TWI910985B - Exposure device and method thereof - Google Patents

Abstract

An exposure device and method for semiconductor manufacturing, focusing on the creation of exposure patterns with High Dynamic Range (HDR) capabilities, is disclosed. The exposure device includes a laser source, a first spatial light modulator (SLM), specifically a Liquid Crystal on Silicon (LCOS) device, and a second SLM, specifically a Digital Micromirror Device (DMD). The LCOS is positioned upstream in the optical path and is optimized for modulating the phase of the laser. It also directs the laser light towards specific areas on the DMD, crucial for enhancing detail and contrast in exposure patterns. The DMD, placed downstream, is composed of micromirrors that modulate the amplitude of the reflected laser, essential for achieving HDR in exposure patterns. This cooperative interaction between the LCOS and DMD allows for the creation of exposure patterns with a wide range of light intensities, from very bright to very dark, thereby achieving high dynamic range.

Description

Exposure apparatus and exposure method

A semiconductor manufacturing apparatus, particularly an exposure apparatus.

Photolithography is a process that uses exposure and development to create geometric patterns on a photoresist layer. The pattern is then transferred to a substrate via etching. This substrate can be a silicon wafer or silicon carbide substrate used in semiconductors, or a printed circuit board (PCB) used in general electronic components. In this process, the photomask becomes one of the key components determining the exposure pattern. However, photomasks require complex procedures such as design, testing, and verification, which can take several months to complete, thus extending the manufacturing time of semiconductor devices.

To overcome the problems associated with photomasks, maskless lithography has gradually gained market favor. As the name suggests, maskless lithography is a method that exposes photoresist (PR) without using a mask/reticle to create patterns, thus eliminating the need for a mask and achieving the effect of maskless exposure. Currently, maskless lithography is widely used for components produced in small batches with high variety, such as inductors, passive components, and microelectromechanical systems (MEMS).

Currently, common photomask-less exposure machines generate exposure patterns on photoresist layers using Liquid Crystal On Silicon (LCOS) devices or Digital Micromirror Devices (DMDs). However, these methods all have their drawbacks. For example, LCOS liquid crystals have a slower modulation speed, requiring longer exposure times, which does not meet market demands for high-speed semiconductor device production.

Please refer to Figures 1A and 1B, which illustrate the development of a photoresist layer after exposure using a digital microscopy device. In Figures 1A and 1B, a photoresist layer 11 is disposed on a wafer 10, and a predetermined area 13 on the photoresist layer 11 is exposed using a digital microscopy device. Then, in Figure 1B, after development, a portion of the photoresist layer 11 is removed to form a pattern 12. However, due to diffraction, light often cannot be 100% concentrated in the predetermined exposed area, and the predetermined non-exposed areas are often also partially illuminated (especially near the edges of the predetermined exposed area). Therefore, the actual formed pattern 12 does not have an edge 14 perpendicular to the wafer 10 as the predetermined area 13, but rather deviates from it. Edge 14 may be beveled, and its location may be smaller or larger than the predetermined area 13, preventing the pattern 12 from forming correctly in the predetermined position. In other words, if a DMD is used for exposure, because the phase cannot be changed, the pattern shape cannot be precisely or sharply controlled during development, resulting in a less than expected development result (poor yield), which is particularly noticeable in exposures with thick photoresist.

Therefore, how to solve the above problems is a question worth considering for those with general knowledge in this field.

This invention relates to an advanced exposure apparatus and a corresponding method specifically designed for projecting lasers onto a photoresist layer. The invention introduces significant improvements in semiconductor manufacturing, particularly focusing on creating exposure patterns with High Dynamic Range (HDR) characteristics. These advancements address the demands for higher precision and efficiency in semiconductor patterning processes, solving some key challenges in modern manufacturing.

The core of the exposure apparatus consists of a laser light source, a first spatial light modulator, and a second spatial light modulator. The first spatial light modulator, located upstream in the optical path, is a liquid crystal on silicon (LCOS) device responsible for modulating the phase of the incident laser. This modulator contains multiple first pixels, each designed to reflect the laser after phase modulation. Furthermore, the LCOS device is also designed to direct laser light to specific areas on the second spatial light modulator, thus playing a crucial role in the accuracy and detail of the final exposed pattern.

