 111 as the object beam 109 through the mask original plate 108 formed on the substrate 107. On the other hand, the second laser beam 114 b is incident on the hologram recording medium 111 as the reference beam 110 after the scale is enlarged by the magnification optical system 104. As described above, when the object light 109 and the reference light 110 are simultaneously irradiated onto the hologram recording medium 111, interference fringes between the object light 109 and the reference light 110 are formed on the hologram recording medium 111. That is, the hologram having the pattern of the mask original plate 108 is recorded on the hologram recording medium 111. Note that a computer generated hologram in which interference fringes obtained by calculation may be used instead of the hologram recording medium 111 in which interference fringes are formed by laser light irradiation.

As the laser oscillator 101, a solid-state laser such as YAG laser, YVO ₄ laser, YLF laser, YAlO ₃ laser, GdVO ₄ laser, or the like can be used. Specifically, a solid-state laser using a crystal in which Cr, Nd, Er, Ho, Ce, Co, Ti, or Tm is doped in a crystal such as YAG, YVO ₄ , YLF, YAlO ₃ , GdVO ₄ or the like is used. In the present invention, the fundamental wave to the fifth harmonic of these solid-state laser oscillators are selectively applied according to use. The harmonic with respect to the fundamental wave can be obtained by using a nonlinear optical element.

  Next, FIG. 2 shows an example of a process (reproduction process) in which the hologram recorded on the hologram recording medium 111 formed in FIG. 1 is transferred to a resist and reproduced.

  The laser beam oscillated from the laser oscillator 121 is modulated into a harmonic by the nonlinear optical element 122 to become a laser beam 131. The laser light 131 modulated into the harmonic is then changed in traveling direction by the mirror 123, and then the scale of the laser light 131 is expanded by the magnifying optical system 124. Then, after the traveling direction is changed by the mirrors 125 and 126, it enters the hologram recording medium 111 as reproduction reference light 127. The reproduction reference light 127 incident on the hologram recording medium 111 is diffracted by the interference fringes formed on the hologram recording medium 111, and a part of the reproduction reference light 127 is incident on the resist 130 provided on the substrate 129. Here, the substrate 129 is disposed on the stage 112b, and the hologram recording medium 111 on which interference fringes are formed is disposed on the stage 113b. The reproduction reference beam 127 is incident on the hologram recording medium 111 from the opposite direction to the reference beam 110 shown in FIG. 1, and the resist 130 is disposed at the position where the mask original plate 108 shown in FIG.

  In the reproducing step shown in FIG. 2, the first laser beam 114a used in the recording step shown in FIG. 1 and the laser beam 131 used when transferring the hologram recorded on the hologram recording medium 111 to the resist 130, and The wavelength is shorter than that of the second laser beam 114b, and the wavelength is the inverse of 0.5 times the wavelength of the first laser beam 114a and the second laser beam 114b (n is an integer of 3 or more). Use laser light. The wavelength of the laser beam 131 is a wavelength of the laser beam that is a reciprocal of n times 0.5 (n is an integer of 3 or more) of the wavelengths of the first laser beam 114a and the second laser beam 114b. Even if they are not completely the same, they may be shifted within a range that can be identified by those skilled in the art. Here, the harmonics of the first laser beam 114a and the second laser beam 114b used in the recording process can be used as the laser beam 131 used in the reproduction process. That is, as the laser oscillator 121 used in the reproducing process, the same type or the same laser oscillator as the laser oscillator 101 used in the recording process is used, and the laser oscillator 121 oscillates using the nonlinear optical element 122 as shown in FIG. The laser beam is modulated into harmonics. Further, the stage 112b and the stage 113b may be the same stage as the stage 112a and the stage 113a used in the recording process shown in FIG.

  Specifically, in the recording process shown in FIG. 1, a YAG laser is used as the laser oscillator 101, and a fundamental wave (wavelength: 1064 nm) of the YAG laser is used as the first laser beam 114a and the second laser beam 114b. On the other hand, in the reproduction process shown in FIG. 2, a YAG laser is used as the laser oscillator 121, and the laser light oscillated from the laser oscillator 121 is modulated into a harmonic by the nonlinear optical element 122 to be a laser light 131. As the laser beam 131, for example, a third harmonic (wavelength 355 nm) of a YAG laser is used. In this case, the wavelengths of the first laser beam 114a and the second laser beam 114b used in the recording process with respect to the laser beam 131 used in the reproducing process are tripled, and the pattern formed on the mask original plate 108 is reduced to 1/3 times. The pattern thus formed can be transferred to the resist 130. Note that the laser oscillator is not limited to the YAG laser, and the same kind of laser oscillator may be used as the laser oscillator 101 and the laser oscillator 121, and any of the solid lasers described above can be used.

  Alternatively, the second harmonic (wavelength 532 nm) of the YAG laser may be used as the first laser beam 114a and the second laser beam 114b, and the third harmonic (wavelength 355 nm) of the YAG laser may be used as the laser beam 131. . In this case, the wavelengths of the first laser beam 114a and the second laser beam 114b used in the recording process with respect to the laser beam 131 used in the reproducing process are 1.5 times, and the pattern formed on the mask original plate 108 is 1/1. A pattern reduced by a factor of 5 can be transferred to the resist 130. When harmonics are used as the first laser beam 114a and the second laser beam 114b, the laser beam oscillated from the laser oscillator 101 is divided into the first laser beam 114a and the second laser beam 114b. What is necessary is just to modulate to a harmonic using a nonlinear optical element.

  As described above, the third laser beam 131 is shorter than the first laser beam 114a and the second laser beam 114b, and the harmonics of the first laser beam 114a and the second laser beam 114b are used. Then, a pattern formed by reducing the pattern formed on the mask original plate 108 to an inverse multiple of 0.5 (1 / (0.5 × n), n: an integer of 3 or more) is transferred to the resist 130. Can do. When the laser oscillators 101 and 121 can oscillate laser light from the fundamental wave to the fifth harmonic, the mask master plate 108 is obtained by combining the wavelengths of the laser light oscillated from the laser oscillator 101 and the laser oscillator 121. A pattern obtained by reducing the pattern formed to 1 / 1.5 times, 1/2 times, 1 / 2.5 times, 1/3 times, 1/4 times, or 1/5 times on the resist 130. Is possible.

  For example, when it is desired to form a pattern of 0.5 μm on the resist 130, the pattern of the mask original plate 108 is changed to 1 μm (if the fundamental wave is used for the recording process and the second harmonic is used for the reproducing process, or 2 harmonics when the 4th harmonic is used for the reproduction process), 1.5 μm (when the fundamental wave is used for the recording process and the 3rd harmonic is used for the reproduction process), 2 μm (the fundamental wave is used for the recording process) Used when the fourth harmonic is used in the reproduction process) or 2.5 μm (when the fundamental wave is used in the recording process and the fifth harmonic is used in the reproduction process).

  Further, the exposure method using holography shown in this embodiment mode and an optical system for miniaturizing a pattern may be applied in combination. In this case, the pattern formed on the mask original can be made smaller and transferred to the resist.

  In this embodiment, an example in which a transmission hologram is used has been described. However, a reflection hologram may be used. In the case of using a reflection type hologram, for example, the incident directions of the reference light 110 in the recording process shown in FIG. 1 and the reproduction reference light 127 in the reproduction process shown in FIG. 2 may be reversed. Specifically, in the recording process, the reference beam 110 is incident in a direction different from the direction in which the object beam 109 is irradiated with the hologram recording medium 111 as a boundary (incident from the upper surface side of the hologram recording medium 111 in FIG. 1) for reproduction. In the process, the reproduction reference beam 127 is incident from the opposite direction of the reference beam 110 (incident from the lower surface side of the hologram recording medium 111 in FIG. 2).

