JP2021049535A - Laser irradiation device and method for manufacturing resin molding - Google Patents

Abstract

To provide a laser irradiation device capable of suppressing variations in line widths of patters.SOLUTION: An exposure device 1 includes: an irradiation unit 30 for irradiating a substrate 50 with pulse laser light L; a moving unit 20 for moving the pulse laser light L on the substrate 50; detection means 214, 224 and 42 for detecting moving speed vH in a horizontal direction of the irradiation unit 30; and a control device 40 for controlling the irradiation unit 30 and the moving unit 20, in which the control device 40 controls the irradiation unit 30 so as to intermittently emit the pulse laser light L for each constant moving distance, and controls the irradiation unit 30 so that a pulse width WP becomes larger as the moving speed vH is lower.SELECTED DRAWING: Figure 2

Description

The present invention relates to a laser irradiation device and a method for manufacturing a resin molded product.

A scanning optical system is known in which a plurality of light beams modulated according to an image density are focused on a recording material by an optical system and scanned (see, for example, Patent Document 1). In this scanning optical system, the intensity of the light beam is controlled in order to keep the integrated exposure amount constant when the pulse width is modulated.

Japanese Unexamined Patent Publication No. 2001-281574

However, when the line width of the drawing pattern is narrow, there is a problem that the line width of the drawing pattern may vary even if the integrated exposure amount is constant as described above.

An object to be solved by the present invention is to provide a laser irradiation device and a method for manufacturing a resin molded product, which can suppress variations in line width of a pattern.

[1] The laser irradiation device according to the present invention includes an irradiation means for irradiating a work with pulsed laser light, a moving means for moving the pulsed laser light on the work, and a movement of the pulsed laser light on the work. The detection means for detecting the speed and the control means for controlling the irradiation means and the movement means are provided, and the control means intermittently irradiates the pulsed laser beam at regular movement distances. It is a laser irradiation device that controls the irradiation means and controls the irradiation means so that the pulse width of the pulsed laser light increases as the moving speed becomes slower.

[2] In the above invention, the moving means is a moving unit that moves the work relative to the irradiation means, and the moving speed may be the relative speed of the work with respect to the irradiation means.

[3] In the above invention, the control means has a second movement speed that is slower than the first movement speed than the first integrated exposure amount when the movement speed is the first movement speed. The irradiation means may be controlled so that the second integrated exposure amount at the moving speed becomes large.

[4] In the above invention, when the moving speed is the first moving speed, the duty ratio is 40% or more and 60% or less, and when the moving speed is the second moving speed, the duty ratio is 40%. It may be less than.

[5] In the above invention, the control means may control the irradiation means so that the lap rate of the pulsed laser light is 50% or more and 90% or less.

[6] In the above invention, the work includes a resin layer containing a photopolymerization initiator, and the irradiation means may irradiate the resin layer with the pulsed laser light.

[7] In the above invention, the line width of the pattern drawn by the pulsed laser beam on the resin layer may be 10 μm or less.

[8] The method for producing a resin molded product according to the present invention is a method for producing a resin molded product by irradiating a resin portion with a pulse laser beam and moving the resin molded product on the resin portion. This is a method for manufacturing a resin molded product in which pulsed laser light is intermittently irradiated and the pulse width of the pulsed laser light is increased as the moving speed of the pulsed laser light on the resin portion is slower.

According to the present invention, pulsed laser light is intermittently irradiated at regular movement distances, and the pulse width is increased as the movement speed is slower, so that variation in the line width of the pattern can be suppressed.

FIG. 1 is a perspective view showing an exposure apparatus according to an embodiment of the present invention. FIG. 2 is a diagram showing a configuration of an irradiation unit according to an embodiment of the present invention. FIG. 3 is a block diagram showing a configuration of a control system according to an embodiment of the present invention. FIG. 4 is an explanatory diagram for explaining the definition of the lap ratio. FIG. 5 is a graph for explaining the relationship between the moving speed of the irradiation unit and the pulse width of the pulsed laser beam in the embodiment of the present invention. FIG. 6 is a diagram for explaining a chemical reaction of a resist material accompanying exposure of a pulsed laser beam, and is a diagram for explaining a case where the moving speed of the irradiation unit is normal. FIG. 7 is a diagram for explaining the chemical reaction of the resist material accompanying the exposure of the pulsed laser beam, and is a diagram for explaining the case where the moving speed of the irradiation unit is slow.

