TW202111440A - Exposure method and method for establishing an exposure energy setting and imaging system - Google Patents

Abstract

The present invention disclosed an exposure method, the method includes steps a to f, wherein step a includes a power supply setting value for adjusting an imaging system and a light source, step b includes the light source to emit an exposure light according to the adjusted power supply setting value, step c includes the actual exposure energy of the exposure light measured, step d includes determining whether the measured actual exposure energy is equal to a target exposure energy. Wherein, if the result is yes, step e will be executed, but if the result is no, steps a to d will be repeated. Step e includes the adjusted power supply setting value of step a as the actual power supply value of the light source, step f includes the light source exposing a light blocking layer of the exposed substrate according to the actual power supply value recorded in step e.

Description

Exposure method, method for establishing an exposure energy setting table and exposure machine

The present invention relates to an exposure machine, and particularly refers to an exposure method, a method of establishing an exposure energy setting table, and an exposure machine using the aforementioned method.

The use of laser diodes as exposure light sources has become increasingly common in the field of exposure machines. This type of exposure machine usually has a setting unit for an operator to set a power supply setting value according to demand. The power supply setting value is the current value or voltage value supplied to the laser diode. Under the same exposure time, increasing or decreasing the current value or voltage value supplied to the laser diode will correspondingly change the exposure energy of the exposure light emitted by the laser diode.

Once the operator sets a power supply setting value, each laser diode of the exposure machine will emit exposure light according to the power supply setting. Under ideal conditions, the exposure energy of the exposure light emitted by each laser diode should be the same as the exposure energy corresponding to the power supply setting. However, even for the same batch of laser diodes, the current There is still no guarantee that their characteristics are exactly the same. In fact, the characteristics of each laser diode are not the same, and as the use time increases, the characteristics of each laser diode will change again. As a result, the actual exposure energy of the exposure light emitted by each laser diode according to the same power supply setting value is different, which will cause the exposure machine to have the problem of uneven exposure, which needs to be improved urgently.

In response to the above problems, Taiwan Patent No. 201445260 discloses an exposure energy correction method. In this method, multiple light energy sensing units are used to sense the projected light energy of multiple exposure devices one-to-one, and one processing unit It is used to calculate the minimum value of the projected light energy, and a memory unit is used to record the minimum value. The processing unit also corrects the projected light energy of the exposure devices by adjusting the amount of power supply, and detects whether the projected light energy of the exposure devices is the same after being calibrated. If there are differences, continue to perform the aforementioned adjustment and detection until the The projection energy of these exposure devices are all equal and less than or equal to the minimum value.

Taiwan Patent No. M409455 discloses an exposure energy adjustment system. In this system, a measuring plate with multiple light energy sensors is used to measure the exposure energy intensity at different positions in an exposure area. The energy intensity measured by each light energy sensor calculates the adjustment information of the relevant optical element, and the position of the relevant optical element is adjusted manually or automatically according to the adjustment information.

In addition, Taiwan Patent No. M518777 discloses a UV energy adjustment device for an exposure machine. In this device, a UV energy sensor is used to sense the irradiation energy of the UV-LED at each position, and the UV- The irradiation energy of the LED is transmitted to a UV energy adjustment part, after which the UV energy adjustment part adjusts the irradiation energy of all UV-LEDs to be the same, for example, all is adjusted to the lowest of the irradiation energies of the UV-LEDs, or All are adjusted to the specified irradiation energy.

The present invention provides a new exposure method suitable for an exposure machine having at least one exposure light source, and the method includes steps a to f. First, as in step a, adjust the power supply setting value of the exposure light source. Then, in step b, the exposure light source is made to emit an exposure light according to the adjusted power supply setting value. Then, as in step c, measure the actual exposure energy of the exposure light. In step d, it is determined whether the measured actual exposure energy is equal to a target exposure energy, which is determined according to the material characteristics of a photoresist layer of a substrate to be exposed. If the judgment result is "Yes", go to step e, and if the judgment result is "No", repeat steps a to d. Wherein, step e includes recording the power supply setting value adjusted in step a as the actual power supply setting value of the exposure light source. Finally, in step f, the exposure light source is made to expose the photoresist layer of the substrate to be exposed according to the actual power supply setting value recorded in step e.

In one embodiment, the power supply setting value of the exposure light source determines the current value or the voltage value supplied to the exposure light source.

In one embodiment, the exposure light emitted by the exposure light source is received by an exposure energy measuring device, which can measure the exposure energy of the exposure light.

The present invention also provides a method for establishing an exposure energy setting table. The method includes performing the above steps a to e for each exposure light source of an exposure machine, so as to obtain the actual power supply setting value of each exposure light source to form the exposure energy Setting table.

The present invention also provides a new exposure machine, which includes a plurality of exposure light sources, and records the actual power supply setting value of each exposure light source. The actual power supply setting value of each exposure light source is obtained from the above steps a to e.