  In this way, in the exposure method using holography, it is possible to reduce the mask original pattern and transfer it to the resist by making the wavelength of the laser beam used in the reproduction process shorter than the wavelength of the laser beam used in the recording process. It becomes. Further, by making the laser beam used in the reproduction process a harmonic having a wavelength shorter than that of the laser beam used in the recording process, the pattern formed on the mask original plate is at least n times 0.5 (n is an integer of 3 or more). A pattern reduced to a reciprocal number can be transferred to a resist. As a result, the minimum unit of the numerical value of the pattern formed on the mask original or the pattern formed on the resist can be reduced, and the layout design of the mask original can be simplified. In addition, by reducing the minimum unit of the numerical value of the pattern to be formed on the resist, when manufacturing a device in combination with an exposure process using holography and another exposure process (stepper, MPA), alignment and the like can be accurately performed. It can be carried out. The present invention becomes more effective as the number of processes and device miniaturization progress.

(Embodiment 2)
In this embodiment mode, an exposure method different from that of the above embodiment mode will be described with reference to drawings. Specifically, an exposure method using total reflection holography using a prism will be described.

  First, FIG. 3 shows an example of an exposure apparatus used in a process (recording process) of recording a mask original pattern on a hologram recording medium.

  The exposure apparatus shown in FIG. 3 includes a laser oscillator 101, a beam splitter 102 that divides the laser light oscillated from the laser oscillator 101, mirrors 103, 125a, and 126a that reflect the laser light in a desired direction, Enlargement optical systems 104 and 105 for enlarging the scale and stages 112a and 113a are provided.

  The stage 112a and the stage 113a are provided in order to place a sample used for exposure, and the position can be adjusted in the vertical direction and the horizontal direction. Here, an example is shown in which a mask original 108 provided on a substrate 107 is arranged on a stage 112a as a sample, and a hologram recording medium 111 mounted on a prism 132 is arranged on a stage 113a.

  Next, a process (recording process) of recording the pattern of the mask original 108 on the hologram recording medium 111 mounted on the prism 132 using the exposure apparatus shown in FIG. 3 will be described.

  The laser light oscillated from the laser oscillator 101 is split into laser light having an appropriate intensity ratio by the beam splitter 102. Here, the light is divided into a first laser beam 114a and a second laser beam 114b. Thereafter, the scale of the first laser beam 114 a is enlarged by the magnifying optical system 105, and then enters the hologram recording medium 111 as the object beam 109 through the mask original plate 108 formed on the substrate 107. On the other hand, the scale of the second laser beam 114b is magnified by the magnifying optical system 104 and the traveling direction is changed by the mirrors 125a and 126a, and then enters the hologram recording medium 111 as the reference beam 110. Here, the reference light 110 is totally reflected at the boundary surface between the hologram recording medium 111 and the air via the prism 132.

  As described above, when the object light 109 and the reference light 110 are simultaneously irradiated onto the hologram recording medium 111, interference fringes are formed on the hologram recording medium 111. That is, the hologram having the pattern of the mask original plate 108 is recorded on the hologram recording medium 111.

As the laser oscillator 101, a solid-state laser such as YAG laser, YVO ₄ laser, YLF laser, YAlO ₃ laser, GdVO ₄ laser, or the like can be used. Specifically, a solid-state laser using a crystal in which Cr, Nd, Er, Ho, Ce, Co, Ti, or Tm is doped in a crystal such as YAG, YVO ₄ , YLF, YAlO ₃ , GdVO ₄ or the like is used. In the present invention, the fundamental wave to the fifth harmonic of these solid-state laser oscillators are selectively applied according to use. The harmonic with respect to the fundamental wave can be obtained by using a nonlinear optical element.

  Next, FIG. 4 shows an example of a process (reproduction process) in which the hologram recorded on the hologram recording medium 111 formed in FIG. 3 is transferred to a resist and reproduced.

  Laser light oscillated from the laser oscillator 121 is modulated into harmonics by the nonlinear optical element 122 to become laser light 131. Thereafter, the traveling direction of the laser beam 131 is changed by the mirror 123, and then the scale of the laser beam 131 is expanded by the magnifying optical system 124. Then, after the traveling direction is changed by the mirrors 125 b and 126 b, the reproduction reference light 127 enters the hologram recording medium 111 via the prism 132. The reproduction reference light 127 incident on the hologram recording medium 111 is diffracted by the interference fringes formed on the hologram recording medium 111, and a part of the reproduction reference light 127 is incident on the resist 130 provided on the substrate 129. Note that the magnifying optical system 124 and the mirrors 125b and 126b shown in FIG. 4 can be the same as the magnifying optical system 104 and the mirrors 125a and 126a shown in FIG. 3, respectively.

  Here, the substrate 129 is disposed on the stage 112b, and the hologram recording medium 111 on which interference fringes are formed is disposed on the stage 113b. The reproduction reference beam 127 is incident on the hologram recording medium 111 from the opposite direction to the reference beam 110 shown in FIG. 3 via the prism 132, and the resist 130 is located at the position where the mask original plate 108 shown in FIG. Has been placed.

  In the reproduction step shown in FIG. 4, the first laser beam 114a used in the recording step shown in FIG. 3 and the laser beam 131 used when transferring the hologram recorded on the hologram recording medium 111 to the resist 130, and The wavelength is shorter than that of the second laser beam 114b, and the wavelength is the inverse of 0.5 times the wavelength of the first laser beam 114a and the second laser beam 114b (n is an integer of 3 or more). Use laser light. For example, as the laser beam 131 used in the reproduction process, the harmonics of the first laser beam 114a and the second laser beam 114b used in the recording process can be used. That is, as the laser oscillator 121 used in the reproducing process, the same type or the same laser oscillator as the laser oscillator 101 used in the recording process is used, and the laser oscillator 121 oscillates using the nonlinear optical element 122 as shown in FIG. The laser beam is modulated into harmonics. Further, the stage 112b and the stage 113b may be the same stage as the stage 112a and the stage 113a used in the recording process shown in FIG.

For example, in the recording process shown in FIG. 3, using a YVO ₄ laser as the laser oscillator 101, YVO ₄ laser fundamental wave (wavelength 1064 nm) is used as the first laser beam 114a and the second laser beam 114b. On the other hand, in the reproduction process shown in FIG. 4, using a YVO ₄ laser as the laser oscillator 121, YVO ₄ laser fourth harmonic (wavelength 266 nm) is used as the laser beam 131. In this case, the wavelength of the first laser beam 114a and the second laser beam 114b used in the recording process with respect to the laser beam 131 used in the reproducing process is quadrupled, and the pattern formed on the mask original plate 108 is reduced to ¼. The pattern thus formed can be transferred to the resist 130. The laser oscillator is not limited to the YVO ₄ laser, and the same type of laser oscillator may be used as the laser oscillator 101 and the laser oscillator 121, and any of the solid lasers described above can be used.

Further, YVO ₄ laser second harmonic (wavelength 532 nm) is used as the first laser beam 114a and the second laser beam 114b, with YVO ₄ laser fourth harmonic (wavelength 266 nm) as the laser beam 131 Also good. In this case, the wavelengths of the first laser beam 114a and the second laser beam 114b used in the recording process with respect to the laser beam 131 used in the reproduction process are doubled, and the pattern formed on the mask original plate 108 is reduced to 1/2 times. The pattern thus formed can be transferred to the resist 130.