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

FIG. 1 is a perspective view showing an exposure apparatus according to the present embodiment, FIG. 2 is a diagram showing a configuration of an irradiation unit according to the present embodiment, and FIG. 3 is a block diagram showing a configuration of a control system according to the present embodiment. , FIG. 4 is an explanatory diagram showing the definition of the lap ratio.

The exposure device 1 in the present embodiment is a direct drawing type exposure device that directly irradiates the substrate 50 with processing light without using a mask (or reticle) or the like. A chemically amplified resist layer 51 is formed on the surface of the substrate 50, and the exposure apparatus 1 scans the resist layer 51 while irradiating it with processing light to draw a pattern on the resist layer 51. After that, the resist layer 51 is rinsed with a developing solution such as an alkaline solution to develop a pattern on the surface of the substrate 50. In the present embodiment, the resist layer 51 contains a photoacid generator as a photopolymerization initiator. The exposure apparatus 1 in the present embodiment corresponds to an example of the "laser irradiation apparatus" in the present invention, and the substrate 50 having the resist layer 51 in the present embodiment corresponds to an example of the "work" in the present invention. The resist layer 51 corresponds to an example of the "resin layer" and the "resin portion" in the present invention, the photoacid generator in the present embodiment corresponds to an example of the "photopolymerization initiator" in the present invention, and the resist after development. The layer 51 corresponds to an example of the "resin molded product" in the present invention.

As shown in FIGS. 1 to 3, the exposure device 1 includes a stage 10, a moving unit 20, an irradiation unit 30, and a control device 40. The moving unit 20 in the present embodiment corresponds to an example of the "moving means" in the present embodiment, the irradiation unit 30 in the present embodiment corresponds to an example of the "irradiating means" in the present embodiment, and the control device in the present embodiment. 40 corresponds to an example of the "control means" in the present embodiment.

The stage 10 is a table on which the substrate 50 to be exposed is placed and holds the substrate 50. The stage 10 includes a holding plate 11 that holds the substrate 50, and legs 12 that support the holding plate 11. Although not particularly shown, a suction mechanism for sucking and holding the substrate 50 is embedded in the holding plate 11, and the suction mechanism makes it possible to fix the substrate 50 to the holding plate 11. In the present embodiment, the suction mechanism is embedded in the holding plate 11, but the suction mechanism is not limited to this, and the suction mechanism may be arranged between the holding plate 11 and the substrate 50.

The moving unit 20 is a unit that moves the irradiation unit 30 in the horizontal direction (XY direction in the figure) and the vertical direction (Z direction in the figure). In the present embodiment, the moving unit 20 moves (scans) the irradiation unit 30 along the pattern to be exposed on the surface of the substrate 50. That is, in the exposure apparatus 1 of the present embodiment, the vector scanning method is adopted as the scanning method. The scanning method of the exposure apparatus 1 is not limited to the vector scan, and may be, for example, a raster scan method or the like.

As shown in FIG. 2, the moving unit 20 includes a Y-axis moving mechanism 21, an X-axis moving mechanism 22, and a Z-axis moving mechanism 23.

The Y-axis moving mechanism 21 is a mechanism for moving the X-axis moving mechanism 22 in the Y direction, and includes a pair of Y-axis rails 211, a gantry 212, a Y-axis actuator 213, and a Y-axis sensor 214. ..

The pair of Y-axis rails 211 are fixed on the stage 10 along the Y direction. The gantry 212 is slidably provided on the Y-axis rail 211. The gantry 212 has a pair of columnar support portions 212a provided on the Y-axis rail 211 and a connecting portion 212b connecting the pair of support portions 212a.