The present invention also provides a new exposure machine, which includes multiple exposure light sources, and enables each exposure light source to emit an exposure light according to its own actual power supply setting value, and the actual power supply setting value of each exposure light source is obtained from the request item Steps a to e described in 1.

Compared with the prior art, the exposure machine of the present invention has the advantage of uniform exposure energy, and the actual exposure energy of each exposure light source is the best or ideal exposure energy desired for the photoresist layer of the substrate to be exposed.

FIG. 1 shows a flowchart of an embodiment of the exposure method of the present invention, which is suitable for an exposure machine. In this embodiment, as shown in FIG. 2, the exposure machine can be a maskless exposure machine, but it can also be other types of exposure machines. In any case, the exposure machine includes a plurality of exposure light sources 1 and an optical lens group 2. Each exposure light source 1 can be a laser diode or a light emitting diode, the wavelength of which depends on the material properties of a photoresist layer 41 on the surface of a substrate 4 to be exposed, such as a 405 nm blue laser diode Body, or ultraviolet light emitting diode, but not limited to this. The photoresist layer 41 can be dry or wet, and this embodiment is a photo resist dry film commonly used in printed circuit board manufacturing.

As shown in FIG. 2 again, the optical lens group 2 is located under the exposure light sources 1, and the exposure light 11 emitted by each exposure light source 1 is projected to the photoresist layer 41 of the substrate 4 to be exposed through the optical lens group 2, and At the same time, the substrate 4 to be exposed is carried by a moving stage 40 and advances in a predetermined direction A. Wherein, the optical lens group 2 includes a rotating polyhedral beam 21 having a plurality of facets 211, and the rotating polyhedral beam 21 is driven to rotate by a driving device (not shown in the figure), thereby changing the exposure light 11 on the photoresist layer 41 The location of the drop point (see Figures 3 to 5). The driving device includes a motor (such as a servo motor) and its transmission components. In this embodiment, the long axis of the rotating polyhedron 21 is perpendicular to the predetermined direction A, but this is only for the convenience of the illustrated example. In fact, the rotating polyhedral 21 is preferably arranged obliquely, that is, The long axis of the rotating polyhedral beam 21 is inclined to the predetermined direction A.

The optical lens group 2 preferably further includes a plurality of focusing lenses for focusing the exposure light 11 to the photoresist layer 41, a compensation lens for correcting aberrations, or other lenses required to improve imaging quality. For this part, please refer to Taiwan I666526 patent.

In this embodiment, the rotating polyhedral beam 21 is a penetrating multi-faceted beam. As shown in FIGS. 3 to 5, the exposure light 11 enters from one of the facets 211 of the rotating polyhedron 21, and is emitted from the other facet 211 on the opposite side, and then is projected to the photoresist layer 41. Among them, the rotating polyhedral ridge 21 rotates counterclockwise, the rotating polyhedral ridge 21 of FIG. 3 rotates 15 degrees to reach the position shown in FIG. 4, and the rotating polyhedral ridge 21 of FIG. 4 continues to rotate 15 degrees to reach the position shown in FIG. 5. During this process, the exposure light 11 changes its landing point on the photoresist layer 41 along with the rotation of the rotating polyhedron 21.

For the convenience of description, only one of the above-mentioned exposure light sources 1 is taken as an example below. As shown in FIG. 1, the exposure method of the present invention includes the following steps a to f. First, as in step a, the power supply setting value of the exposure light source 1 is adjusted so as to change the exposure energy of the exposure light 11 emitted by the exposure light source 1. The power supply setting value of the exposure light source 1 usually refers to the current value or the voltage value. Once the power supply setting value is set, it means that the exposure light source 1 will obtain the power supply corresponding to the power supply setting value, and will emit a power supply under this power supply. Exposure light 11. Under the same exposure time, increasing or decreasing the current or voltage supplied to the exposure light source 1 will correspondingly change the exposure energy of the exposure light 11 emitted by the exposure light source 1.

An operator can determine a target exposure energy D1 according to the material properties of the photoresist layer 41 on the substrate 4 to be exposed to be exposed, and then adjust the power supply setting value of the exposure light source 1 with the target exposure energy D1 as the target. The target exposure energy D1 refers to the optimal or ideal exposure energy required by the photoresist layer 41. The material properties of the photoresist layer 4 can be known from the material parameters provided by the photoresist material supplier. The photoresist material supplied by different manufacturers requires different optimal or ideal exposure energy.

Then, in step b, the exposure light source 1 is caused to emit an exposure light 11 according to the adjusted power supply setting value. Then, as in step c, the actual exposure energy D2 of the exposure light 11 is measured. In this way, an exposure energy measuring device (not shown in the figure) can be used to receive the exposure light 11 so as to measure the actual exposure energy D2 of the exposure light 11. In this embodiment, the exposure energy measuring device may be a laser power sensor (Laser Power Sensor) or a laser power meter (Laser Power Meter).