In the optical path, the second spatial light modulator is located downstream of the first spatial light modulator, specifically in the digital micromirror device (DMD). The DMD consists of multiple second pixels or micromirrors, each used to modulate the amplitude of the reflected laser. This modulation is crucial for achieving the high dynamic range characteristics of the exposure pattern, providing a range of light intensities that translate into richer detail and contrast in the final image.

The collaboration between the first and second spatial light modulators is crucial for creating exposure patterns with high dynamic range characteristics. The first spatial light modulator first optimizes the direction of phase-modulated laser light and directs it to the second spatial light modulator. The second spatial light modulator then fine-tunes the amplitude of this directed laser, thereby adding depth and contrast to the exposure pattern. This synergy allows for the creation of exposure patterns with a wide range of light intensities, encompassing areas from very bright to very dark, thus achieving high dynamic range.

Furthermore, the innovative arrangement of the first and second spatial light modulators in the optical path significantly affects the speed and efficiency of the exposure process. By placing the first spatial light modulator upstream and the second downstream, the device utilizes the inherent speed of light within the optical path. This arrangement effectively compensates for the slower modulation speed of the first spatial light modulator, ensuring that the faster modulation activity of the second spatial light modulator does not become a bottleneck. Moreover, minute adjustments to the light angle by the first spatial light modulator result in a significant positional shift at the second spatial light modulator due to the optical path length between them. This characteristic allows for precise control of the light distribution on the photoresist layer, improving the accuracy of the exposure pattern.

The exposure apparatus also includes a projection lens mounted between the second spatial light modulator and the photoresist layer to focus the laser reflected from the second spatial light modulator onto the photoresist layer to form an exposure pattern. Additionally, the apparatus includes a expander positioned in the laser path to illuminate the first spatial light modulator.

The corresponding exposure method for the aforementioned apparatus includes steps of emitting a laser, modulating its phase and amplitude, and projecting it onto a photoresist layer, aiming to fully utilize the high dynamic range characteristics of the apparatus. This method includes guiding the laser to a specific area on a second spatial light modulator according to the modulation of a first spatial light modulator, and dynamically adjusting the contrast and intensity of the laser light to create an exposure pattern with high dynamic range characteristics.

This invention provides a sophisticated solution to the challenges of semiconductor exposure processes, enhancing the ability to create detailed and high-contrast patterns for advanced semiconductor manufacturing. The innovative exposure apparatus and method represent a significant advancement in semiconductor manufacturing technology, offering enhanced accuracy, efficiency, and adaptability in exposure patterns.

10: Wafers

11: Photoresist layer

12: Pattern

13: Pre-selected area

14: Edge

100: Exposure Device

110: Laser light source

111, 111a, 111b: Laser light

111b’: First laser beam

111b”: Second laser beam

112: Diver

120: First Spatial Light Modulator

130: Second Spatial Lighting Maker

140: Sensor

141: Phase Sensor

142: Light Intensity Sensor

143, 143': Beam Spectroscope

150: Controller

151: Input Interface

160: Projection Lens

20: Photoresist layer

201: First Pixel

2011: First Dark Area Pixels

2012a, 2012b: First Dark Area Pixels

210:Substrate layer

220: CMOS layer

230: Reflective layer

240, 240’: Orientation layer

250:Liquid crystal layer

251:LCD

260: Transparent Electrode Layer

270: Glass cover plate

280: Anti-reflective layer

310:Substrate

320: Microscope

400: Exposure Pattern

401: Third Pixel

410: Third dark area pixel

420, 420': Third bright area pixels

430: Light and Shadow Edges

601, 602: Curves

S11~S16, S161~S165: Step symbols

Figures 1A and 1B illustrate the exposure and development of a photoresist layer using a DMD.

Figure 2A illustrates the exposure device of this invention.

Figure 2B shows a schematic diagram of the exposure apparatus.