  As described above, the third laser beam 131 is shorter than the first laser beam 114a and the second laser beam 114b, and the harmonics of the first laser beam 114a and the second laser beam 114b are used. Thus, a pattern obtained by reducing the pattern formed on the mask original plate 108 to a reciprocal multiple of 0.5 (n is an integer of 3 or more) can be transferred to the resist 130. When the laser oscillators 101 and 121 can oscillate laser light from the fundamental wave to the fifth harmonic, the mask master plate 108 is obtained by combining the wavelengths of the laser light oscillated from the laser oscillator 101 and the laser oscillator 121. A pattern obtained by reducing the pattern formed to 1 / 1.5 times, 1/2 times, 1 / 2.5 times, 1/3 times, 1/4 times, or 1/5 times on the resist 130. Is possible.

  For example, when it is desired to form a pattern of 1 μm on the resist 130, the pattern of the mask original plate 108 is 2 μm (when the fundamental wave is used for the recording process and the second harmonic is used for the reproduction process, or the second harmonic is used for the recording process. When using the fourth harmonic in the reproduction process using waves), 3 μm (when using the fundamental wave in the recording process and using the third harmonic in the reproduction process), 4 μm (using the fundamental wave in the recording process) (When using the fourth harmonic) or 5 μm (when using the fundamental wave for the recording process and using the fifth harmonic for the reproduction process).

  In this way, in the exposure method using holography, by making the wavelength of the laser beam used in the reproduction process shorter than the wavelength of the laser beam used in the recording process, it is possible to reduce the mask pattern and expose the resist to the resist. It becomes. Further, by making the laser beam used in the reproduction process a harmonic having a wavelength shorter than that of the laser beam used in the recording process, the pattern formed on the mask original plate is at least n times 0.5 (n is an integer of 3 or more). A pattern reduced to a reciprocal number can be transferred to a resist. As a result, the minimum unit of the numerical value of the pattern formed on the mask original or the pattern formed on the resist can be reduced, and the layout design of the mask original can be simplified. In addition, by making the minimum unit of the pattern to be formed on the resist small, alignment and the like are accurately performed when manufacturing a device in combination with an exposure process using holography and another exposure process (stepper, MPA). Can do. The present invention becomes more effective as the number of processes and device miniaturization progress.

(Embodiment 3)
In this embodiment mode, an exposure method different from that of the above embodiment mode will be described with reference to drawings. Specifically, in the exposure method using holography, a case where a recording process and a reproduction process are performed using the same laser oscillator and exposure apparatus will be described.

  First, an example of an exposure apparatus used in this embodiment is shown in FIG.

  The exposure apparatus shown in FIG. 5 includes a laser oscillator 101, a nonlinear optical element 122a that modulates laser light oscillated from the laser oscillator 101 into harmonics, beam splitters 102 and 133 that divide the laser light, and a desired laser light. Mirrors 103, 106, 126, 134, 135 that reflect in the direction of, magnification optical systems 104, 105 that expand the scale of the laser light, stages 112, 113, and shutters 141 a-141 c that block the laser light ing.

  The stage 112 and the stage 113 are provided in order to place a sample used for exposure, and the position can be adjusted in the vertical direction and the horizontal direction. Here, an example in which a mask original 108 formed on a substrate 107 is arranged on a stage 112 and a hologram recording medium 111 is arranged on a stage 113 is shown as a sample.

  The shutters 141a to 141c are provided with a material capable of blocking laser light, and the laser light can be selectively blocked by opening and closing the shutters 141a to 141c.

  Next, a process (recording process) for recording the pattern of the mask original plate 108 on the hologram recording medium 111 will be described.

  The laser light oscillated from the laser oscillator 101 is modulated into a harmonic by the nonlinear optical element 122a to become a laser light 142. Next, the laser beam 142 is divided into laser beams having an appropriate intensity ratio by the beam splitter 102. Here, it is divided into a first laser beam 142a and a second laser beam 142b. In the recording process, when a fundamental wave is used, laser light is incident on the beam splitter 102 without passing through the nonlinear optical element 122a.

  Then, the scale of the first laser beam 142a is subsequently magnified by the magnifying optical system 105, and then enters the hologram recording medium 111 as the object beam 109 through the mask original 108 formed on the substrate 107. On the other hand, the scale of the second laser beam 142b is expanded by the magnifying optical system 104, and thereafter, the beam is split into the third laser beam 142c and the fourth laser beam 142d by the beam splitter 133. The third laser beam 142 c is incident on the hologram recording medium 111 as the reference beam 110 after the traveling direction is changed by the mirror 106. The fourth laser beam 142d is blocked by the shutter 141c after the traveling direction is changed by the mirrors 134 and 126. In the present embodiment, the beam splitter 133 may be a mirror, and can be configured to move during the recording process so as not to obstruct the optical path.

  In this way, the hologram recording medium 111 is simultaneously irradiated with the object light 109 and the reference light 110, whereby interference fringes between the object light 109 and the reference light 110 are formed on the hologram recording medium 111. That is, the hologram having the pattern of the mask original plate 108 is recorded on the hologram recording medium 111.

  In the recording process, the shutters 141a and 141b are in an open state (a state in which laser light is not blocked), and a shutter 141c is in a closed state (a state in which laser light is blocked).

  Next, FIG. 6 shows an example of a process (reproduction process) in which the hologram recorded on the hologram recording medium 111 formed in FIG. 5 is transferred to a resist and reproduced.

  The laser light oscillated from the laser oscillator 101 used in the recording process shown in FIG. 5 is modulated into a harmonic by the nonlinear optical element 122b to become a laser light 143. The laser beam 143 is modulated into a harmonic so that the wavelength is shorter than that of the laser beam 142 used in the recording process. Next, the laser beam 143 is divided into laser beams having an appropriate intensity ratio by the beam splitter 102. Here, it is divided into a fifth laser beam 143a and a sixth laser beam 143b.

  Then, the fifth laser beam 143a is blocked by the shutter 141a. The sixth laser beam 143b is divided into the seventh laser beam 143c and the eighth laser beam 143d by the beam splitter 133 after the scale of the sixth laser beam 143b is expanded by the expansion optical system 104. . The seventh laser beam 143c is blocked by the shutter 141b. The eighth laser beam 143d is incident on the hologram recording medium 111 as the reproduction reference beam 127 after the traveling direction is changed by the mirrors 134, 126, and 135. The reproduction reference light 127 incident on the hologram recording medium 111 is diffracted by the interference fringes formed on the hologram recording medium 111, and a part of the reproduction reference light 127 is incident on the resist 130 provided on the substrate 129. Here, a resist 130 is arranged on the stage 112, and a hologram recording medium 111 on which interference fringes are formed is arranged on the stage 113. The reproduction reference beam 127 is incident on the hologram recording medium 111 from the opposite direction to the reference beam 110 shown in FIG. 5, and the resist 130 is arranged at the position where the mask original plate 108 shown in FIG.

  In the reproduction process, the shutters 141a and 141b are in a closed state (a state in which laser light is blocked), and a shutter 141c is in an open state (a state in which laser light is not blocked).

  As described above, by providing the shutters 141a to 141c, in the exposure method using holography, the recording process and the reproduction process can be performed using the same laser oscillator and exposure apparatus.

  Note that this embodiment can be freely combined with the above embodiment. For example, instead of the exposure method shown in the present embodiment, total reflection holography may be used.

(Embodiment 4)
In the present invention, exposure may be performed using a Fourier transform hologram instead of the exposure method described in the above embodiment. In the case of performing exposure using a Fourier transform hologram, the laser light oscillated from the laser oscillator is divided into a first laser light and a second laser light, and then the first laser light is passed through a mask original to a hologram recording medium. At the same time as the incidence of object light, the second laser light is incident on the hologram recording medium as reference light to form a hologram. At this time, a Fourier transform lens is provided between the mask original and the hologram recording medium, and the laser light that has passed through the mask original enters the hologram recording medium through the Fourier transform lens.