After the measurement is completed, in step d, it is judged whether the measured actual exposure energy D2 is equal to the target exposure energy D1. If the judgment result is "Yes", that is, D2=D1, then step e is executed, that is, step a The adjusted power supply setting value is recorded as the actual power supply setting value of the exposure light source 1. However, if the judgment result is "No", that is, D2>D1 or D2>D1, repeat steps a to d. In step a, if D2>D1, the power supply setting value is reduced to reduce the energy of the exposure light 11 emitted by the exposure light source 1. However, if D2>D1, the power supply setting value is increased to increase the exposure light source 1 emission The energy of the exposure light 11.

Finally, in step f, the exposure light source 1 is made to expose the photoresist layer 41 of the substrate 4 to be exposed according to the actual power supply setting value recorded in step e.

From the above description, after one or more adjustments and measurements, the energy of the exposure light 11 emitted by the exposure light source 1 according to the adjusted power supply setting value, that is, the actual exposure energy D2 will be equal to (or roughly Equal to) the target exposure energy D1. At this time, the adjusted power supply setting value is recorded as the actual power supply setting value of the exposure light source 1. In the case of multiple exposure light sources 1, each exposure light source 1 will obtain its own actual power supply setting value after the above steps. At this time, the exposure machine of the present invention will set the actual power supply setting value of each exposure light source 1 Record it, for example, in an exposure energy setting table for use in subsequent actual exposure operations.

Since each exposure light source 1 of the exposure machine of the present invention can obtain its own actual power supply setting value according to the above steps, and expose the photoresist layer 41 of the substrate 4 to be exposed according to its own actual power supply setting value, and every time An exposure light source 1 adjusts its power supply setting value with the above-mentioned target exposure energy D1 as the target, and finally is adjusted to make its actual exposure energy D2 equal to (or roughly equal to) the target exposure energy D1, so When each exposure light source 1 exposes the photoresist layer 41 according to the actual power supply setting value finally adjusted to, the actual exposure energy D2 of the exposure light 11 emitted by each exposure light source 1 at this time will be equal (or roughly Equal), and both are equal to (or roughly equal to) the target exposure energy D1, which means that the exposure machine of the present invention has the advantage of uniform exposure energy, and the actual exposure energy D2 of each of its exposure light sources 1 is the photoresist layer 41 The best or ideal exposure energy desired.

In addition, FIGS. 6 to 8 show that the exposure machine is changed to an optical lens set 2a. The optical lens set 2a includes a reflective rotating polyhedron 21a. The exposure light 11 is reflected to one of the facets 211a and then reflected to the lower photoresist. Layer 41, and the falling point of the exposure light 11 changes with the rotation of the rotating polyhedron 21a.

1: Exposure light source 11: Exposure light 2, 2a: Optical lens group 21, 21a: Rotating multi-faceted 稜鏡 211, 211a: facet 4: substrate to be exposed 41: photoresist layer 40: mobile carrier a～f: steps

Fig. 1 shows a flow chart of the exposure energy setting method of the present invention. Figure 2 shows a schematic diagram of the basic structure of the exposure machine of the present invention. Figures 3 to 5 show the schematic diagrams of the exposure action of the exposure machine (using the penetrating rotating multi-faceted 稜鏡 21). Figures 6 to 8 show the schematic diagrams of the exposure action of the exposure machine (which adopts the reflective rotating multi-faceted prism 21a).

a~f: steps

Claims (6)

An exposure method is suitable for an exposure machine having at least one exposure light source, and the method includes: a. Adjust the power supply setting value of the exposure light source; b. Order the exposure light source to emit an exposure light according to the adjusted power supply setting value; c. Measure the actual exposure energy of the exposure light; d. Determine whether the measured actual exposure energy is equal to a target exposure energy, which is determined according to the material characteristics of a photoresist layer of a substrate to be exposed; where, if the result of the judgment is "Yes", then Perform step e, if the judgment result is "No", repeat steps a to d; e. Record the power supply setting value adjusted in step a as the actual power supply setting value of the exposure light source; and f. Order the exposure light source to expose the photoresist layer of the substrate to be exposed according to the actual power supply setting value recorded in step e. The exposure method according to claim 1, wherein the power supply setting value of the exposure light source determines the current value or the voltage value supplied to the exposure light source. The exposure method according to claim 1, wherein the exposure light emitted by the exposure light source is received by an exposure energy measuring device, and the exposure energy measuring device can measure the exposure energy of the exposure light. A method for establishing an exposure energy setting table includes: Perform steps a to e as described in claim 1 for each exposure light source of an exposure machine to obtain the actual power supply setting value of each exposure light source to form the exposure energy setting table. An exposure machine includes a plurality of exposure light sources, and records the actual power supply setting value of each exposure light source. The actual power supply setting value of each exposure light source is obtained from steps a to e described in claim 1. An exposure machine includes a plurality of exposure light sources, and enables each exposure light source to emit an exposure light according to its own actual power supply setting value, and the actual power supply setting value of each exposure light source is obtained from steps a to as described in request item 1. e.

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