The schematic diagram shown in Figure 3A illustrates an embodiment of a liquid crystal silicon-coated device, where the first spatial light modulator is a first example.

Figure 3B shows a schematic diagram of the exterior of the first spatial light modulator.

Figure 4 shows a schematic diagram of the second spatial light modulator.

Figure 5 shows a schematic diagram of the formation of an exposure pattern.

Figure 6A shows a schematic diagram of the first pixel.

Figure 6B shows a schematic diagram of the exposure pattern formed by laser light.

Figure 6C shows a schematic diagram of the light intensity on the third pixel at a given time point.

This invention provides an exposure apparatus and method that uses a spatial light modulator to modulate the phase and amplitude of laser light, and utilizes the interference and cancellation of laser light with different phases and amplitudes to form a more precise exposure pattern. Please refer to Figures 2A and 2B. Figure 2A illustrates the exposure apparatus of this invention. Figure 2B shows a schematic diagram of the structure of the exposure apparatus. The exposure apparatus 100 of this invention includes a laser light source 110, a beam expander 112, a first spatial light modulator 120, a second spatial light modulator 130, a sensor 140, a controller 150, and a projection lens 160.

First, step S11 is executed, emitting a laser light 111 to the first spatial light modulator 120. In step S11, the laser light 111 is emitted using a laser light source 110. The first spatial light modulator 120 is positioned in the path of the laser light 111 and is illuminated by the laser light 111. A expander 112 is positioned between the laser light source 110 and the first spatial light modulator 120, and is positioned in the path of the laser light 111, so the laser light 111 passes through the expander 112 to illuminate the first spatial light modulator 120. When the laser light 111 passes through the expander 112, the illumination radius of the laser light 111 is magnified, which increases the area of the laser light 111 illuminating the first spatial light modulator 120. In one embodiment, when laser light 111 passes through expander 112, it covers the entire first spatial light modulator 120. In this embodiment, the first spatial light modulator 120 is, for example, a Liquid Crystal On Silicon (LCOS) device. Therefore, the first spatial light modulator 120 includes multiple first pixels 201, each adapted to phase-modulate the laser light 111 incident upon it and reflect the laser light 111. The phase of the reflected laser light 111a can be changed. Therefore, in step S12, the first spatial light modulator 120 changes the phase of the laser light 111 modulated by each first pixel 201.

Please refer to Figure 3A, which is a schematic diagram of a liquid crystal silicon-coated device as an embodiment of a first spatial light modulator. The liquid crystal silicon-coated device as the first spatial light modulator 120 includes a substrate layer 210, a CMOS layer 220 (CMOS is an abbreviation for Complementary Metal-Oxide-Semiconductor), a reflective layer 230, two alignment layers 240 and 240', a liquid crystal layer 250, a transparent electrode layer 260, and a glass cover plate 270. The CMOS layer 220 includes a CMOS circuit layer 221 and multiple pixel electrodes 222. A reflective layer 230 is disposed on the CMOS layer 220, an alignment layer 240 is disposed above the reflective layer 230, and a liquid crystal layer 250 is disposed between the two alignment layers 240 and 240'. A transparent electrode layer 260 is disposed above the alignment layer 240', and multiple transparent electrodes (not shown) are disposed on the transparent electrode layer 260. Each transparent electrode corresponds to one of the pixel electrodes 222; that is, the transparent electrodes and pixel electrodes 222 are arranged in pairs. The glass cover 270 covers the transparent electrode layer 260 and, in addition to receiving external light, also protects the internal components of the liquid crystal silicon-coated device. Furthermore, an anti-reflective layer 280, such as an anti-reflection coating, is disposed above the glass cover 270.