  By performing exposure using a Fourier transform hologram, the resolution of the reproduced image can be increased. Note that the laser light used in the recording process and the laser light used in the reproducing process have a wavelength shorter than that of the laser light used in the recording process, as shown in the above embodiment, and in the recording process. The wavelength of the laser beam used is set to n times 0.5 (n is an integer of 3 or more) of the wavelength of the laser beam used in the reproduction process. Alternatively, the laser oscillator used in the recording process and the laser oscillator used in the reproducing process are of the same type, the laser light used in the reproducing process is made shorter in wavelength than the laser light used in the recording process, and the laser light used in the reproducing process Harmonics can be used.

  In the present invention, the hologram applied in the exposure method using holography may be either an amplitude hologram or a phase hologram. When a phase hologram is applied, there is an advantage that diffraction efficiency is high. Moreover, diffraction efficiency can be improved by forming a thick hologram.

  Note that this embodiment can be freely combined with the above embodiment.

(Embodiment 5)
In this embodiment, a method for manufacturing a semiconductor device using the exposure method described in the above embodiment will be described with reference to drawings. Note that in this embodiment, a static random access memory (SRAM) cell having six transistors is described as an example, but the present invention is not limited to this.

  The SRAM shown in this embodiment includes inverters 301 and 302, and inputs of the inverters 301 and 302 are connected to bit lines BL1 and BL2 via switches S1 and S2, respectively (FIG. 7). ). The switches S1 and S2 are controlled by a row selection signal transmitted through the word line WL. Each inverter 301, 302 is powered by a high voltage VDD and a low voltage GND which is generally grounded. In order to write information in the memory cell, the voltage VDD is applied to one of the bit lines BL1 and BL2, and the voltage GND is applied to the other of the bit lines.

  Inverter 301 includes an n-channel transistor N1 and a p-channel transistor P1 connected in series. The source of the p-channel transistor P1 is connected to the voltage VDD, and the source of the n-channel transistor N1 is connected to the voltage GND. The drain of the p-channel transistor P1 and the drain of the n-channel transistor N1 are connected, and the gate of the p-channel transistor P1 and the gate of the n-channel transistor N1 are connected. Similarly, the inverter 302 includes a p-channel transistor P2 and an n-channel transistor N2 connected in series like a p-channel transistor P1 and an n-channel transistor N1, and the p-channel transistor P2 and the n-channel transistor N2 are connected. The drain of N2 is connected, and the gate of the transistor P2 and the gate of the n-channel type N2 are connected.

  In the operation of the SRAM shown in FIG. 7, the switches S1 and S2 are turned on, and the input and output states of the inverters 301 and 302 are set. Next, the switches S1 and S2 are turned off, and the signal states in the inverters 301 and 302 are maintained. In order to read information from the memory cell, each bit line BL1, BL2 is precharged to a voltage range between the voltages VDD and GND. The switches S1 and S2 are turned on, and the voltage on the bit line changes based on the signal state of the inverters 301 and 302. Data stored in the memory cell is read by the sense amplifier connected to the bit line.

  An example of the circuit arrangement of the SRAM shown in FIG. 7 is shown in FIG. FIG. 8 shows an SRAM formed of a semiconductor film and two wiring layers including a gate wiring layer. When the semiconductor film 408b in which the n-channel transistor is formed and the semiconductor film 408a in which the p-channel transistor is formed are disposed in the lower layer, the first wiring layers 456 and 458 are disposed on the upper layer via an insulating film. 460 is arranged. The first wiring layer 456 is a layer for forming a gate electrode, and an n-channel transistor N1 and a p-channel transistor P1 are formed crossing the semiconductor films 408b and 408a. The first wiring layer 458 is a layer for forming a gate electrode, and an n-channel transistor N2 and a p-channel transistor P2 are formed crossing the semiconductor films 408b and 408a. The first wiring layer 460 is a word line (WL), and switches S1 and S2 are formed crossing the semiconductor film 408b. The first wiring layers 456, 458, and 460 have such a relationship with the semiconductor films 408b and 408a, and form gate electrodes.

  The second wiring layers 462, 432b, 432c, and 464 are formed with the first wiring layers 456, 458, and 460 through an insulating layer. The second wiring layer 462 forms a bit line (BL1), the second wiring layer 464 forms a bit line (BL2), the second wiring layer 432b forms a power supply line (VDD), and the second wiring layer 432c forms a ground potential line (GND). is doing.

  The contact hole C1 is an opening formed in the insulating layer and connects the second wiring layer 462 and the semiconductor film 408b. The contact hole C2 is an opening formed in the insulating layer, and connects the second wiring layer 464 and the semiconductor film 408a. The contact hole C3 is an opening formed in the insulating layer, and connects the second wiring layer 432a and the semiconductor film 408b. The contact hole C4 is an opening formed in the insulating layer and connects the second wiring layer 432a and the semiconductor film 408a. The contact hole C5 is an opening formed in the insulating layer, and connects the second wiring layer 432d and the semiconductor film 408b. The contact hole C6 is an opening formed in the insulating layer, and connects the second wiring layer 432d and the semiconductor film 408a. The contact hole C7 is an opening formed in the insulating layer, and connects the second wiring layer 432b and the semiconductor film 408b. The contact hole C8 is an opening formed in the insulating layer, and connects the second wiring layer 432c and the semiconductor film 408a. The contact hole C9 is an opening formed in the insulating layer, and connects the second wiring layer 432a and the first wiring layer 458. The contact hole C10 is an opening formed in the insulating layer, and connects the second wiring layer 432d and the first wiring layer 456. In this way, the SRAM shown in FIG. 8 is formed by the contact holes C1 to C10 connecting the semiconductor film and the first wiring layer and the second wiring layer.

  Next, a manufacturing process of such an SRAM will be described with reference to FIG. 9 which is a cross-sectional view corresponding to the line AB (p-channel transistor P1 and n-channel transistor N2) shown in FIG.

  First, the semiconductor film 403 is formed over the substrate 401 with the insulating film 402 functioning as a base film, and the resist 404 is formed over the semiconductor film 403 (FIG. 9A).

  The substrate 401 is selected from a glass substrate, a quartz substrate, a metal substrate (for example, a ceramic substrate or a stainless steel substrate), and a semiconductor substrate such as a Si substrate. In addition, a substrate such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), or acrylic can be selected as the plastic substrate.

  The insulating film 402 is formed using silicon oxide, silicon nitride, silicon oxynitride (SiOxNy) (x> y> 0), silicon nitride oxide (SiNxOy) (x> y> 0), or the like using a CVD method, a sputtering method, or the like. It is formed using an insulating material. For example, in the case where the insulating film 402 has a two-layer structure, a silicon nitride oxide film may be formed as the first insulating film and a silicon oxynitride film may be formed as the second insulating film. Alternatively, a silicon nitride film may be formed as the first insulating film, and a silicon oxide film may be formed as the second insulating film. In this manner, by forming the insulating film 402 functioning as a blocking layer, alkali metal such as Na or alkaline earth metal from the substrate 401 can be prevented from adversely affecting the element formed thereon. Note that the insulating film 402 may be omitted when quartz is used for the substrate 401.

  The semiconductor film 403 is preferably formed using a crystalline semiconductor film. The crystalline semiconductor film is obtained by crystallizing an amorphous semiconductor film formed over the insulating film 402 by heat treatment or laser light irradiation, or after amorphizing the crystalline semiconductor film formed over the insulating film 402. , Recrystallized materials, and the like.

