WO2007138884A1 - レーザパルス発生装置及び方法並びにレーザ加工装置及び方法 - Google Patents
レーザパルス発生装置及び方法並びにレーザ加工装置及び方法 Download PDFInfo
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- WO2007138884A1 WO2007138884A1 PCT/JP2007/060202 JP2007060202W WO2007138884A1 WO 2007138884 A1 WO2007138884 A1 WO 2007138884A1 JP 2007060202 W JP2007060202 W JP 2007060202W WO 2007138884 A1 WO2007138884 A1 WO 2007138884A1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/13—Stabilisation of laser output parameters, e.g. frequency or amplitude
- H01S3/131—Stabilisation of laser output parameters, e.g. frequency or amplitude by controlling the active medium, e.g. by controlling the processes or apparatus for excitation
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/11—Mode locking; Q-switching; Other giant-pulse techniques, e.g. cavity dumping
- H01S3/1123—Q-switching
- H01S3/117—Q-switching using intracavity acousto-optic devices
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/106—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity
- H01S3/108—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity using non-linear optical devices, e.g. exhibiting Brillouin or Raman scattering
- H01S3/109—Frequency multiplication, e.g. harmonic generation
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/13—Stabilisation of laser output parameters, e.g. frequency or amplitude
- H01S3/131—Stabilisation of laser output parameters, e.g. frequency or amplitude by controlling the active medium, e.g. by controlling the processes or apparatus for excitation
- H01S3/1312—Stabilisation of laser output parameters, e.g. frequency or amplitude by controlling the active medium, e.g. by controlling the processes or apparatus for excitation by controlling the optical pumping
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/09—Processes or apparatus for excitation, e.g. pumping
- H01S3/091—Processes or apparatus for excitation, e.g. pumping using optical pumping
- H01S3/094—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light
- H01S3/094076—Pulsed or modulated pumping
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/09—Processes or apparatus for excitation, e.g. pumping
- H01S3/091—Processes or apparatus for excitation, e.g. pumping using optical pumping
- H01S3/094—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light
- H01S3/0941—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a laser diode
- H01S3/09415—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a laser diode the pumping beam being parallel to the lasing mode of the pumped medium, e.g. end-pumping
Definitions
- the present invention relates to a processing apparatus using a laser oscillation device suitable for processing circuit components of a semiconductor device on a semiconductor wafer, and obtains a stable high output Q switch pulse even when the pulse repetition frequency is changed. An apparatus and method is obtained. Furthermore, a fine processing apparatus and method capable of always obtaining a stable output even at any irradiation timing are realized.
- Fig. 1 shows a pulse stabilization method in which the AOM is operated for each pulse, and uses a method in which the low output cannula generated after the oscillation of the Q switch pulse is removed by the AOM.
- a pumping light source 1 such as a semiconductor laser
- a laser oscillation pumping condensing unit 10 of a solid-state laser medium 5 Is released towards between this, a condensing optical system 3 such as a lens and a high reflecting mirror 4 that is highly reflective to the laser wavelength constituting the solid laser resonator and transparent to the excitation light wavelength are interposed.
- the other output mirror 7 of the laser resonator is installed on the side opposite to the high reflection mirror 4 of the laser medium 5. Between the laser medium 5 and the output mirror 7, there is a Q switch element 6 that is an acousto-optic switch element force. Installed.
- An operation control signal is emitted from the control unit 11 of the laser apparatus to the pumping light source driving unit 8, the Q switch driving unit 9, and the AOM driving unit 12 that controls the AOM 29 installed outside the laser resonator.
- AOM applies RF power to an ultrasonic transducer to create a Bragg diffraction cell and diffracts the passing beam. Therefore, when RF is applied to the cell from the driving unit 12, a part of the beam is separated by diffraction at the time of RF application.
- the laser pulse that propagates the RF power sound wave to the AOM diffraction cell and passes through the diffraction grating is collimated by the beam expander 15, travels to the reflector 16, is reflected, and is directed to the workpiece 20 and collected by the lens 18 As a result, the surface of the cleaning object 20 is focused and irradiated and processed.
- the workpiece 20 is precisely positioned and driven by the drive table 23.
- the drive is performed by the drive unit 21 via the control signal line 26 from the control unit 11 using a known technique.
- the laser output beam 30IR has a Q switch It includes a luster part 30MIR and a continuous output part 13SIR.
- the application timing of RF power RFD from the drive unit 12 to this AOM29 is as shown in Fig. 2 (d) after the end of the Q switch pulse 30MIR.