Please also refer to Figure 3B, which is a schematic diagram of the liquid crystal silicon-coated device serving as the first spatial light modulator 120. The viewing plane of the liquid crystal silicon-coated device can be divided into multiple first pixels 201, each first pixel 201 corresponding to a pixel electrode 222 and a transparent electrode. In this embodiment, the liquid crystal silicon-coated device receives external control signals via the CMOS circuit layer 221, thereby controlling the electrical properties of the pixel electrode 222 and the transparent electrode on the transparent electrode layer 260, thus causing the liquid crystal 251 in the liquid crystal layer 250 corresponding to each pixel electrode to rotate. In this way, when light enters the liquid crystal silicon-coated device, it is affected by the rotated liquid crystal 251, and its phase will be changed. Furthermore, the direction of the liquid crystal 251 corresponding to each first pixel 201 can be controlled by individual pixel electrodes 221 and transparent electrodes, thus allowing control over the phase of the light emitted by each first pixel 201.

Next, referring back to Figure 2A, proceed to step S13, illuminating the laser light 111a, whose phase has been modulated by the first spatial light modulator 120, onto the second spatial light modulator 130. The second spatial light modulator 130 is positioned along the path of the laser light 111a reflected by the first spatial light modulator 120. Furthermore, the second spatial light modulator 130 includes multiple second pixels, each adapted to modulate the amplitude of the laser light 111a illuminating it before reflecting the laser light 111a. In this embodiment, the second spatial light modulator 130 is a digital micromirror device (DMD) capable of reflecting the laser light 111a, and the amplitude of the reflected laser light 111b is altered. Therefore, in step S14, the second spatial light modulator 130 changes the amplitude of the laser light 111b modulated by the second pixel.

Further, please refer to Figure 4, which is a schematic diagram of a second spatial light modulator. In one embodiment, the second spatial light modulator 130 further includes a plurality of second pixels, which in this embodiment are micromirrors 320, disposed on a substrate 310. In this embodiment, each micromirror 320 corresponds to one of the first pixels 201 (see Figure 3B) on the first spatial light modulator 120. Each micromirror 320 can be controlled and its angle can be changed, so that the micromirror 320 presents an on or off effect, for example, positive 12 degrees to the horizontal plane for on and negative 12 degrees for off, and the frequency of switching between on and off of each micromirror 320 can also be controlled. By adjusting the switching frequencies of different micromirrors 320 to reflect laser light 111a, the laser light 111a reflected by micromirrors 320 at different switching frequencies can accumulate different energies, thereby adjusting the amplitude (i.e., intensity) of the laser light 111a illuminating the photoresist layer 20. The laser light 111b, after being reflected by the second spatial light modulator 130, is then projected onto the photoresist layer 20 by the projection lens 160 to form an exposure pattern 400 (as shown in Figure 5).

Please refer back to Figure 2A. Then proceed to step S15, where laser light 111b, modulated by the second spatial light modulator 130, illuminates the photoresist layer 20, forming an exposure pattern 400. After passing through the first spatial light modulator 120, the phase of the laser light emitted from each first pixel 201 can be adjusted. Furthermore, after passing through the second spatial light modulator 130, the intensity distribution of the laser light illuminating the photoresist layer 20 is adjusted, thereby forming a light and dark distribution on the surface of the photoresist layer 20, resulting in the exposure pattern 400 shown in Figure 5.

Please refer to Figure 5, which is a schematic diagram of the exposure pattern. The exposure pattern 400 can be considered as being composed of multiple third pixels 401 arranged in an array. The third pixels 401 include a third dark area pixel 410 and a third bright area pixel 420, and each third pixel 401 corresponds to one of the first pixels 201 on the first spatial modulator 120 and one of the micromirrors 320 on the second spatial modulator 130.

The third pixel 401 corresponds to a first pixel 201 comprising multiple first dark area pixels and multiple first bright area pixels, with the third dark area pixel 410 corresponding to a first dark area pixel and the third bright area pixel 420 corresponding to a first bright area pixel. The laser light modulated by at least two first bright area pixels adjacent to the first dark area pixel is 180° out of phase with each other.