When crystallization or recrystallization is performed by laser light irradiation, an LD-excited continuous wave (CW) laser (YVO ₄ , second harmonic (wavelength 532 nm)) can be used as a laser light source. The second harmonic is not particularly limited to the second harmonic, but the second harmonic is superior to higher harmonics in terms of energy efficiency. When the semiconductor film is irradiated with the CW laser, energy is continuously given to the semiconductor film. Therefore, once the semiconductor film is in a molten state, the molten state can be continued. Furthermore, the solid-liquid interface of the semiconductor film can be moved by scanning with a CW laser, and crystal grains that are long in one direction can be formed along the direction of this movement. The solid laser is used because the output stability is higher than that of a gas laser or the like, and stable processing is expected. Note that not only the CW laser but also a pulse laser having a repetition frequency of 10 MHz or more can be used. If a pulse laser with a high repetition frequency is used, the semiconductor film can always remain in a molten state if the laser pulse interval is shorter than the time from when the semiconductor film melts until it solidifies. A semiconductor film including crystal grains that are long in one direction can be formed. Other CW lasers and pulse lasers with a repetition frequency of 10 MHz or more can also be used. For example, examples of the gas laser include an Ar laser, a Kr laser, and a CO ₂ laser. Examples of the solid-state laser include a YAG laser, a YLF laser, a YAlO ₃ laser, a GdVO ₄ laser, a KGW laser, a KYW laser, an alexandrite laser, a Ti: sapphire laser, a Y ₂ O ₃ laser, and a YVO ₄ laser. Further, as a special type of solid-state laser, there are ceramic lasers such as a YAG laser, a Y ₂ O ₃ laser, a GdVO ₄ laser, and a YVO ₄ laser. Examples of the metal vapor laser include a helium cadmium laser. In addition, it is preferable to emit laser light in TEM ₀₀ (single transverse mode) in a laser oscillator because energy uniformity of a linear beam spot obtained on the irradiated surface can be improved. In addition, a pulsed excimer laser may be used.

  As the resist 404, a composition containing a photosensitive agent may be used. Both a negative type (a photoresist in which an exposed portion remains as a pattern after development) and a positive type (a photoresist in which an unexposed portion remains as a pattern after development) are used. Is possible. In the present embodiment, a case where a negative resist is used is shown.

  Next, the resist 404 is selectively removed by exposing and etching the resist 404 through a mask provided with a metal 406 that selectively blocks light on the light-transmitting film 405. A resist pattern is formed. Then, the semiconductor film 403 not covered with the resist pattern is selectively removed, so that an island-shaped semiconductor film is formed (FIG. 9B). Here, resists 407a and 407b are formed by selectively removing the resist 404, and island-shaped semiconductor films 408a and 408b are formed by selectively removing the semiconductor film 403 not covered with the resists 407a and 407b. The example which formed is shown. Here, the resist 404 is exposed using an exposure method such as a stepper or MPA.

  Next, a conductive film 410 is formed through the gate insulating film 409 so as to cover the island-shaped semiconductor films 408a and 408b, and a resist 411 is formed over the conductive film 410 (FIG. 9C).

As the gate insulating film 409, silicon oxide, silicon nitride, silicon oxynitride (SiOxNy) (x>y> 0), silicon nitride oxide (SiNxOy) (x>y> 0), or the like is used. Such an insulating layer is formed by a vapor deposition method or a sputtering method. Further, the semiconductor films 408a and 408b are formed in an oxygen atmosphere (for example, an atmosphere of oxygen (O ₂ ) and a rare gas (including at least one of He, Ne, Ar, Kr, and Xe) or oxygen and hydrogen (H ₂ ). And a rare gas atmosphere) or a nitrogen atmosphere (for example, a nitrogen (N ₂ ) and rare gas (including at least one of He, Ne, Ar, Kr, and Xe) atmosphere, or a nitrogen, hydrogen, and rare gas atmosphere Alternatively, the gate insulating film 409 can be formed by subjecting the surfaces of the semiconductor films 408a and 408b to oxidation treatment or nitridation treatment with high-density plasma treatment under a rare gas atmosphere with NH ₃ . By forming the gate insulating film 409 by performing oxidation treatment or nitridation treatment on the surfaces of the semiconductor films 408a and 408b by high-density plasma treatment, the density of defect states serving as traps for electrons and holes can be reduced.

  The conductive film 410 is formed using other refractory metal such as tungsten, molybdenum, titanium, tantalum, chromium, niobium, or the like. Alternatively, an alloy of the above-described metal such as an alloy of molybdenum and tungsten, titanium nitride, or tungsten nitride, or a conductive metal nitride or conductive oxide may be used. And it can form with the laminated structure of a tantalum nitride and tungsten. Alternatively, polysilicon doped with an impurity element such as phosphorus may be used.

  Next, by using the hologram recording medium 412 on which the hologram is formed, the resist 411 is exposed and then etched to selectively remove the resist 411 and form a resist pattern. Then, the conductive film 410 which is not covered with the resist pattern is selectively removed, so that a conductive film to be a gate electrode is formed (FIG. 10A). Here, resists 413a and 413b are formed by selectively removing the resist 411, and gate electrodes 414a and 414b are formed by selectively removing the conductive film 410 not covered with the resists 413a and 413b. An example is shown.

  Note that the resists 413 a and 413 b used for forming the conductive films to be the gate electrodes 414 a and 414 b in FIG. 10A are formed by using an exposure method using holography for the resist 411. Specifically, an interference fringe is formed on the hologram recording medium 412 using any of the recording steps shown in the above embodiment, and a laser is applied to the resist 411 via the hologram recording medium 412 on which the interference fringe is formed. Exposure is performed by irradiating light. Note that the laser light used to irradiate the resist 411 uses harmonics of laser light used in a recording process for forming interference fringes on the hologram recording medium 412.

  By reduction exposure using holography, the gate electrode can be formed with a pattern smaller than the mask original. As a result, the patterns of the semiconductor films 408a and 408b can be formed more finely, and the degree of integration can be improved.

  Next, using the gate electrodes 414a and 414b and the resists 413a and 413b or the gate electrodes 414a and 414b as masks, an impurity element imparting N-type conductivity is added to the semiconductor films 408a and 408b at a low concentration, and the low-concentration impurity regions 415 are added. Form. After that, a resist 416 is selectively formed over the semiconductor film 408b and the gate electrode 414b, and a high-concentration impurity element imparting p-type conductivity is selectively added to the semiconductor film 408a using the gate electrode 414a as a mask (FIG. 10). (B)). Through this step, a channel region is formed in the region of the semiconductor film 408a located below the gate electrode 414a, and a P-type high-concentration impurity region 417 serving as a source region or a drain region is formed in other regions.

  Next, after the resist 416 is removed, an insulating film is formed so as to cover the gate insulating film 409, the gate electrode 414a, and the gate electrode 414b. The insulating film is formed by a single layer or a stack of layers including an inorganic material of silicon, silicon oxide, or silicon nitride, or a layer including an organic material such as an organic resin, by a CVD method, a sputtering method, or the like. . Next, the insulating layer is selectively etched by anisotropic etching mainly in the vertical direction, so that an insulating layer (also referred to as a sidewall) 418 in contact with the side surfaces of the gate electrode 414a and the gate electrode 414b is formed. After that, a resist 419 is selectively formed above the semiconductor film 408a and the gate electrode 414a, and a high concentration that imparts N-type to the semiconductor film 408b using the insulating film 418 in contact with the side surfaces of the gate electrode 414b and the gate electrode 414b as a mask. An impurity element is selectively added (FIG. 10C). Through this step, a channel region is formed in the region of the semiconductor film 408b located below the gate electrode 414b, and a low-concentration impurity region (also referred to as an LDD region) indicating N-type in the region of the semiconductor film 408b located below the insulating film 418. N-type high concentration impurity region 420 to be a source region or a drain region is formed in other regions.