- Continuous oscillation part 13SIR oscillation and timing are inserted. Since the continuous oscillation part 13SIR is diffracted by the AOM 29, it is separated from the Q switch pulse 30MIR to obtain a beam 13SIR in another direction as shown in FIG.
- the continuous laser part 14 shows this. Separate the Q switch pulse part 30MIR and the continuous laser part 1 3SIR so that it does not point at the workpiece 20. Therefore, only the Q switch pulse 30MIR is irradiated to the workpiece 20, which contributes to the machining.
- AOM29 In such a conventional configuration, it is necessary to install an AOM 29 outside the oscillator and control the operation timing in synchronization with pulse oscillation. There is a loss due to AOM29, there is a loss of power. Using AOM29 has the disadvantages of increasing the cost of the equipment and requiring an installation site. In addition, when the laser beam wavelength changes, the AOM 29 needs to be optimized again, such as the installation angle and the need to change the antireflection film on the optical end face.
- a method of adjusting the number of distributions of the upper level of the laser oscillation such as a method of oscillating the Q switch pulse after the oscillation and a method of reducing the excitation intensity from the excitation light source before the Q switch pulse oscillation in advance.
- Patent Document 1 US Patent No. 4337442
- Patent Document 2 U.S. Pat.No. 5,018,152
- Patent Document 3 U.S. Pat.No. 5,291,505
- Patent Document 4 U.S. Pat.No. 5,339,323
- Patent Document 5 US Patent No. 5812569
- Patent Document 6 US Patent No. 5982790
- Patent Document 7 US Patent No. 6038241
- Patent Document 8 US Patent No. 6418154
- Patent Document 9 US Patent No. 6009110
- Patent Document 10 US Patent No. 6683893
- Patent Document 11 US Patent No. 6931035
- Patent Document 12 US Patent No. 6172325
- Patent Document 13 US Patent No. 5719372
- Patent Document 14 U.S. Pat.No. 4412330
- Patent Document 15 Special Publication 2002-518834
- the problem to be solved by the present invention is equalization of repeated Q-switch pulse output. That is, it is to provide a laser pulse generating apparatus and method capable of obtaining a stable Q-switched pulsed laser oscillation output that does not depend on the pulse repetition time interval, and laser processing using the same. It is to provide an apparatus and method.
- the present invention provides a Q switch element for suppressing laser oscillation by controlling a Q value of a laser medium, a laser resonator, and the laser resonator, and deexcitation of the laser medium.
- a laser oscillation suppression signal is applied to the laser medium by applying a laser oscillation suppression signal to the source, a means for operating the deexcitation source for a first predetermined time, and discharging stored energy from the laser medium, and a second predetermined time.
- the means for providing the laser medium excitation source and emitting the stored energy further includes means for reducing excitation intensity of the excitation source or stopping or blocking excitation. Further, the means for accumulating the energy further includes the laser. Means is provided for setting the level of the oscillation suppression signal to a level that does not have sufficient oscillation suppression capability. Further, the means for releasing the stored energy further includes means for setting the first predetermined time to zero or more.
- a laser medium a laser resonator, a Q switch element that suppresses laser oscillation by controlling a Q value of the laser resonator,
- Means for stopping a laser oscillation suppression signal to the Q switch element in order to obtain a Q switch laser pulse oscillation output Means for stopping a laser oscillation suppression signal to the Q switch element in order to obtain a Q switch laser pulse oscillation output.
- a laser medium a laser resonator, a Q switch element that suppresses laser oscillation by controlling a Q value of the laser resonator, and means for providing a modulated excitation signal to the laser medium;
- Means for storing a predetermined energy in the laser medium by applying a laser oscillation suppression signal to the Q switch element for a predetermined time, and a laser to the Q switch element to obtain a Q switch laser pulse oscillation output. And a means for stopping the oscillation suppression signal.
- a laser medium, a laser resonator, a Q switch element that suppresses laser oscillation by controlling a Q value of the laser resonator, and a laser oscillation suppression signal is printed on the Q switch element.
- the present invention is characterized in that a nonlinear optical element is further provided in the optical path of the Q-switch laser pulse.
- the laser processing device irradiates the processing target with the pulse output from these laser pulse generators, and the processing target is an electronic device such as a link wiring, capacitor, resistor, inductor on the semiconductor substrate.
- a display device such as a liquid crystal display device, an electroluminescence display device, or a plasma display device.
- the present invention includes a step of providing a Q switch element that suppresses laser oscillation by controlling the Q value of the laser medium, the laser resonator, and the laser resonator, and a deexcitation source of the laser medium;
- the de-excitation source is operated for a first predetermined time to release the laser medium force storage energy, and the second predetermined time is applied to apply a laser oscillation suppression signal to the Q switch element to store the predetermined energy in the laser medium.