The Y-axis actuator 213 can move (slide) the gantry 212, and the Y-axis sensor 214 can detect the position of the gantry 212. Although not particularly limited, an electric motor provided with a ball screw mechanism or the like can be exemplified as an example of the Y-axis actuator 213, and a rotary encoder, a linear encoder or the like can be exemplified as an example of the Y-axis sensor 214. ..

The X-axis moving mechanism 22 is a mechanism for moving the Z-axis moving mechanism 23 in the X direction, and is provided at the connecting portion 212b of the gantry 212. The X-axis moving mechanism 22 includes an X-axis rail 221, an X-axis stage 222, an X-axis actuator 223, and an X-axis sensor 224.

The X-axis rail 221 is fixed to the connecting portion 212b along the X direction. The X-axis stage 222 is slidably provided on the X-axis rail 221. The X-axis actuator 223 can move (slide) the X-axis stage 222, and the X-axis sensor 224 can detect the position of the X-axis stage 222. Although not particularly limited, an actuator similar to the Y-axis actuator 213 can be used as the X-axis actuator 223, and a sensor similar to the Y-axis sensor 214 can be used as the X-axis sensor 224.

The Z-axis moving mechanism 23 is provided on the X-axis stage 222, and includes a Z-axis rail 231, a Z-axis actuator 233, and a Z-axis sensor 234.

The Z-axis rail 231 is fixed on the X-axis stage 222 along the Z direction. The irradiation unit 30 is slidably provided on the Z-axis rail 231. The Z-axis actuator 233 can move (slide) the irradiation unit 30, and the Z-axis sensor 234 can detect the position of the irradiation unit 30. Although not particularly limited, an actuator similar to the Y-axis actuator 213 can be used as the Z-axis actuator 233, and a sensor similar to the Y-axis sensor 214 can be used as the Z-axis sensor 234.

Further, the moving unit 20 of the present embodiment has a focusing function of the pulsed laser light L from the irradiation unit 30. The exposure device 1 has a detection unit (not shown) that detects the in-focus state of the pulsed laser beam L, and the moving unit 20 moves the focal position of the condenser lens 33 based on the detection result of the detection unit. Is moved in the Z-axis direction so that the light is aligned on the surface of the substrate 50.

In the present embodiment, the substrate 50 is moved relative to the irradiation unit 30 by fixing the stage 10 and moving the irradiation unit 30 by the moving unit 20, but the present embodiment is not particularly limited to this. The substrate 50 may be moved relative to the irradiation unit 30 by making the holding plate 11 of the stage 10 movable, fixing the irradiation unit 30 and moving the substrate 50 in the XYZ direction. Alternatively, the substrate 50 may be moved relative to the irradiation unit 30 by making both the holding plate 11 of the stage 10 and the irradiation unit 30 movable. Further, by interposing a mirror between the irradiation unit 30 and the stage 10 and reflecting the pulsed laser light L while driving the mirror, the pulsed laser light L is moved (scanned) along the pattern to be exposed. You may let me.

As shown in FIG. 2, the irradiation unit 30 includes a laser light source 31, a collimator lens 32, and a condenser lens 33. The laser light source 31 intermittently emits pulsed laser light L capable of exposing the resist material forming the resist layer 51 to light. The output of the pulsed laser beam L is not particularly limited, but can be 0.1 mW or more and 10 W or less.

_{When the pulse signal SP} is input from the control device 40, the laser light source 31 emits the pulse laser light L with a constant output. The laser light source 31 is not particularly limited, but a semiconductor laser (laser diode) or the like can be used.

Further, the irradiation unit 30 includes a half mirror 34, a condenser lens 35, and a light receiving unit 36 in order to detect the pulse width of the pulsed laser beam L.

The laser light source 31, the collimator lens 32, the condenser lens 33, the half mirror 34, the condenser lens 35, and the light receiving unit 36 are fixed to the housing 37 (see FIG. 1) of the irradiation unit 30.