  Next, an insulating film is formed so as to cover the semiconductor films 408a and 408b and the gate electrodes 414a and 414b, and then a resist is formed over the insulating film (FIG. 11A). Here, a case is shown in which a resist 423 is formed over the insulating film 422 after the insulating film 421 and the insulating film 422 are stacked as the insulating film.

  As the insulating films 421 and 422, silicon oxide, silicon oxynitride (SiOxNy) (x> y> 0), silicon nitride oxide (SiNxOy) (x> y> 0), or the like formed by a CVD method, a sputtering method, or the like is used. be able to. Alternatively, a single layer or a stacked structure including an organic material such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, acrylic, or epoxy, a siloxane material such as a siloxane resin, or an oxazole resin can be used. Note that the siloxane material corresponds to a material including a Si—O—Si bond. Siloxane has a skeleton structure formed of a bond of silicon (Si) and oxygen (O). As a substituent, an organic group containing at least hydrogen (for example, an alkyl group or an aromatic hydrocarbon) is used. A fluoro group can also be used as a substituent. Alternatively, an organic group containing at least hydrogen and a fluoro group may be used as a substituent. The oxazole resin is, for example, photosensitive polybenzoxazole. Photosensitive polybenzoxazole has a low dielectric constant (dielectric constant 2.9 at room temperature of 1 MHz) and high heat resistance (differential thermal analysis (TGA) thermal decomposition temperature 550 ° C. at a temperature increase of 5 ° C./min). The material has a low water absorption rate (0.3% at room temperature for 24 hours). Oxazole resin has a low relative dielectric constant (about 2.9) compared to the relative dielectric constant (about 3.2 to 3.4) of polyimide, etc., so that the generation of parasitic capacitance is suppressed and high speed operation is performed. Can do. Here, as the insulating film 421, silicon oxide, silicon oxynitride (SiOxNy) (x> y> 0) or silicon nitride oxide (SiNxOy) (x> y> 0) formed by a CVD method is formed, and the insulating film 422 is formed. As an organic material such as polyimide, polyamide, polyvinylphenol, benzocyclobutene, acrylic, or epoxy, a siloxane material such as a siloxane resin, or an oxazole resin.

  Next, using the hologram recording medium 424 on which the hologram is formed, the resist 423 is exposed and then etched, whereby the resist 423 is selectively removed to form a resist pattern. Then, the insulating films 421 and 422 not covered with the resist pattern are selectively removed to expose the semiconductor films 408a and 408b (FIG. 11B). Here, resists 425a to 425e are formed by selectively removing the resist 423, and contact holes 426a to 426d are formed by selectively removing the insulating films 421 and 422 not covered with the resists 425a to 425e. The example which formed is shown.

  A contact hole having a smaller diameter than the mask original plate can be formed by reduction exposure using a hologram. As a result, the area in which the semiconductor films 408a and 408b and the conductive films 431a to 431d form contacts can be reduced. Accordingly, the interval between the contact holes 426a to 426d can be narrowed, and the degree of integration can be improved.

  Next, a conductive film 427 is formed so as to fill at least the contact holes 426a to 426d, and a resist 428 is formed over the conductive film 427 (FIG. 11C).

  The conductive film 427 can have a single-layer structure or a stacked structure formed using one kind of element selected from aluminum, tungsten, titanium, tantalum, molybdenum, nickel, and neodymium (Nd) or an alloy containing a plurality of such elements. For example, the conductive film formed using an alloy containing a plurality of the elements can be formed using an aluminum alloy containing titanium, an aluminum alloy containing neodymium, or the like. In the case of providing a stacked structure, for example, an aluminum layer or an aluminum alloy layer as described above may be stacked between titanium layers. Here, the conductive film 431b forms a power supply line (VDD), and the conductive film 431c forms a ground potential line (GND).

  Next, by using the hologram recording medium 429 on which the hologram is formed, the resist 428 is exposed and then etched to selectively remove the resist 428 and form a resist pattern. Then, the conductive film 427 that is not covered with the resist pattern is selectively removed, so that a conductive film to be a source electrode or a drain electrode is formed (FIG. 12A). Here, the resist 428 is selectively removed to form resists 430a to 430d, and the conductive film 427 that is not covered with the resists 430a to 430d is selectively removed to be a conductive film that becomes a source electrode or a drain electrode. An example in which films 431a to 431d are formed is shown.

  A contact hole having a smaller diameter than the mask original plate can be formed by reduced exposure using holography. As a result, the area in which the semiconductor films 408a and 408b and the conductive films 431a to 431d form contacts can be reduced. Accordingly, the interval between the contact holes 426a to 426d can be narrowed, and the degree of integration can be improved.

  Then, the resists 430a to 430d are removed. Then, a transistor can be formed (FIG. 12B). As described above, in the manufacturing process of the semiconductor device, by applying the exposure method using the holography described in the first to fourth embodiments, even when a different exposure method is used, a fine pattern is formed. In addition, alignment can be performed with high accuracy.

  In this embodiment mode, an exposure method using holography is applied when forming a gate electrode, a contact hole, or a source electrode or a drain electrode. However, the present invention is not limited to this, and an island-shaped semiconductor is used. An exposure method using holography may be applied in all steps such as a film formation step, or an exposure method using holography may be applied only to the step of forming a gate electrode. That is, in the manufacturing process of a semiconductor device, an exposure method using holography may be applied in at least one step.

  Note that this embodiment can be freely combined with the above embodiment.

(Embodiment 6)
In this embodiment, an example of usage of a semiconductor device obtained using the manufacturing method described in Embodiment 5 will be described. Specifically, application examples of a semiconductor device capable of inputting and outputting data without contact will be described below with reference to the drawings. A semiconductor device in which data can be input / output without contact is also referred to as an RFID tag, an ID tag, an IC tag, an IC chip, an RF tag, a wireless tag, an electronic tag, or a wireless chip depending on the application.

  The semiconductor device 80 has a function of communicating data without contact, and controls the high frequency circuit 81, the power supply circuit 82, the reset circuit 83, the clock generation circuit 84, the data demodulation circuit 85, the data modulation circuit 86, and other circuits. A control circuit 87, a memory circuit 88, and an antenna 89 are provided (FIG. 13A). The high frequency circuit 81 is a circuit that receives a signal from the antenna 89 and outputs the signal received from the data modulation circuit 86 to the antenna 89, and the power supply circuit 82 is a circuit that generates a power supply potential from the received signal, and a reset circuit 83. Is a circuit that generates a reset signal, a clock generation circuit 84 is a circuit that generates various clock signals based on a reception signal input from an antenna 89, and a data demodulation circuit 85 demodulates the reception signal to control a control circuit 87. The data modulation circuit 86 is a circuit that modulates the signal received from the control circuit 87. Further, as the control circuit 87, for example, a code extraction circuit 91, a code determination circuit 92, a CRC determination circuit 93, and an output unit circuit 94 are provided. The code extraction circuit 91 is a circuit that extracts a plurality of codes included in an instruction sent to the control circuit 87, and the code determination circuit 92 compares the extracted code with a code corresponding to a reference. The CRC determination circuit 93 is a circuit that detects the presence or absence of a transmission error or the like based on the determined code.