- the excitation intensity to the laser medium is further reduced, or excitation is stopped or interrupted.
- the level of the laser oscillation suppression signal is set to a level that does not have sufficient oscillation suppression capability.
- the first predetermined time is zero or more.
- a step of providing a laser medium, a laser resonator, and a Q switch element that suppresses laser oscillation by controlling the Q value of the laser resonator, and a Q switch element having sufficient oscillation suppression capability for a predetermined time Applying a laser oscillation suppression signal of a signal level that does not have the step of accumulating a predetermined energy in the laser medium and obtaining the Q switch laser pulse oscillation output by stopping the laser oscillation suppression signal to the Q switch element It has a step.
- a step of providing a laser medium, a laser resonator, and a Q switch element that suppresses laser oscillation by controlling the Q value of the laser resonator, and a step of providing a modulated excitation signal to the laser medium Applying a laser oscillation suppression signal to the Q switch element for a predetermined period of time to store the predetermined energy in the laser medium, and stopping the laser oscillation suppression signal to the Q switch element causes the Q switch laser pulse oscillation And a step of obtaining an output.
- a step of providing a Q switch element for suppressing laser oscillation by controlling the Q value of the laser medium, the laser resonator, and the laser resonator, and suppressing the laser oscillation in the Q switch element By applying a damping signal and accumulating energy in the laser medium, and modulating the laser oscillation suppression signal depending on the previous pulse force generation interval, a loss corresponding to the generation interval from the previous pulse is reduced. And obtaining a Q-switch laser pulse oscillation output in a state of
- the present invention is characterized by further comprising a step of converting the Q-switch laser pulse into a harmonic and outputting the harmonic.
- the present invention also includes a laser carriage method having a step of irradiating a laser target generated by these laser pulse generation methods, and the target object is a link wiring, a capacitor, a resistor on a semiconductor substrate. It is an electronic device such as an inductor, or a display device such as a liquid crystal display device, an electroluminescence display device, or a plasma display device.
- a stable Q-switch pulse that does not depend on a change in the time interval between pulse repetitions can be obtained.
- the laser pulse caching apparatus and method of the present invention it is possible to irradiate a processed object with a uniform laser pulse at an arbitrary timing.
- the processing positions may be distributed on the substrate at unequal intervals. It is possible to irradiate a uniform laser pulse at the same arbitrary timing.
- stable processing with a Q switch laser pulse can be realized without the need for a continuous oscillation output of an external beam, such as AOM, and a branching element for selection of the Q switch pulse oscillation output section, which were conventionally required.
- an external beam such as AOM
- a branching element for selection of the Q switch pulse oscillation output section which were conventionally required.
- FIG. 1 An explanation of an apparatus for performing a processing method by laser beam irradiation of a conventional example relating to the present invention. Clear picture.
- FIG. 2 is an explanatory diagram of the operation of the conventional apparatus configuration of FIG.
- FIG. 3 is an apparatus configuration diagram of Examples 1 and 2.
- FIG. 4 is a diagram for explaining the operation of the apparatus according to the first embodiment.
- FIG. 5 is an ion energy level diagram of a laser medium for explaining the principle of the present invention.
- Nd Y
- FIG. 7 Device configuration diagram of Examples 3 and 4.
- the output mirror 7 ' is an output mirror having high reflectivity for the fundamental wave and high transmissivity for the second harmonic.
- a laser beam for excitation from a semiconductor laser oscillator 46 which is a laser excitation light source is converted into a parallel beam via a collimating lens 43 and guided to a polarization beam superimposing unit 44.
- the de-excitation laser oscillator 41 for reducing the laser upper level excitation density is a de-excitation source for irradiating the laser medium with a laser wavelength outside the laser oscillation target wavelength.
- the laser beam from the de-excitation laser oscillator 41 is collimated by the collimating lens 42,
- the two beams guided to the polarization beam superimposing unit 44 are superimposed or shifted in time, and the combined beam 45 travels on the same axis.
- the condensing optical system 3 causes laser resonance in the laser medium 5.
- the laser medium 5 is focused and irradiated through a high reflecting mirror 4 for the fundamental wavelength of the device.
- a nonlinear optical element 31 is disposed between the output mirror 7 'of the laser resonator and the Q switch element 6. With this configuration, the RF switch on / off timing of the Q switch element 6 between the laser resonator mirror 4 and the output mirror 7 ′ is controlled as shown in FIG.
- the light from the pumping semiconductor laser oscillator 46 is transmitted in space, but the light from the pumping oscillator can also be transmitted through a fiber. Is coupled to the fiber and transmitted coaxially.