Please refer to Figure 6A, which is a schematic diagram of the first pixels. Figure 6A only shows three first pixels 201 for illustration, including one first dark area pixel 2011 and two adjacent first bright area pixels 2012a and 2012b. In this embodiment, the first bright area pixels 2012a and 2012b are located to the left and right of the first dark area pixel 2011, respectively. After the first bright area pixels 2012a and 2012b modulate the laser light, the phase of the modulated laser light differs from each other by 180°. In other words, the laser light modulated by the first bright area pixels 2012a and 2012b will have a 180° phase difference.

Next, please refer to Figure 6B, which shows a schematic diagram of the laser light forming an exposure pattern. The laser light reflected by the first bright pixel 2012a is projected onto the third bright pixel 420, and the laser light reflected by the first bright pixel 2012b is projected onto the third bright pixel 420'.

Next, please refer to Figure 6C, which shows a schematic diagram of the light intensity on the third pixel at a given time point. Curve 601 represents the light intensity of the laser light reflected from the first bright pixel 2012a and projected onto the third bright pixel 420. Curve 602 represents the light intensity of the laser light reflected from the first bright pixel 2012b and projected onto the third bright pixel 420'. Due to light diffraction, some laser light is projected onto the third dark pixel 410. The laser light reflected by the first bright pixels 2012a and 2012b has a 180° phase difference, therefore the phases of the laser light projected onto the third bright pixels 420 and 420' are opposite to each other. Therefore, the laser light projected onto the third dark pixel 410 due to diffraction is canceled out by the interference of the laser light reflected from the first bright pixels 2012a and 2012b. This effectively reduces the light projection onto the third dark pixel 410, further making the distinction between the third bright pixel 420 and the third dark pixel 410 clearer when forming the exposure pattern.

The mirror 320 corresponding to the third pixel 401 of the third dark area pixel 410 is deflected at an angle such that reflected laser light does not illuminate the third dark area pixel 410. Conversely, the mirror 320 corresponding to the third pixel 401 of the third bright area pixel 420 is deflected at an angle such that reflected laser light illuminates the third bright area pixel 420.

In this embodiment, an exposure pattern 400 with high dynamic range characteristics can be achieved through the collaborative interaction between the first spatial light modulator 120 and the second spatial light modulator 130, thereby creating a highly detailed exposure pattern 400. In this embodiment, high dynamic range refers to the ability of the exposure apparatus 100 to create an exposure pattern with a significantly wider range of light intensity, providing richer detail and contrast. This is achieved through the collaborative interaction between the first spatial light modulator 120 (hereinafter referred to as LCOS) and the second spatial light modulator 130 (hereinafter referred to as DMD). As the first spatial light modulator 120, the LCOS not only optimizes the phase of the laser 111 but also precisely directs the laser 111 to a specific area on the second spatial light modulator 130. This targeted guidance is crucial for focusing light intensity to the desired location, thereby enhancing the effect of the second spatial light modulator 130 in creating a highly detailed exposure pattern 400. The DMD, acting as the second spatial light modulator 130, plays a key role in dynamically adjusting the amplitude and contrast of the laser 111, further refining the exposure pattern 400. The dynamic modulation capability of the DMD is essential for realizing the full potential of the high dynamic range, allowing the creation of an exposure pattern 400 with improved accuracy and contrast levels.

In other words, by directing the laser 111 towards the micromirror 320 on the second spatial light modulator 130 that should be illuminated, instead of illuminating areas that shouldn't be illuminated, the third dark pixel 410 in the exposure pattern 400 becomes darker, while the third bright pixel 420 becomes brighter, thus making energy utilization more efficient. In other words, without a high dynamic range, the micromirror 320 corresponding to the third dark pixel 410 would simply redirect the laser 111 illuminating it to areas outside the third dark pixel 410, essentially wasting that portion of the laser 111.

In addition to its high dynamic range characteristics, this invention also details an innovative arrangement of the optical path, specifically placing the first spatial light modulator 120 upstream of the laser path and the second spatial light modulator 130 downstream. This arrangement utilizes the inherent speed of light, effectively compensating for the slower modulation speed (in the kilohertz range) of the first spatial light modulator 120. By placing the first spatial light modulator 120 upstream, it modulates the laser 111 first, thereby ensuring that the subsequent faster modulation (in the megahertz range) performed by the second spatial light modulator 130 is not blocked by the slower first spatial light modulator 120. The distance between the first spatial light modulator 120 and the second spatial light modulator 130 in the optical path plays a crucial role here. Even a minute adjustment to the light angle by the first spatial modulator 120 will result in a significant positional shift when the light reaches the second spatial modulator 130 due to the optical path length. This strategic placement not only optimizes laser usage but also significantly improves the overall speed and efficiency of the exposure process.