  In FIG. 13A, in addition to the control circuit 87, a high frequency circuit 81 and a power supply circuit 82 which are analog circuits are included. Even such a circuit can be formed by an exposure method using holography as described in the above embodiment. By using such an exposure method, the size of the transistor can be reduced. Therefore, the chip size can be reduced even when the glass substrate has low flatness.

  Next, an example of operation of the above-described semiconductor device will be described. First, a radio signal is received by the antenna 89. The radio signal is sent to the power supply circuit 82 via the high frequency circuit 81, and a high power supply potential (hereinafter referred to as VDD) is generated. VDD is supplied to each circuit included in the semiconductor device 80. The signal sent to the data demodulation circuit 85 via the high frequency circuit 81 is demodulated (hereinafter, demodulated signal). Further, a signal (reset signal) that has passed through the reset circuit 83, a signal (clock signal) that has passed through the clock generation circuit 84, and a demodulated signal are sent to the control circuit 87 via the high-frequency circuit 81. The signal sent to the control circuit 87 is analyzed by the code extraction circuit 91, the code determination circuit 92, the CRC determination circuit 93, and the like. Then, information on the semiconductor device stored in the memory circuit 88 is output in accordance with the analyzed signal. The output semiconductor device information is encoded through the output unit circuit 94. Further, the encoded information of the semiconductor device 80 is modulated by the data modulation circuit 86 and transmitted by the antenna 89 on a radio signal. Note that in a plurality of circuits included in the semiconductor device 80, a low power supply potential (hereinafter referred to as VSS) is common and VSS can be GND.

  As described above, by transmitting a signal from the reader / writer to the semiconductor device 80 and receiving the signal transmitted from the semiconductor device 80 by the reader / writer, the data of the semiconductor device can be read.

  Further, the semiconductor device 80 may be of a type in which power supply voltage is supplied to each circuit by electromagnetic waves without mounting a power source (battery), or each circuit is mounted by using electromagnetic waves and a power source (battery). The power supply voltage may be supplied to the type.

  Next, an example of a usage pattern of a semiconductor device capable of inputting and outputting data without contact will be described. A reader / writer 3200 is provided on a side surface of the portable terminal including the display portion 3210, and a semiconductor device 3230 is provided on a side surface of the article 3220 (FIG. 13B). When the reader / writer 3200 is held over the semiconductor device 3230 included in the product 3220, information about the product such as the description of the product, such as the raw material and origin of the product, the inspection result for each production process and the history of the distribution process, is displayed on the display unit 3210. Is done. Further, when the product 3260 is conveyed by a belt conveyor, the product 3260 can be inspected using the reader / writer 3240 and the semiconductor device 3250 provided in the product 3260 (FIG. 13C). In this manner, by using a semiconductor device in the system, information can be easily acquired, and high functionality and high added value are realized.

  In addition to the above, the semiconductor device manufactured by using the exposure method of the present invention has a wide range of applications, and any product that can be used for production, management, etc. without any contact and clarifying information such as the history of the object. It can also be applied to such things. For example, banknotes, coins, securities, certificate documents, bearer bonds, packaging containers, books, recording media, personal belongings, vehicles, foods, clothing, health supplies, daily necessities, chemicals, etc. It can be provided and used in an electronic device or the like. These examples will be described with reference to FIG.

  Banknotes and coins are money that circulates in the market, and include those that are used in the same way as money in a specific area (cash vouchers), commemorative coins, and the like. Securities refer to checks, securities, promissory notes, etc. (FIG. 14A). Certificates refer to driver's licenses, resident's cards, etc. (FIG. 14B). Bearer bonds refer to stamps, gift tickets, various gift certificates, etc. (FIG. 14C). Packaging containers refer to wrapping paper for lunch boxes, plastic bottles, and the like (FIG. 14D). Books refer to books, books, and the like (FIG. 14E). The recording media refer to DVD software, video tapes, and the like (FIG. 14F). The vehicles refer to vehicles such as bicycles, ships, and the like (FIG. 14G). Personal belongings refer to bags, glasses, and the like (FIG. 14H). Foods refer to food products, beverages, and the like. Clothing refers to clothing, footwear, and the like. Health supplies refer to medical equipment, health equipment, and the like. Livingware refers to furniture, lighting equipment, and the like. Chemicals refer to pharmaceuticals, agricultural chemicals, and the like. Electronic devices refer to liquid crystal display devices, EL display devices, television devices (television receivers, thin television receivers), cellular phones, and the like.

  Forgery can be prevented by providing the semiconductor device 80 on bills, coins, securities, certificates, bearer bonds, and the like. In addition, by providing semiconductor devices 80 in personal items such as packaging containers, books, recording media, personal items, foods, daily necessities, electronic devices, etc., the efficiency of inspection systems and rental store systems will be improved. Can do. By providing the semiconductor device 80 in vehicles, health supplies, medicines, etc., it is possible to prevent counterfeiting and theft, and in the case of medicines, it is possible to prevent mistakes in taking medicines. As a method of providing the semiconductor device 80, the semiconductor device 80 is provided by being attached to the surface of the article or embedded in the article. For example, a book may be embedded in paper, and a package made of an organic resin may be embedded in the organic resin. Even when the semiconductor device is provided on paper or the like, the element included in the semiconductor device can be prevented from being damaged by providing the semiconductor device by miniaturization using the exposure method described in the above embodiment mode. can do.

  In this way, by providing semiconductor devices in packaging containers, recording media, personal items, foods, clothing, daily necessities, electronic devices, etc., it is possible to improve the efficiency of inspection systems and rental store systems. it can. Further, forgery or theft can be prevented by providing a semiconductor device in the vehicles. Moreover, by embedding it in creatures such as animals, it is possible to easily identify individual creatures. For example, by embedding a semiconductor device equipped with a sensor in a living creature such as livestock, it is possible to easily manage health conditions such as body temperature as well as the year of birth, gender or type.

  Note that this embodiment can be freely combined with the above embodiment.

The figure which shows an example of the exposure method of this invention. The figure which shows an example of the exposure method of this invention. The figure which shows an example of the exposure method of this invention. The figure which shows an example of the exposure method of this invention. The figure which shows an example of the exposure method of this invention. The figure which shows an example of the exposure method of this invention. 8A and 8B illustrate an example of a method for manufacturing a semiconductor device using the exposure method of the present invention. 8A and 8B illustrate an example of a method for manufacturing a semiconductor device using the exposure method of the present invention. 8A and 8B illustrate an example of a method for manufacturing a semiconductor device using the exposure method of the present invention. 8A and 8B illustrate an example of a method for manufacturing a semiconductor device using the exposure method of the present invention. 8A and 8B illustrate an example of a method for manufacturing a semiconductor device using the exposure method of the present invention. 8A and 8B illustrate an example of a method for manufacturing a semiconductor device using the exposure method of the present invention. FIG. 6 shows an example of a usage pattern of a semiconductor device manufactured by using the exposure method of the present invention. FIG. 6 shows an example of a usage pattern of a semiconductor device manufactured by using the exposure method of the present invention.