- the oscillation wavelengths of the de-excitation laser oscillator 41 and the excitation semiconductor laser oscillator 46 are the excitation wavelengths when the laser medium is Nd + 3 ion-added Nd: YAG, Nd: YV04, Nd: YLF, etc.
- the known Nd energy level diagram power also uses a wavelength near 808 nm, and for de-excitation, laser light with a wavelength of 0.9 m, 1.1 / ⁇ ⁇ , and 1.3 m. Is valid. This is used in the laser medium Nd: Other transition wavelength originating from the 4 F on level of the lasers transition wavelengths commonly used in YAG crystal 946 nm, 1123 nm,
- the drive table 23 is driven by the drive unit 21 in response to a signal from the control unit 50.
- the control position of this drive table can be a closed loop position control system with an encoder (not shown)!
- the application of RF by controlling the application timing of RF1 in Fig. 4 (b) in order to drive the Q switch element 6 and the pumping semiconductor laser oscillator 46 for excitation, Start the excitation power (PL) in (c).
- the Q switch element 6 applies RF power from the Q switch drive unit 9 to the ultrasonic transducer of the Q switch element 6 to keep the laser resonator in a laser oscillation cutoff state with a large loss.
- an excitation laser output is applied to the laser medium 5 and is controlled by the control unit 50 so that the thermal temperature distribution in the laser medium is formed in a certain equilibrium state before laser oscillation.
- An oscillation command is sent to the pumping semiconductor laser oscillator 46 via the signal line 27.
- the time t3 for the processing position of the processing object 20 to reach the condensing point of the corresponding condensing lens 18 is Predictively, a command signal for starting a laser oscillation operation process is issued from the controller 50.
- a command signal for starting a laser oscillation operation process is issued from the controller 50.
- an oscillation command is sent from the control unit 50 to the deexcitation laser oscillator 41 as a control signal. Send via line 40.
- the oscillation command is issued by the trigger signal shown in Fig. 4 (a), and de-excitation laser oscillation is started at times tl, t5, and t9 as shown in (d) by the falling edge of the trigger signal. .
- the deexcitation laser light is collimated by the collimator lens 42 to be parallel, enters the polarization beam superimposing unit 44, passes through, and is irradiated to the laser medium 5 by the condenser lens 3.
- the laser medium 5 is preliminarily collimated by the collimating lens 43 from the pumping semiconductor laser oscillator 46 and excited by the pumping laser beam coaxially by the polarization beam superimposing unit 44, and the temperature of the crystal is increased.
- Excitation energy is accumulated at the position shown in Fig. 4 (e). Since the same crystal space is irradiated with the laser wavelength for de-excitation, it shifts to the lower level at a wavelength different from the fundamental wavelength of the upper level force laser oscillation, and light is emitted. This light has such a large loss that the laser resonator and the conditions for sufficient oscillation conditions are not satisfied!
- the density of the upper energy level accumulated so far can be reduced as shown in Fig. 4 (e) UL-1.
- De-excitation is performed for a predetermined time period tl t2, and then the laser medium is excited between t2 and t3 using only the excitation laser, and excitation is performed to generate an inversion distribution at the upper level (UL-2).
- the driving RF power to the Q switch element 6 is cut off between t3 and 14, and the transmission (open) state is established to oscillate the Q switch pulse 33G.
- the excitation density of the upper level decreases with laser oscillation (UL-3).
- the Q-switched noise output 33G releases 33G of pulse energy (f) QO corresponding to the energy accumulated in the laser medium 5 during the time t 2 ⁇ 3.
- RF power is applied to Q switch element 6 to turn off the Q switch again from time t4 after the oscillation of the Q switch pulse.
- the first machining target point is machined by the Q switch pulse that oscillates and emits during time t3-4 during this process.
- the timing of the Q switch pulse oscillation obtained from the position and scanning speed is also obtained for the second workpiece point, and de-excitation DPL1 is continued for a period of time t5-t6 based on that timing. Laser excitation is performed between time t6 and t7, and then RF is cut off between time t7 and t18 to oscillate Q switch pulse 33G.
- the Q switch If the time t3—7, t7—ti l, which is the interval between the pulses, changes, that is, the time between the times t4 t5, t8—9 is different, the DPL 1 of the deexcitation process (d) is switched to the Q switch. Since it was introduced between pulse oscillation cycles of repetitive operation, the upper level energy accumulated before tl, t5, and t9 is reduced by the deexcitation laser. (f) Q switch pulse output shown in QO The output energy of 33G is set by the excitation energy after de-excitation, so output equalization regardless of the pulse repetition frequency can be achieved. Therefore, by using these equalized pulse outputs, it became possible to precisely add the object to be measured regardless of the laser irradiation timing. The third and subsequent Q-switch pulse operations are a similar process.