The exposure apparatus 1 draws a desired pattern on the resist layer 51 by intermittently irradiating the surface of the substrate 50 with pulsed laser light L while moving the irradiation unit 30 relative to the substrate 50 by the moving unit 20. To do. At this time, the pulsed laser light L emitted from the laser light source 31 is made into parallel light by the collimator lens 32. The pulsed laser beam L made into parallel light is branched at the half mirror 34. The pulsed laser light L transmitted through the half mirror 34 is condensed by the condenser lens 33 and imaged on the surface of the substrate 50. On the other hand, the pulsed laser light Lr reflected by the half mirror 34 passes through the condenser lens 35 and is incident on the light receiving unit 36.

The control device 40 is a microcomputer including a CPU, a ROM, a RAM, an A / D converter, an input / output interface, and the like. As shown in FIG. 3, the control device 40 functionally includes a drive control unit 41, a calculation unit 42, and a laser control unit 43.

The drive control unit 41 controls the Y-axis actuator 213, the X-axis actuator 223, and the Z-axis actuator 233 of the moving unit 20. By the drive control unit 41, the irradiation unit 30 moves horizontally in the XY direction and at the same time moves vertically in the Z direction. That is, the irradiation unit 30 adjusts the relative distance from the resist layer 51 while scanning on the resist layer 51.

The drive control unit 41 outputs the X-axis control signal S ₁ to the X-axis actuator 223, outputs the Y-axis control signal S ₂ to the Y-axis actuator 213, and outputs the Z-axis control signal S ₃ to the Z-axis actuator 233. To do. The drive of the X-axis actuator 223 and the Y-axis actuator 213 is controlled based on a desired drawing pattern.

The drive of the Z-axis actuator 233 is controlled so that the pulsed laser beam L is focused on the surface of the resist layer 51. The Z-axis sensor 234 _{outputs the movement distance L Z} along the Z direction to the drive control unit 41, and the drive control unit 41 uses the movement distance L _Z for control for focusing.

The calculation unit 42 calculates the horizontal movement distance L _H of the irradiation unit 30 and the horizontal movement speed v _{H of the} irradiation unit 30. Then, the calculation unit 42 outputs the calculated movement distance L _H and movement speed v _H to the laser control unit 43.

In the present embodiment, the X-axis sensor 224 _{inputs the moving distance L x} along the X direction of the irradiation unit 30 to the calculation unit 42, while moving from the Y-axis sensor 214 along the Y direction of the irradiation unit 30. inputting a distance _{L y} in the calculation unit 42.

Calculation unit 42, based on the moving distance _L x, _{L y,} calculates the moving distance _{L H} in the horizontal direction of the irradiation unit 30, the moving speed _{v H} in the horizontal direction of the irradiation unit 30, a. For example, the moving distance L _H is calculated by calculating (L _x ² + _Ly ² ) ^1/2. Moving velocity _{v H} is calculated by one example, dividing _{L H} at time ^{_{t ((L x 2 + L}} y 2) 1/2 / t). Alternatively, the moving distance L _H may be calculated by differentiating L _{H with respect to time t.} The Y-axis sensor 214, the X-axis sensor 224, and the calculation unit 42 in the present embodiment correspond to an example of the "detection means" in the present invention. Moving velocity v _H in the horizontal direction in the present embodiment corresponds to an example of "moving speed of the pulsed laser beam on the workpiece" and "relative speed with respect to the irradiation means of the workpiece" in the present invention.

The laser control unit 43 controls the laser light source 31. Specifically, the laser control unit 43 controls the interval at which the pulsed laser beam L of the laser light source 31 is emitted and the pulse width of the pulsed laser beam L.

In the present embodiment, the laser control unit 43, each time the irradiation unit 30 moves a certain distance L _const horizontally, and outputs a pulse signal S _P to the irradiation unit 30, a pulse laser beam L having a constant output Control to emit.

