JP4650205B2 - Laser scribing method for multilayer substrate, laser scribing method for droplet discharge head, multilayer substrate, droplet discharge head - Google Patents

Description

  The present invention relates to a laser scribing method for a multilayer substrate, a laser scribing method for a droplet discharge head, and a multilayer substrate processed by the laser scribing method and a droplet discharge head.

  In a conventional droplet discharge head as a multilayer substrate, for example, as described in Patent Document 1 below, a compliance substrate is bonded to one surface of a sealing substrate, and an actuator substrate is bonded to the other surface. ing. Adhesive is used for adhesion, and in order to secure the adhesive force with the sealing substrate, the adhesive is applied from the edge of the substrate by applying pressure so that the adhesive fills almost the entire surface of the compliance substrate and the actuator substrate. Adhesion is performed to such an extent that leaks out. On the other hand, when the droplet discharge head configured as described above is cut by laser light, for example, as described in Patent Document 2 below, the condensing point of the laser light is aligned with the inside of the sealing substrate. In other words, the modified region is formed in the condensing point portion by irradiating the laser light so that the power density of the laser light is maximized at the condensing point and utilizing the phenomenon of multiphoton absorption. Thereby, it cut | disconnects starting from a modification | reformation area | region.

JP 2005-138518 A JP 2002-192371 A

  However, if the area where the adhesive leaks out due to the adhesion of the substrate as described above corresponds to the area where the laser beam is irradiated, the laser beam hits the leaked adhesive and scatters when the area is irradiated with the laser beam. There was a problem that the light condensing property was lowered.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a laser scribing method for a multilayer substrate, a droplet discharge head, and the like capable of suppressing a decrease in the condensing property of irradiated laser light. An object is to provide a laser scribing method, a laminated substrate, and a droplet discharge head.

  In order to solve the above-described problems, in the present invention, the first laser beam irradiation area provided on one surface of the first substrate and the first adhesion area to which the second substrate should be bonded are within the first adhesion area. , A recess is provided in at least one of the bonding surface of the first substrate and the bonding surface of the second substrate at a position in the vicinity of the first laser light irradiation region, and the first substrate and the second substrate are bonded with an adhesive. The present invention includes a manufacturing process for forming a laminated substrate bonded by the above and an irradiation process for irradiating a laser beam toward the first laser beam irradiation region.

  According to the laser scribing method for a laminated substrate according to the present invention, in the manufacturing process, a recess is provided on at least one of the adhesion surface of the first substrate and the adhesion surface of the second substrate. The recess is provided in the vicinity of the first laser light irradiation region in the first adhesion region. When the first substrate and the second substrate are bonded to each other with an adhesive, the adhesive spreads on the bonding surfaces of the two substrates and accumulates in the recesses, thereby suppressing the spread of leakage to the first laser light irradiation region. Therefore, when the laser beam is irradiated toward the first laser beam irradiation region in the irradiation step, the adhesive that causes the laser beam to scatter does not leak and spread in the first laser beam irradiation region. The decline in sex can be suppressed.

  In the manufacturing process of the laser scribing method of the multilayer substrate according to the present invention, the second laser light irradiation region which is a region corresponding to the first laser light irradiation region provided on the other surface facing one surface of the first substrate; Of the second adhesion region corresponding to the position of the second substrate, the adhesion between the adhesion surface of the first substrate and the third substrate is located in the vicinity of the second laser light irradiation region in the second adhesion region. At least one of the surfaces is provided with a recess, and a laminated substrate in which the first substrate and the third substrate are bonded with an adhesive is formed. In the irradiation step, a laser is directed toward the first or second laser light irradiation region. You may irradiate light.

  According to this, in the manufacturing process, the third substrate is further provided on the other surface opposite to the one surface of the first substrate to which the second substrate is bonded, and is bonded to the first substrate with the adhesive. . A recess is provided in at least one of the adhesive surface of the first substrate and the adhesive surface of the third substrate, and suppresses the spread of the adhesive from leaking to the second laser light irradiation region. Therefore, when the first or second laser light irradiation region is irradiated with the laser beam in the irradiation step, the adhesive does not leak on either side, so that it is possible to suppress a decrease in light condensing performance.

  The concave portion of the laser scribing method of the multilayer substrate of the present invention may be formed along the first and second laser light irradiation regions in a plan view of the first substrate.

  According to this, since the concave portion is formed along the laser beam irradiation line, the prevention of adhesive leakage can be further improved.

  The gist of the multilayer substrate of the present invention is that it is processed by the laser scribing method for the multilayer substrate.

  According to the multilayer substrate of the present invention, a concave portion is provided in the member so that the adhesive does not leak and spread in the laser light irradiation area, and the laser scribe can be surely performed by the concave portion, thereby providing a highly reliable multilayer substrate. can do.

  The present invention provides a laser scribing method for a droplet discharge head processed by the laser scribing method for a multilayer substrate, wherein the first substrate of the multilayer substrate is a sealing substrate, and the second substrate is a compliance substrate. Yes, the third substrate is an actuator substrate.