- the laser output PL for excitation is operated at a constant intensity as shown in Fig. 4 (c).
- the excitation laser output PL may be modulated so as to achieve an output state to accelerate the deexcitation speed.
- the nonlinear optical element 31 is not necessary when the fundamental wavelength is used as the processing wavelength.
- the known nonlinear optical element is basically used. Install so as to satisfy the phase matching condition for the wave beam.
- the Q switch pulse is converted to the second harmonic and radiated from the output mirror 7 '.
- the mixed component 33IR is guided to the beam absorber 34, and only the second harmonic component 33G is collimated by the beam expander 15 and reflected by the reflecting mirror 16, and then the condenser lens 18 By forming a fine spot, the workpiece can be irradiated and processed.
- the input light needs to be polarized.
- an element with polarization in the resonator for example, when a laser medium and Nd: YVO or Nd: YLF are used, polarization oscillation is possible without any polarization means. You can enter.
- polarization means such as a polarizer in the optical path.
- the necessity of the polarization means shown here is common to all cases where a nonlinear optical element is inserted in the present invention.
- a continuous oscillation component may be mixed into the fundamental wave, and the wavelength-converted second harmonic component This is because only the component of the Q switch element that can obtain high conversion efficiency is output as the second harmonic component. Even if the continuous wave component is emitted on the same axis as the harmonics without being wavelength-converted, the wavelength filter 32 can remove other than harmonics. Therefore, the continuous component can be completely deleted.
- the burden of the oscillation suppression capability in the resonator with respect to the fundamental wave component of the Q switch element 6 can be greatly reduced.
- the Q switch element drive RF power is increased to increase the Q switch element drive power so that the continuous output component is not output. This is because, after outputting the suppressing force or continuous component, it must be deleted by AOM as explained in the prior art.
- the second embodiment is an example in which a continuous output component is alternately generated with a Q switch pulse in the fundamental wave oscillation.
- the configuration shown in Fig. 3 is used.
- FIG. 6 illustrates the operation according to this embodiment.
- the output of the semiconductor laser oscillator 46 for excitation is generated in advance, and the laser medium 5 is excited. During this period, the RF power of the Q switch element 6 is low enough to suppress the required energy accumulation level at the repetitive pulse rate.
- (B) RF1 is set to a relatively low level so as to reduce the RF power until it has diffractive power. Therefore, as the accumulation of excitation energy proceeds, the laser overcomes the suppression of the Q switch element 6 and starts continuous oscillation. Output a continuous low output LP as shown.
- de-excitation DPL1 is generated during (d) DPL tl— 2 and de-excited, and the stored energy is released as ASE, and the upper-level energy is (e) UL— N UL— 1 Consumed as indicated by (UL — 1).
- the excitation semiconductor laser cuts off the oscillation stopping power as in (c) PL tl-t2. Note that the de-excitation laser oscillation command is issued by the trigger signal shown in FIG.
- the excitation medium is again irradiated with excitation light to excite the laser medium 5, and necessary excitation level energy is accumulated (UL-2).
- RF application of Q switch element 6 is stopped, Q switch pulse oscillation is generated, and Q switch pulse 33G is emitted (UL-3).
- RF1 power is applied to the Q switch element 6 to excite the laser medium 5 from the pumping semiconductor laser oscillator 46, and the continuous oscillation component LP oscillates.
- de-excitation laser irradiation is performed at the required timing t5-6, excitation is performed for a predetermined time (t6-7) with the semiconductor laser for excitation, and then a Q switch pulse is oscillated repeatedly.
- the conversion efficiency of the nonlinear optical element 31 is proportional to the square of the power, so the conversion efficiency of the continuous output is compared to that of the Q switch pulse. Since it is overwhelmingly low, it passes through the nonlinear optical element 31 as the fundamental wave, is separated by the wavelength filter 32, and becomes heat by the beam absorber 34 and can be eliminated. Therefore, only the component converted from the Q switch pulse of the harmonic component is irradiated to the object to be processed.
- the de-excitation periods tl-t2, t5-t6, and t9-tlO can be zero. If zero, the de-excitation laser can be omitted, so from FIG. 3, the de-excitation laser transmitter 41, the control signal line 40, the collimating lens 42, the polarization beam superimposing unit 44, and the laser device
- the controller 50 may not have a function related to the de-excitation laser oscillator control.