The laser control unit 43, according to the moving speed v _H input from the operation unit 42 controls the irradiation unit 30 to change the pulse pulse width of the laser beam L (the pulse on-time of) W _P. In the present embodiment, the laser control unit 43, the moving velocity _v H (mm / sec) is slow (small) enough, to control the laser light source 31 so as to increase the pulse width _{W P} (.mu.sec). However, the pulse width W _P is changed so as not to exceed the transit time of a constant distance L _const (μm) when the moving speed v _{H becomes the maximum.}

Specifically, in advance, respectively determined the optimum pulse width W _P for each moving speed v _H of the predetermined range, and a correspondence table of the pulse width W _P with respect to the moving velocity v _H, the laser control unit 43 Save it. The laser control unit 43 selects the pulse width W _P corresponding to the moving velocity v _H input from the correspondence table, emit a pulse laser beam L having a pulse width W _P selected in the laser light source 31. Although not particularly limited, the pulse width can be modulated by a laser driver or the like.

Incidentally, the method of determining the value of the pulse width W _P is not limited only to the method using the correspondence table described above. For example, it is possible to use a function that moving velocity v as _H is smaller pulse width W _P increases. This function may be, for example, performs a calculation of multiplying the variable that is inversely proportional to the moving velocity v _H to the current pulse width W _P, pulsed laser light with this calculated value by the function, is then emitted L of may be set to the pulse width W _P.

Further, as a pulse width control method executed by the laser control unit 43, for example, feedback control can be exemplified. In the present embodiment, the light receiving unit 36 detects the pulse width of the pulse laser light L, and the difference between the detected pulse width and the pulse width set by the laser control unit 43 is used as the pulse laser light L to be emitted next. Feedback is given to make corrections.

In the present embodiment, it is preferable to set _{the lap ratio RL} (%) of the pulsed laser beam L in the range of 50% or more and 90% or less (50% ≤ _{RL ≤ 90%).} In the present embodiment, the laser control unit 43 can control the laser light source 31 of the irradiation unit 30 so that the _{lap ratio RL (%) is within the above range.} For example, the lap rate _RL can be set to 80%.

FIG. 4 is an explanatory diagram showing the definition of the lap ratio. The lap ratio _RL referred to here is a value indicating the degree of overlap between the irradiated regions at the moment when the individual pulse laser light (single pulse laser light) of the pulse laser light L reaches the surface of the resist layer 51. .. Such an irradiated region can be assumed to be a circle whose diameter is the focused diameter of each pulsed laser beam. In the present embodiment, the irradiation shape of the pulsed laser beam L on the irradiated area is a circle, but the irradiation shape is not limited to this, and the irradiation shape may be an ellipse or a polygon.

In FIG. 4, P _n is the center point of the irradiated area C _{n , P n + 1} is the center point of the irradiated area C _{n + 1} , D is _{the diameter of the irradiated area C n} and the irradiated area C _{n + 1} , and P is the center point P _{n + 1.} It is the distance between the center point P _{n + 1} and the center point P n + 1 (inter-center distance). Further, l is a virtual straight line passing through the _{center point P n} and the center point P _{n + 1,} and X is the length of the virtual straight line l in the region where the _{irradiated region C n} and the irradiated region C _{n + 1 overlap (in other words,).} , The distance from the left end of the irradiated area C _{n + 1} to the right end of the _{irradiated area C n).}

Specifically, in the present embodiment, the lap ratio _RL can be defined as the following equation (1). Here, the shape and the irradiation regions C _{n + 1} the shape of the irradiated region C _n are the circle equal in diameter to each other, X in formula (1), the diameter D and the center as the following equation (2) It is the difference of the distance P.
_RL = X / D ... (1)
X = DP ... (2)

By setting the wrap ratio _RL to 50% or more, it is possible to more reliably irradiate the surface of the resist layer 51 with a sufficient amount of light. By setting the lap ratio _RL to 90% or less, it is possible to further suppress that the integrated exposure amount becomes locally large. Therefore, _{by controlling the lap ratio RL} within the above range, the variation in the line width of the pattern can be further suppressed.