The integration of high dynamic range characteristics with the meticulous arrangement of optical components represents a significant advancement in exposure device technology. It has played a crucial role in addressing some key challenges in modern semiconductor manufacturing, particularly in the accuracy, efficiency, and adaptability of exposure patterns.

Next, we will describe in more detail how the first spatial light modulator 120 and the second spatial light modulator 130 work together to achieve an exposure pattern 400 with high dynamic range characteristics. As an embodiment of the first spatial light modulator 120 in the optical path, LCOS is traditionally recognized for its ability to modulate the phase of the laser 11. In this embodiment, the LCOS is not limited to its traditional role but also directs the laser light to specific areas on the DMD. This directional control is crucial for focusing the light intensity to the most beneficial areas, especially in areas requiring high detail and contrast.

Each pixel of the first spatial light modulator 120, also referred to as first pixel 201, as shown in Figure 3B, comprises a liquid crystal layer 250. These pixels are precisely aligned to modulate the phase of the incident laser 11. When the laser 11 is modulated, the first spatial light modulator 120 also causes subtle but significant directional changes. These changes play a crucial role in shaping the trajectory of the laser 11 toward the second spatial light modulator 130. This control is achieved by manipulating the orientation of the liquid crystal 251, thereby altering the path of the laser 11 through refraction. This precise manipulation at the level of the first spatial light modulator 120 ensures that the laser reaches the second spatial light modulator 130 with an optimized distribution, laying the foundation for the effective implementation of high dynamic range characteristics.

Following the first spatial light modulator 120 is the DMD, an embodiment of the second spatial light modulator 130 in the optical path. Its primary role is to modulate the amplitude of the laser 11, a function now crucial for achieving high dynamic range characteristics. The second spatial light modulator 130, composed of thousands of micromirrors 320, each corresponding to a single pixel and also referred to as the second pixel 320, is capable of extremely rapid and precise adjustments.

The micromirrors 320 of the DMD rotate according to control signals from the controller 150, adjusting the angle at which they reflect the incident laser 11. These minute adjustments cause changes in the intensity and contrast of the light projected onto the photoresist layer 20. The DMD's ability to rapidly switch states (i.e., the on and off positions of the micromirrors) allows for dynamic modulation of the laser 11. This rapid modulation is crucial for creating exposure patterns 400 with high contrast and fine detail, i.e., high dynamic range characteristics.

In summary, the collaborative interaction between the first spatial light modulator 120 and the second spatial light modulator 130 is key to achieving the high dynamic range characteristics in the exposure pattern 420. The first spatial light modulator 120 first guides the phase-modulated laser 11 to the second spatial light modulator 130 in an optimized manner. Then, the DMD second spatial light modulator 130 fine-tunes this guided laser 11, adding depth and contrast to the exposure pattern 420. This collaborative action allows for the creation of an exposure pattern 420 with a wide range of light intensities, from very bright to very dark, thus achieving high dynamic range.

Referring again to Figure 2A, in one embodiment, the sensor 140 is positioned between the second spatial light modulator 130 and the photoresist layer 20. Therefore, step S16 is performed to detect the phase and intensity of the laser light 111b from the second spatial light modulator 130. Furthermore, the projection lens 160 is placed along the path of the laser light 111b reflected from the second spatial light modulator 130. After passing through the projection lens 160, the laser light 111b is projected onto the photoresist layer 20 to form an exposure pattern 400 on the photoresist layer 20.