- the continuous leakage component LP Overcoming the loss due to suppression capability, the continuous leakage component LP 'oscillates and continues until just before the Q switch pulse oscillation command timing t3, t7, ti l, and when the RF power is turned off, it is suppressed by applying RF power. Therefore, 33G of low peak Q switch pulse (h) Q '0 is obtained by the remaining gain. By converting this wavelength into a harmonic using a nonlinear optical element, the second harmonic Q switch output (i) QSHG 33G can be obtained. According to this method, the Q switch pulse 33G and the second harmonic output 33G 'can be obtained at a constant output up to a repetition rate that is high enough to prevent generation of the leak oscillation component LP. A stable harmonic Q-switch pulse that is independent of the pulse interval is obtained.
- Example 3 is an example in which a nonlinear optical element is used without squeezing a deexcitation laser oscillator.
- Figure 7 shows the configuration. The explanation is omitted because it is the same as Fig. 1, but in Fig. 7, a nonlinear optical element 31 is added, and it has a high reflectivity for the fundamental wave and a high transmission for the second harmonic. An output mirror 7 'having a rate characteristic is used.
- Figure 8 shows the operation when this is done.
- (A) shows the excitation laser power. Here, it is assumed that the signal is modulated by a continuous wave.
- (B) is a trigger signal. Trigger signal intervals tl-t2, t2-t3, and t3-t4 need not be constant.
- the oscillation suppression signal RF1 is applied to the Q switch element 6 as shown in (c).
- energy is stored in the laser medium. Since the RF1 application time is constant, the energy stored in the laser medium is constant even if the interval between trigger signals is not constant.
- the Q-switch pulse 33G is generated, and the force storage energy is constant. Therefore, a Q-switch pulse with constant energy can be obtained.
- This pulse is converted into a harmonic wave by the non-linear optical element 31 as it is or becomes a Q switch pulse 33G 'as shown in (e), and the force applied to the workpiece 20
- the energy of each pulse irradiated is constant.
- RF is applied to the Q switch element 6 for a certain period of time in response to the trigger signal, so that the energy storage time in the laser medium 5 is constant, so that a uniform Q switch pulse is obtained. There is an effect that can be obtained.
- the beam characteristics can be kept constant.
- a continuous wave may be generated between the Q switch pulses 33G.
- the continuous wave with low power originally has a very low conversion efficiency to the harmonics, so that only the fundamental wave component exits from the non-linear optical element 31. Since the fundamental wave is separated by the wavelength filter 32, the processed object 20 is not irradiated.
- the energy is made constant by generating a Q switch pulse in a state where the resonator has a loss.
- the configuration is the same as in Fig. 7.
- the operation at this time is shown in Fig. 9.
- the pump laser power is operated continuously.
- an RF signal for suppressing oscillation is applied to the Q switch element 6 in order to accumulate energy in the laser medium.
- the trigger intervals tl t2, t2-t3, t3-4, and t4-5 are arbitrary.
- the intensity of the oscillation suppression RF signal is multiplied by the fixed time modulation DRF1, DRF2, DRF3, etc.
- the modulation amount depends on the previous trigger interval (for example, 3-4 and t4 t5 for DRF4 and DRF5, respectively), and the longer the trigger interval, the smaller the decrease in RF signal strength.
- the Q value of the resonator increases as shown in (d).
- the energy stored in the laser medium 5 is released, and a Q switch pulse 30G is generated as shown in (e).
- the Q value does not rise sufficiently when the RF signal is weak but not zero.
- the energy of the generated Q switch pulse is determined by the energy stored in the laser medium and the Q value in the resonator, so if the former is large, the latter can be controlled by reducing the latter. Energy can be kept constant. That is, when the interval of the previous trigger force is long, the accumulated energy in the laser medium 5 is large, so the modulation factor of the RF signal is reduced, the Q value in the resonator is reduced, and the loss is increased.
- a Q switch pulse having a certain energy can be generated.
- a table indicating the modulation amount of the RF signal corresponding to the time interval of the trigger for generating the Q switch pulse with a constant energy is created and provided in the laser control device 50 in FIG. It is possible to implement this method. From the trigger pulse interval, the required modulation amount is read by referring to the table, and a predetermined RF modulation amount is given to the Q switch element 6 under the control of the laser controller 50.
- the energy of the Q switch pulse can be made constant, and the Q value is increased only when the laser is output, so that the excitation power can be utilized to the maximum and the energy utilization efficiency is high.
- FIG. 10 shows an example of the configuration of the second harmonic (SHG) resonator that is different from those shown in FIGS. 3 and 7.
- the de-excitation laser oscillator 41 is powerful as shown in FIG. 7.