Next, an exposure method (processing method) of the resist layer 51 using the exposure apparatus 1 as described above will be described. Figure 5 is a graph illustrating the moving velocity v _H of the illumination unit 30 in the embodiment of the present invention, the relationship between the pulse width W _P of the pulse laser beam. Figure 5 (a) (upper graph) is a graph showing the relationship between the moving velocity v _H and the elapsed time t of the illumination unit 30, FIG. 5 (b) (lower graph) is a pulse width of the pulse laser beam W _P and the elapsed time is a graph showing the relationship between the t. In each graph of FIG. 5, P denotes the output of the pulse laser light L, W _P represents the pulse width, W _f represents the pulse off time, T is representing the pulse period .. Here, W _P , W _f , and T are variables. Incidentally, FIG. 5 (b) is a diagram for explaining the control of the pulse width W _p of the embodiment easily, period T, the pulse width W _p, accurately represents the value of such off-time W _f Not at all.

In Figure 5, when the irradiation unit 30 after the constant velocity movement, once decelerated, return to constant speed movement again, describes a change in the pulse width W _P. In FIG. 5, the speed during constant velocity movement is v _H1 , and the speed during deceleration and acceleration is v _H2 . _{The speed v H1} during constant velocity movement in the present embodiment corresponds to an example of the “first moving speed” in the present invention, and the speed v _H2 during deceleration and acceleration in the present embodiment corresponds to the “second moving speed” in the present invention. It corresponds to an example of "moving speed".

As shown in FIG. 5, when the irradiation unit 30 is moving at a speed v _H1 constant (usually) a laser control unit 43 controls the pulse width W _P constant. On the other hand, in a section where the irradiation unit 30 is decelerated, the laser control unit 43 increases the pulse width W _P according to the decrease of the moving speed v _H2. Conversely, in the section where the irradiation unit 30 is accelerated, the laser control unit 43, thereby reducing the pulse width W _P in accordance with an increase in the moving velocity v _H2.

When the irradiation unit 30 is _{moving at a constant (normal) speed v H1} , the laser control unit 43 has a duty ratio DR (%) of 40% or more and 60% or less (40% ≤ DR ≤ 60%). The laser light source 31 of the irradiation unit 30 is controlled so as to be. Here, the duty ratio means the ratio of the pulse width (μsec) to the one-period T (μsec) when the pulse wave is periodically emitted, and is expressed by the following equation (3). In the following equation (3), W _P represents the pulse width, T is represents the pulse period. That, T is the sum of the pulse ON time _{W P} and off time _{W f (T = W P +} W f). Also, off-time W _f is a variable that varies with changes in the pulse width W _{P.
DR = W P / T ... (} 3)

When the irradiation unit 30 is moving at a relatively high speed as in this case, by setting the duty ratio DR to 40% or more, it is assumed that the irradiation unit 30 moves at a high speed and the pulse becomes dull. (That is, even if there is a delay in the rise of the pulsed laser beam L), the surface of the resist layer 51 can be more reliably irradiated with a sufficient amount of light. Further, by setting the duty ratio DR to 60% or less, even when the irradiation unit 30 moves at high speed, it becomes difficult for the pulse laser light L to be continuously irradiated (that is, the time during which the pulse laser light L is turned off). It is possible to more reliably secure the above and separate the individual pulsed laser beams), so that it is possible to further suppress the local increase in the integrated exposure amount.

On the other hand, when the moving speed of the irradiation unit 30 is small (when the moving speed in FIG. 5 is v _H2 ), the irradiation interval (cycle) of the pulsed laser beam L becomes long, so that the duty ratio D is 40. It will be less than%. In the present embodiment, such a case is to increase the pulse width W _P than when the moving speed of the irradiation unit 30 is v _H1.