In a preferred embodiment, the sensor 140 includes multiple beam splitters 143 and 143', a light intensity sensor 142, and a phase sensor 141. Beam splitter 143' is disposed between the second spatial light modulator 130 and the projection lens 160. Beam splitter 143' is adapted to split the incident laser light 111b into a first laser light 111b' and a second laser light 111b'. Further, the ratio of the light intensity of the first laser light 111b' to the light intensity of the second laser light 111b' is 99, meaning that beam splitter 143' will separate 1% of the laser light into the light intensity sensor 142 and the phase sensor 141. In the embodiment shown in Figure 2A, the second laser beam 111b” is further split by a beam splitter 143, allowing it to be incident on both the light intensity sensor 142 and the phase sensor 141. The sensor 140 generates a sensing signal by receiving the second laser beam 111b” through the light intensity sensor 142 and the phase sensor 141.

Referring to Figure 2B, the controller 150 is electrically connected to the laser light source 110, the first spatial light modulator 120, the second spatial light modulator 130, and the sensor 140. The controller 150 is, for example, a programmable logic controller (PLC) or a computer device with a control program. The controller 150 is adapted to receive sensing signals and control the output light intensity and phase of the laser light source 110 according to the sensing signals. The control method is as follows: First, in step S161, a beam splitter 143' is used to split the laser light 111b into a first laser light 111b' and a second laser light 111b'", where the first laser light 111b' is the laser light that was directed towards the photoresist layer 20 in step S15. Next, in step S162, the second laser light 111b' is directed towards a light intensity sensor 142 and a phase sensor 141. Further, another beam splitter 143 is used to allow the second laser light 111b' to enter the light intensity sensor 142 and the phase sensor 141 respectively.

Next, step S163 is performed to detect the light intensity of the second laser light 111b” using the light intensity sensor 142. Then, step S164 is performed to detect the phase of the second laser light 111b” using the phase sensor 141. Next, step S165 is executed, controlling the first light modulator 120 and the second light modulator 130 according to the phase and intensity of the second laser light 111b” to further correct the formed exposure pattern 400. Furthermore, in one embodiment, steps S15 and S16 (i.e., steps S161-S165) are performed simultaneously. That is, while forming the exposure pattern 400, the exposure pattern 400 formed by the laser light can be dynamically adjusted through steps S161-S165, continuously correcting the exposure pattern 400 during the exposure process, further ensuring that the exposure pattern 400 conforms to the expected pattern.

More specifically, the controller 150 compares the laser parameters measured by the sensor 140 with preset laser parameters. If the measured laser parameters do not match the preset laser parameters, the controller controls the laser light source 110 to adjust the intensity and phase of the emitted laser light until the laser parameters measured by the sensor 140 match the preset laser parameters.

Furthermore, in one embodiment, the controller 150 also includes an input interface 151, which allows the operator to input desired preset laser parameters. Additionally, the input interface 151 is also suitable for the operator to input a desired exposure pattern. Based on the input exposure pattern data, the controller 150 can further operate the first spatial light modulator 120 and the second spatial light modulator 130 to form the desired exposure pattern on the photoresist layer 20.

The exposure apparatus and method provided by this invention, by modulating the phase and amplitude of laser light, utilizes the mutual interference and cancellation of laser light between each pixel to form a more precise or sharper exposure pattern, thereby improving the yield of developing processes and overcoming the shortcomings of traditional techniques.

The invention is described above, but it is not intended to limit the scope of the patent rights claimed in this work. The scope of patent protection shall be determined by the appended scope of the patent application and its equivalent fields. Any modifications or alterations made by those skilled in the art, without departing from the spirit or scope of this patent, constitute equivalent changes or designs made under the spirit disclosed in this invention and should be included within the scope of the patent application below.