- the de-excitation laser oscillator 41 shown in FIG. 3 for the configuration of the second harmonic resonator shown in FIG. It can be applied to a certain configuration.
- the use of the nonlinear optical element 31 is the same as in FIG. 3 or FIG. Furthermore, it has an end mirror 4 'that has total reflection characteristics for the fundamental wave and the second harmonic. This configuration has the advantage that the conversion efficiency is increased by reciprocating the fundamental wave through the nonlinear optical element 31.
- the wavelength converted from the fundamental wave by the nonlinear optical element is the third harmonic, the fourth harmonic or the fifth harmonic in addition to the second harmonic. Obviously, this can be achieved by using a conversion technique.
- the present invention uses only the Q switch pulse as the fundamental wave.
- each Q switch pulse output can be equalized regardless of the pulse repetition period. Therefore, there is an advantage that a configuration that does not require a continuous oscillation output elimination device can be realized. Also, by converting to harmonics, even if continuous components are mixed in the fundamental wave, only Q-switched noise can be used due to the difference in conversion efficiency and wavelength filter action. Either when using the fundamental wave output or when using the harmonic output Even in this case, since only a short pulse from the Q switch is irradiated in the relative high-speed scanning when scanning the workpiece, irradiation by a continuous component does not occur, and thermal effects also occur. Nah ...
- the circuit can be simplified by reducing the RF circuit output power of the Q-switch drive unit that operates in a high repetitive operating range.
- the configuration in which the laser medium is pumped coaxially through a high-reflection mirror has been shown, but the laser medium excitation may be modified by well-known side-surface excitation, such as laser diode staggered excitation or lamp excitation. Can be implemented.
- optical waveguide having a kind of laser active material with a plurality of holes in the periphery of the core in the direction of the force axis in the direction of the force axis and having a waveguide at the center is explained using a crystal containing Nd as the laser medium
- the stability of the laser oscillation mode can be further improved by reducing the influence of the refractive index fluctuation caused by the temperature change in the laser medium due to the temperature distribution formed in the laser medium.
- Examples of utilization of the present invention include cutting of circuit elements of silicon wafers of semiconductor memories, trimming of capacitors, resistors, inductances, etc., LCD display panel correction power, PDP display device correction processing, circuit board functions Applying to trimming and other laser precision processing of semiconductor substrates, it is possible to reduce the manufacturing cost of electronic components by improving the product yield by reducing the processing width and reducing the number of processed removals.
Abstract
Description
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KR (1) | KR20090018165A (ja) |
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Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
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JP2017120890A (ja) * | 2015-12-31 | 2017-07-06 | ルメンタム・オペレーションズ・リミテッド・ライアビリティ・カンパニーLumentum Operations LLC | 短パルスレーザの任意のトリガのための利得制御 |
WO2017142156A1 (ko) * | 2016-02-18 | 2017-08-24 | (주)이오테크닉스 | 레이저 가공 장치 및 방법 |
JP2018006394A (ja) * | 2016-06-28 | 2018-01-11 | ウシオ電機株式会社 | レーザ駆動光源装置 |
JP2018173407A (ja) * | 2017-03-30 | 2018-11-08 | 株式会社ミツトヨ | 位置検出器を用いた線形変位センサー |