Consequently, the laser controller 43, the integrated exposure amount when the moving speed is _{v H1} (J / cm ²⁾ is integrated exposure amount when the moving speed is smaller _{v H2} than _{v H1} (J / The irradiation unit 30 is controlled so as to be smaller than ^{cm 2).}

Examples of the case where the irradiation unit 30 moves at a constant velocity include a case where a straight line portion of the drawing pattern is drawn. That is, when the irradiation unit 30 is in linear motion, the irradiation unit 30 moves at a constant velocity. On the other hand, examples of the case where the irradiation unit 30 decelerates and accelerates include a case where the drawing pattern includes a polygonal line or a curved line. In this case, since the irradiation unit 30 needs to change direction or move in a curve in the horizontal plane, local deceleration and acceleration tend to occur when changing the direction or moving in a curve. ..

As described above, when the irradiation unit 30 is locally decelerated and the pulse width of the pulsed laser light is kept constant, the chemically amplified resist material may not sufficiently react. If the resist material does not react sufficiently, the desired line width cannot be obtained in some patterns, so that the line width varies.

The chemical reaction of the resist material in this case will be described with reference to FIGS. 6 and 7. FIG. 6 is an explanatory diagram of a chemical reaction of the resist material when the irradiation unit is moved at a _{normal moving speed (for example, the above-mentioned constant speed v H2} ) in an exposure in which the pulse width of the pulsed laser beam is constant. FIG. 7 is an explanatory diagram of the chemical reaction of the resist material when the moving speed of the irradiation unit is slower than that in the case of FIG. 6 in the exposure of FIG. 6 (for example, when the moving speed is the above moving speed v _H2). Is. In either case, the pulsed laser beam is controlled to be emitted every time the vehicle travels a certain distance.

The chemically amplified resist can be dissolved in an alkaline solution during development by diffusing the acid generated during irradiation with pulsed laser light even in places not exposed to light. When the moving speed of the irradiation unit is high (normal case), the time for moving a certain distance is short, and the irradiation interval (cycle) of the pulsed laser beam is also short. Therefore, as shown in FIG. 6, since the pulsed laser light irradiates the resist material at short intervals, a chain reaction proceeds in the process of acid generation, and an effect of amplifying the solubility in an alkaline solution can be obtained. As a result, it is possible to sufficiently secure a region that dissolves in the alkaline solution during development.

On the other hand, when the moving speed of the irradiation unit is slow, the time for moving a certain distance increases, and the irradiation interval (cycle) of the pulsed laser light becomes long. Therefore, as shown in FIG. 7, a chain reaction does not occur in the acid generation process and the reaction becomes sporadic, so that the above-mentioned amplification action does not occur and the developed pattern dissolves in the alkaline solution. The area is reduced. As a result, there is a portion where the line width is locally narrowed in the developed pattern.

This phenomenon is particularly remarkable when the line width of the target developed pattern is 10 μm or less. In this case, the focused diameter of the pulsed laser light approaches the molecular size, the probability of the light hitting the photopolymerization initiator when the laser is irradiated decreases, and a chain reaction when the acid is released occurs in particular. This is because it becomes difficult.

Further, even when a continuous oscillation method (CW method) laser is used instead of the pulsed laser light, overexposure occurs when the irradiation unit is decelerated, so that the line width is locally generated in the developed pattern. There will be a thickened part.

On the other hand, in the present embodiment, the laser control unit 43 is said to have more exposure than the integrated exposure amount in the section _{where the moving speed v H} of the irradiation unit 30 is high (the section where the moving speed v _{H1 in FIG. 5).} The integrated exposure amount is controlled to be large in the section where the moving speed v _H is slow (the section where the moving speed v _{H2 in FIG. 5).} Thus, also in the movement speed v _H is small section of the irradiation unit 30, since the resist material of the resist layer 51 be continuously reacted becomes possible, it is possible to suppress variations in line width of the pattern. In particular, even when the line width of the pattern is set to 10 μm or less, the variation in the line width can be suppressed.