Explanation of symbols

80 Semiconductor Device 81 High Frequency Circuit 82 Power Supply Circuit 83 Reset Circuit 84 Clock Generation Circuit 85 Data Demodulation Circuit 86 Data Modulation Circuit 87 Control Circuit 88 Memory Circuit 89 Antenna 91 Code Extraction Circuit 92 Code Determination Circuit 93 CRC Determination Circuit 94 Output Unit Circuit 101 Laser Oscillator 102 Beam splitter 103 Mirror 104 Magnifying optical system 105 Magnifying optical system 106 Mirror 107 Substrate 108 Mask original 109 Object beam 110 Reference beam 111 Hologram recording medium 112 Stage 112a Stage 112b Stage 113 Stage 113a Stage 113b Stage 114a Laser beam 114b Laser beam 121 Laser oscillator 122 Nonlinear optical element 122a Nonlinear optical element 122b Nonlinear optical element 123 Mirror 124 Magnifying optical system 125 Mirror 125a Mirror 125b Mirror 126 Mirror 126a Mirror 126b Mirror 127 Playback reference beam 128 Playback beam 129 Substrate 130 Resist 131 Laser beam 132 Prism 133 Beam splitter 134 Mirror 135 Mirror 141a Shutter 141b Shutter 141c Shutter 142 Laser beam 142a Laser beam 142b Laser beam 142c Laser beam 142d Laser beam 143 Laser beam 143a Laser beam 143b Laser beam 143c Laser beam 143d Laser beam 301 Inverter 302 Inverter 401 Substrate 402 Insulating film 403 Semiconductor film 404 Resist 405 Film 406 Metal 407a Resist 408a Semiconductor film 408b Semiconductor film 409 Gate insulating film 410 Conductive film 411 Resist 412 E Gram recording medium 413a resist 413b resist 414a gate electrode 414b gate electrode 415 impurity region 416 resist 417 high concentration impurity region 418 insulating film 419 resist 420 high concentration impurity region 421 insulating film 422 insulating film 423 resist 424 hologram recording medium 425a resist 425b resist 425c Resist 425d resist 425e resist 426a contact hole 426b contact hole 426c contact hole 426d contact hole 427 conductive film 428 resist 429 hologram recording medium 430a resist 430b resist 430c resist 430d resist 431a conductive film 431b conductive film 431c conductive film 431d conductive film 3200 reader / writer 3210 Display 3220 Item 3 30 semiconductor device 3240 reader / writer 3250 semiconductor device 3260 items

Claims (14)

Irradiating the hologram recording medium on which the hologram of the first pattern is recorded by irradiating the laser beam oscillated from the first laser oscillator with the laser beam oscillated from the second laser oscillator;
A step of forming a second pattern on the resist by irradiating the resist with laser light oscillated from the second laser oscillator through the hologram recording medium;
The wavelength of the laser beam that irradiates the resist through the hologram recording medium on which the hologram is recorded is shorter than the wavelength of the laser beam that is irradiated to record the hologram on the hologram recording medium, and the hologram is recorded. Therefore, the exposure method is characterized in that the reciprocal of 0.5 times the wavelength of the laser beam to be irradiated (n is an integer of 3 or more). Irradiating the hologram recording medium on which the hologram of the first pattern is recorded by irradiating the laser beam oscillated from the first laser oscillator with the laser beam oscillated from the second laser oscillator;
A step of forming a second pattern on the resist by irradiating the resist with laser light oscillated from the second laser oscillator through the hologram recording medium;
Using the same type of laser oscillator as the first laser oscillator and the second laser oscillator,
The wavelength of the laser beam irradiated to the resist through the hologram recording medium on which the hologram is recorded is made shorter than the wavelength of the laser beam irradiated to record the hologram on the hologram recording medium, and the hologram records A harmonic is used as a laser beam that passes through the hologram recording medium and irradiates the resist. Splitting the laser beam oscillated from the first laser oscillator to form a first laser beam and a second laser beam;
By irradiating the hologram recording medium with the first laser light through the mask on which the first pattern is formed, and simultaneously irradiating the hologram recording medium with the second laser light, the hologram recording medium is irradiated with the first laser light. Recording a hologram of one pattern;
By irradiating the hologram recording medium on which the hologram is recorded with the third laser light oscillated from a second laser oscillator, and irradiating the resist with the third laser light that has passed through the hologram recording medium, Forming a second pattern on the resist,
The wavelength of the third laser light is shorter than the wavelengths of the first laser light and the second laser light, and is 0.5 of the wavelength of the first laser light and the second laser light. An exposure method characterized in that it is a reciprocal multiple of n times (n is an integer of 3 or more). Splitting the laser beam oscillated from the first laser oscillator to form a first laser beam and a second laser beam;
By irradiating the hologram recording medium with the first laser light through the mask on which the first pattern is formed, and simultaneously irradiating the hologram recording medium with the second laser light, the hologram recording medium is irradiated with the first laser light. Recording a hologram of one pattern;
By irradiating the hologram recording medium on which the hologram is recorded with the third laser light oscillated from a second laser oscillator, and irradiating the resist with the third laser light that has passed through the hologram recording medium, Forming a second pattern on the resist,
Using the same type of laser oscillator as the first laser oscillator and the second laser oscillator,
The wavelength of the third laser light is shorter than the wavelengths of the first laser light and the second laser light,
An exposure method using harmonics as the third laser light. In claim 3 or claim 4,
An exposure method using a fundamental wave as the first laser light and the second laser light and using a harmonic as the third laser light. In claim 5,
An exposure method using a third harmonic as the third laser light. In claim 3 or claim 4,
An exposure method using harmonics as the first laser light, the second laser light, and the third laser light. In claim 7,
Using the second harmonic as the first laser light and the second laser light,
An exposure method using a third harmonic as the third laser light. In any one of Claims 1 thru | or 8,
An exposure method using a solid laser oscillator as the first laser oscillator and the second laser oscillator. In any one of Claims 1 thru | or 9,
An exposure method using a YAG laser oscillator, a YVO ₄ laser oscillator, a YLF laser oscillator, a YAlO ₃ laser oscillator, or a GdVO ₄ laser oscillator as the first laser oscillator and the second laser oscillator. Forming a semiconductor film on the substrate;
Forming a conductive film above the semiconductor film;
Forming a resist on the conductive film;
Irradiating the hologram recording medium on which the hologram of the first pattern is recorded by irradiating the laser beam oscillated from the first laser oscillator with the laser beam oscillated from the second laser oscillator;
Forming a second pattern on the resist by irradiating the resist with laser light oscillated from the second laser oscillator through the hologram recording medium;
The wavelength of the laser beam irradiated to the resist through the hologram recording medium on which the hologram is recorded is made shorter than the wavelength of the laser beam irradiated to record the hologram on the hologram recording medium, and the hologram is recorded. In order to achieve this, a method for manufacturing a semiconductor device is characterized in that the reciprocal is n times 0.5 (n is an integer of 3 or more) of the wavelength of the laser beam to be irradiated. Forming a semiconductor film on the substrate;
Forming a conductive film above the semiconductor film;
Forming a resist on the conductive film;
Irradiating the hologram recording medium on which the hologram of the first pattern is recorded by irradiating the laser beam oscillated from the first laser oscillator with the laser beam oscillated from the second laser oscillator;
Forming a second pattern on the resist by irradiating the resist with laser light oscillated from the second laser oscillator through the hologram recording medium;
Using the same type of laser oscillator as the first laser oscillator and the second laser oscillator,
The wavelength of the laser beam irradiated to the resist through the hologram recording medium on which the hologram is recorded is made shorter than the wavelength of the laser beam irradiated to record the hologram on the hologram recording medium, and the hologram records A method for manufacturing a semiconductor device, wherein harmonics are used as laser light that passes through the hologram recording medium and is applied to a resist. In claim 11 or claim 12,
A method for manufacturing a semiconductor device, wherein a solid-state laser oscillator is used as the first laser oscillator and the second laser oscillator. In any one of Claims 11 thru / or Claim 13,
A method for manufacturing a semiconductor device, wherein a YAG laser oscillator, a YVO ₄ laser oscillator, a YLF laser oscillator, a YAlO ₃ laser oscillator, or a GdVO ₄ laser oscillator is used as the first laser oscillator and the second laser oscillator.

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