JP6808114B1 (ja) * | 2020-03-10 | 2021-01-06 | 三菱電機株式会社 | 波長変換レーザ装置および波長変換レーザ加工機 |
EP4002611A4 (en) * | 2019-07-16 | 2023-01-11 | Nichia Corporation | Q SWITCHING RESONATOR AND PULSE GENERATOR |
Families Citing this family (3)
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---|---|---|---|---|
CN102371431B (zh) * | 2010-08-13 | 2015-06-10 | 豪晶科技股份有限公司 | 激光加工制程装置 |
CN102780155B (zh) * | 2012-07-02 | 2014-08-06 | 深圳市大族激光科技股份有限公司 | 一种激光q开关的输入信号控制装置及方法及激光设备 |
JP6970000B2 (ja) * | 2017-12-14 | 2021-11-24 | 株式会社キーエンス | レーザ加工装置及びレーザ加工方法 |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH02165883A (ja) * | 1988-12-19 | 1990-06-26 | Matsushita Electric Ind Co Ltd | レーザトリミング装置 |
JPH0833993A (ja) * | 1994-07-25 | 1996-02-06 | Seiko Epson Corp | レーザ加工装置及びレーザ加工方法並びに液晶パネル |
JPH08153925A (ja) * | 1994-11-30 | 1996-06-11 | Toshiba Corp | 連続励起qスイッチレーザ発振方法及びその装置 |
JPH08191168A (ja) * | 1995-01-12 | 1996-07-23 | Toshiba Corp | Qスイッチレ−ザ装置 |
JP2000101176A (ja) * | 1998-09-21 | 2000-04-07 | Miyachi Technos Corp | Qスイッチ型レーザ装置 |
JP2001352120A (ja) * | 2000-06-06 | 2001-12-21 | Matsushita Electric Ind Co Ltd | レーザ装置とその制御方法およびそれを用いたレーザ加工方法とレーザ加工機 |
JP2002252403A (ja) * | 2001-02-21 | 2002-09-06 | Keyence Corp | レーザ発振器およびそのレーザパルス制御方法 |
JP2006041191A (ja) * | 2004-07-27 | 2006-02-09 | Sumitomo Electric Ind Ltd | ホーリーファイバ |
-
2007
- 2007-05-18 CN CNA2007800202232A patent/CN101461105A/zh active Pending
- 2007-05-18 KR KR1020087031681A patent/KR20090018165A/ko not_active Application Discontinuation
- 2007-05-18 WO PCT/JP2007/060202 patent/WO2007138884A1/ja active Application Filing
- 2007-05-18 JP JP2008517838A patent/JPWO2007138884A1/ja active Pending
- 2007-05-22 TW TW096118223A patent/TW200810301A/zh unknown
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH02165883A (ja) * | 1988-12-19 | 1990-06-26 | Matsushita Electric Ind Co Ltd | レーザトリミング装置 |
JPH0833993A (ja) * | 1994-07-25 | 1996-02-06 | Seiko Epson Corp | レーザ加工装置及びレーザ加工方法並びに液晶パネル |
JPH08153925A (ja) * | 1994-11-30 | 1996-06-11 | Toshiba Corp | 連続励起qスイッチレーザ発振方法及びその装置 |
JPH08191168A (ja) * | 1995-01-12 | 1996-07-23 | Toshiba Corp | Qスイッチレ−ザ装置 |
JP2000101176A (ja) * | 1998-09-21 | 2000-04-07 | Miyachi Technos Corp | Qスイッチ型レーザ装置 |
JP2001352120A (ja) * | 2000-06-06 | 2001-12-21 | Matsushita Electric Ind Co Ltd | レーザ装置とその制御方法およびそれを用いたレーザ加工方法とレーザ加工機 |
JP2002252403A (ja) * | 2001-02-21 | 2002-09-06 | Keyence Corp | レーザ発振器およびそのレーザパルス制御方法 |
JP2006041191A (ja) * | 2004-07-27 | 2006-02-09 | Sumitomo Electric Ind Ltd | ホーリーファイバ |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2017120890A (ja) * | 2015-12-31 | 2017-07-06 | ルメンタム・オペレーションズ・リミテッド・ライアビリティ・カンパニーLumentum Operations LLC | 短パルスレーザの任意のトリガのための利得制御 |
JP2018056597A (ja) * | 2015-12-31 | 2018-04-05 | ルメンタム・オペレーションズ・リミテッド・ライアビリティ・カンパニーLumentum Operations LLC | 短パルスレーザの任意のトリガのための利得制御 |
US10135219B2 (en) | 2015-12-31 | 2018-11-20 | Lumentum Operations Llc | Gain control for arbitrary triggering of short pulse lasers |
WO2017142156A1 (ko) * | 2016-02-18 | 2017-08-24 | (주)이오테크닉스 | 레이저 가공 장치 및 방법 |
JP2018006394A (ja) * | 2016-06-28 | 2018-01-11 | ウシオ電機株式会社 | レーザ駆動光源装置 |
JP2018173407A (ja) * | 2017-03-30 | 2018-11-08 | 株式会社ミツトヨ | 位置検出器を用いた線形変位センサー |
JP7093208B2 (ja) | 2017-03-30 | 2022-06-29 | 株式会社ミツトヨ | 位置検出器を用いた線形変位センサー |
EP4002611A4 (en) * | 2019-07-16 | 2023-01-11 | Nichia Corporation | Q SWITCHING RESONATOR AND PULSE GENERATOR |
JP6808114B1 (ja) * | 2020-03-10 | 2021-01-06 | 三菱電機株式会社 | 波長変換レーザ装置および波長変換レーザ加工機 |
WO2021181511A1 (ja) * | 2020-03-10 | 2021-09-16 | 三菱電機株式会社 | 波長変換レーザ装置および波長変換レーザ加工機 |
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CN101461105A (zh) | 2009-06-17 |
JPWO2007138884A1 (ja) | 2009-10-01 |
TW200810301A (en) | 2008-02-16 |
KR20090018165A (ko) | 2009-02-19 |
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