It should be noted that the embodiments described above are described for facilitating the understanding of the present invention, and are not described for limiting the present invention. Therefore, each element disclosed in the above-described embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

For example, in the above embodiment, the exposure device 1 is illustrated as an example of the laser irradiation device, but the present invention is not limited to this, and other processing devices may be used. For example, it may be used in an ultraviolet irradiation device used for ultraviolet curing of a material and a processing device such as a 3D printer.

Further, in the above embodiment, the pulsed laser beam L is focused by moving the irradiation unit 30 in the Z-axis direction, but the present invention is not limited to this. For example, the substrate 50 may be moved in the Z-axis direction. Alternatively, only the condenser lens 33 may be moved in the Z-axis direction.

Further, in the above embodiment, the pulse width is detected by the light receiving unit 36, but the present invention is not limited to this, and the half mirror 34 may be provided with a mechanism capable of detecting the pulse width. Further, in the above embodiment, the light receiving unit 36 detects the pulse width based on the pulsed laser light L branched by the half mirror 34, but the present invention is not limited to this, and the resist layer 51 of the pulsed laser light L is not limited to this. The pulse width of the pulse laser beam L may be detected based on the reflected light on the surface.

1 ... Exposure device 10 ... Stage 11 ... Holding plate 12 ... Legs 20 ... Moving unit 21 ... Y-axis moving mechanism
211 ... A pair of Y-axis rails
212 ... Gantry
212a ... Support
212b ... Connecting part
213 ... Y-axis actuator
214 ... Y-axis sensor 22 ... X-axis movement mechanism
221 ... X-axis rail
222 ... X-axis stage
223 ... X-axis actuator
224 ... X-axis sensor 23 ... Z-axis movement mechanism
231 ... Z-axis rail
233 ... Z-axis actuator
234 ... Z-axis sensor 30 ... Irradiation unit 31 ... Laser light source 32 ... Collimator lens 33 ... Condensing lens 34 ... Half mirror 35 ... Condensing lens 36 ... Light receiving unit 37 ... Housing 40 ... Control device 41 ... Drive control unit 42 ... Calculation unit 43 ... Laser control unit 50 ... Substrate 51 ... Resist layer L ... Pulse laser light

Claims (7)

Irradiation means for irradiating the work with pulsed laser light,
A moving means for moving the pulsed laser beam on the work, and
A detection means for detecting the moving speed of the pulsed laser beam on the work, and
A control means for controlling the irradiation means and the moving means is provided.
The control means
The irradiation means is controlled so as to intermittently irradiate the pulsed laser beam at regular movement distances, and the irradiation means is controlled.
A laser irradiation device that controls the irradiation means so that the pulse width of the pulsed laser light increases as the moving speed becomes slower. The laser irradiation device according to claim 1.
The control means has a second movement speed when the movement speed is slower than the first movement speed than the first integrated exposure amount when the movement speed is the first movement speed. A laser irradiation device that controls the irradiation means so that the integrated exposure amount of 2 becomes large. The laser irradiation device according to claim 2.
When the moving speed is the first moving speed, the duty ratio is 40% or more and 60% or less.
A laser irradiation device having a duty ratio of less than 40% when the moving speed is the second moving speed. The laser irradiation device according to claim 1 or 2.
The control means is a laser irradiation device that controls the irradiation means so that the lap ratio of the pulsed laser light is 50% or more and 90% or less. The laser irradiation device according to any one of claims 1 to 4.
The work includes a resin layer containing a photopolymerization initiator.
The irradiation means is a laser irradiation device that irradiates the resin layer with the pulsed laser light. The laser irradiation device according to any one of claims 1 to 5.
A laser irradiation device having a line width of 10 μm or less of a pattern drawn on the resin layer by the pulsed laser beam. A method for manufacturing a resin molded product, which irradiates a resin portion with a pulsed laser beam and moves the resin portion on the resin portion.
While intermittently irradiating the pulsed laser beam at regular movement distances,
A method for producing a resin molded body in which the pulse width of the pulsed laser light is increased as the moving speed of the pulsed laser light on the resin portion is slower.

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