100: Exposure Device

111, 111a, 111b: Laser light

111b’: First laser beam

111b”: Second laser beam

112: Diver

120: First Spatial Light Modulator

130: Second Spatial Lighting Maker

140: Sensor

141: Phase Sensor

142: Light Intensity Sensor

143, 143': Beam Spectroscope

150: Controller

160: Projection Lens

Claims (10)

An exposure apparatus for projecting laser onto a photoresist layer, the exposure apparatus comprising: a laser source for emitting laser; a first spatial light modulator irradiated by the laser, comprising a plurality of first pixels, each first pixel for reflecting the laser irradiated thereon and having its phase modulated, wherein the first spatial light modulator is a liquid crystal silicon-coated device disposed upstream of the optical path; and a second spatial light modulator irradiated by the laser reflected by the first spatial light modulator, comprising a plurality of second pixels, each second pixel for reflecting the laser irradiated thereon and having its amplitude modulated, wherein the second spatial light modulator is a digital micromirror device disposed downstream of the optical path, comprising a plurality of micromirrors serving as the second pixels; A controller is electrically connected to the laser light source, the first spatial light modulator, and the second spatial light modulator for controlling the laser light source, the first spatial light modulator, and the second spatial light modulator; wherein the first spatial light modulator and the second spatial light modulator are configured to jointly create an exposure pattern with high dynamic range characteristics, the exposure pattern including a plurality of third pixels, and the first pixel and the second pixel respectively correspond to the third pixels. According to the exposure apparatus of claim 1, the high dynamic range characteristic of the exposure pattern is achieved by guiding the laser to a specific area on the second spatial light modulator via the first spatial light modulator, and by the second spatial light modulator dynamically adjusting the contrast and intensity of the laser on the exposure pattern. According to the exposure apparatus of claim 1, the first spatial light modulator modulates the phase of the laser at a speed in the kilohertz range, while the second spatial light modulator modulates the amplitude of the laser at a speed in the megahertz range. According to claim 1 or claim 3, in the exposure apparatus, due to the optical path length between the first spatial light modulator and the second spatial light modulator, a small adjustment of the light angle by the first spatial light modulator will cause a significant positional shift of the light at the second spatial light modulator. This positional shift can compensate for the slower modulation speed of the first spatial light modulator and precisely control the distribution of the laser on the photoresist layer, thereby improving the accuracy of the exposure pattern. The exposure apparatus according to claim 1 further includes a projection lens mounted between a second spatial light modulator and a photoresist layer, wherein the projection lens focuses a laser reflected by the second spatial light modulator and illuminates the laser onto the photoresist layer to form the exposure pattern. According to the exposure apparatus of claim 1, the third pixel includes a plurality of third dark area pixels and a plurality of third bright area pixels, the first pixel includes a plurality of first dark area pixels and a plurality of first bright area pixels, and the third dark area pixels correspond to the first dark area pixels, and the third bright area pixels correspond to the first bright area pixels; wherein the laser light modulated by at least two of the first bright area pixels adjacent to the first dark area pixels is 180˚ out of phase with each other. A method for projecting a laser onto a photoresist layer using an exposure apparatus includes the following steps: emitting a laser from a laser source; modulating the phase of the laser using a first spatial light modulator comprising a plurality of first pixels, wherein the first spatial light modulator is located upstream of the optical path; reflecting the phase-modulated laser onto a second spatial light modulator comprising a plurality of second pixels, wherein the second spatial light modulator is located downstream of the optical path; modulating the amplitude of the laser using the second spatial light modulator, including dynamically adjusting the contrast and intensity of the laser; and projecting the laser onto the photoresist layer to form an exposure pattern having high dynamic range characteristics, wherein the exposure pattern includes a plurality of third pixels corresponding to the first and second pixels. According to the method of claim 7, the high dynamic range characteristic of the exposure pattern is achieved by directing a laser to a specific area on the second spatial light modulator, based on the modulation of the first spatial light modulator. According to the method of claim 7, the phase of the laser is modulated by the first spatial light modulator at a speed in the kilohertz range, and the amplitude of the laser is modulated by the second spatial light modulator at a speed in the megahertz range. According to the method of claim 7, a small adjustment of the light angle by the first spatial light modulator will cause a significant positional shift of the light at the second spatial light modulator due to the optical path length between them, thereby compensating for the slower modulation speed of the first spatial light modulator and precisely controlling the distribution of the laser on the photoresist layer, and improving the accuracy of the exposure pattern.