  According to the laser scribing method for a droplet discharge head of the present invention, in the manufacturing process, a recess is provided on at least one of the adhesion surface of the sealing substrate and the adhesion surface of the compliance substrate. The recess is provided in the vicinity of the first laser light irradiation region in the first adhesion region. When the sealing substrate and the compliance substrate are bonded by an adhesive, the adhesive spreads on the bonding surfaces of the two substrates and accumulates in the recesses, thereby suppressing the spread of leakage to the first laser light irradiation region. In addition, an actuator substrate is further provided on the other surface opposite to one surface of the sealing substrate to which the compliance substrate is bonded, and is bonded to the sealing substrate with an adhesive. A recess is provided in at least one of the adhesive surface of the sealing substrate and the adhesive surface of the actuator substrate, and suppresses the leakage spread of the adhesive to the second laser light irradiation region. Therefore, when the first or second laser light irradiation region is irradiated with the laser beam in the irradiation step, the adhesive does not leak on either side, so that it is possible to suppress a decrease in light condensing performance.

  The gist of the droplet discharge head of the present invention is that it is processed by the above-described laser scribing method of the droplet discharge head.

  According to the droplet discharge head according to the present invention, since the concave portion is provided in the member so that the adhesive does not leak and spread in the laser light irradiation area and laser scribing can be performed reliably, a highly reliable droplet discharge head. Can be provided.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings.

(Configuration of laminated substrate)
First, the configuration of the multilayer substrate will be described. FIG. 1 shows an outline of a mother substrate, FIG. 1 (a) shows a plan view, and FIG. 1 (b) shows a cross-sectional view taken along line AA of FIG. 1 (a).

  In FIG. 1A, a mother substrate W is configured by partitioning and forming droplet discharge heads 10 as a plurality of laminated substrates. And as shown in FIG.1 (b), the compliance board | substrate 14 as a 2nd board | substrate is adhere | attached on one surface of the sealing substrate 11 as a 1st board | substrate, An actuator substrate 15 as a third substrate is bonded. One droplet discharge head 10 irradiates laser light to the first and second laser light irradiation regions 40 a and 40 b provided on the sealing substrate 11 to form a modified region inside the sealing substrate 11. And is cut out from the mother substrate W.

  2 shows the configuration of the droplet discharge head 10, FIG. 2 (a) shows a cross-sectional view, and FIG. 2 (b) shows a plan view.

  In FIG. 2, the droplet discharge head 10 is bonded to the sealing substrate 11 made of silicon single crystal, the compliance substrate 14 having the supply holes 21 for supplying the functional liquid, the actuator substrate 15, and the actuator substrate 15. The nozzle plate 30 has the nozzle hole 31 formed. The actuator substrate 15 includes a drive film 22, a wiring 25 for applying a voltage to the drive unit 22a that is a part of the drive film 22, and a silicon oxide layer 26a and a zirconium oxide layer 26b that are in contact with the drive unit 22a. The pressure chamber member 27 includes an elastic film 26 and a pressure chamber 27a.

  The sealing substrate 11 is provided with a first laser light irradiation region 40a and a first adhesion region 12 on one surface, and a recess 17 is provided in the first adhesion region 12 at a position near the first laser light irradiation region 40a. Is formed. In addition, the second laser light irradiation region 40b and the second adhesion region 13 are provided on the other surface opposite to the one surface of the sealing substrate 11, and the second laser light irradiation region 40b in the second adhesion region 13 is provided. A recess 19 is formed in the vicinity. As shown in FIG. 2B, the recesses 17 and 19 are formed along the first and second laser light irradiation regions 40a and 40b. In the present embodiment, the first recesses 19 and 19 are provided in a lattice shape. Along with the shapes of the second laser light irradiation regions 40a and 40b, the second laser light irradiation regions 40a and 40b are formed in a square shape.

  The sealing substrate 11 and the compliance substrate 14 are bonded to each other with an adhesive 16 in the first bonding region 12. The adhesive 16 spreads over almost the entire bonding surface of the compliance substrate 14 and accumulates in the recess 17 formed in the vicinity of the first laser light irradiation region 40a.

  The sealing substrate 11 and the actuator substrate 15 are bonded to each other with an adhesive 18 in the second bonding region 13. The adhesive 18 spreads over almost the entire adhesive surface of the actuator substrate 15 and accumulates in the recess 19 formed in the vicinity of the second laser light irradiation region 40b.

(Laser substrate laser scribing method)
Next, a laser scribing method for the multilayer substrate will be described. First, a laser irradiation apparatus used for irradiating a laser beam and cutting the laminated substrate will be described.

  FIG. 3 is a schematic diagram showing the configuration of the laser irradiation apparatus. As shown in FIG. 3, a laser irradiation apparatus 100 includes a laser light source 101 that emits pulsed laser light, a dichroic mirror 102 that reflects the emitted pulsed laser light, and a condensing unit that collects the reflected pulsed laser light. As a condensing lens 103. Further, a stage 107 on which a mother substrate W constituting the droplet discharge head 10 to be processed is placed, and an X axis as a moving means for moving the stage 107 in the X and Y axis directions with respect to the condenser lens 103. A slide part 110 and a Y-axis slide part 108 are provided. Further, the Z-axis slide mechanism 104 as an adjusting means for adjusting the position of the focused point of the pulsed laser light by changing the position of the focusing lens 103 in the Z-axis direction with respect to the mother substrate W placed on the stage 107. It has. Furthermore, an imaging device 112 is provided that is located on the opposite side of the condenser lens 103 with the dichroic mirror 102 interposed therebetween.

  The laser irradiation apparatus 100 includes a main computer 120 that controls each of the above components. The main computer 120 includes an image processing unit 124 that processes image information captured by the imaging apparatus 112 in addition to a CPU and various memories. is doing. The imaging device 112 incorporates a coaxial incident light source and a CCD (solid-state imaging device). Visible light emitted from the coaxial incident light source passes through the condenser lens 103 and is focused.

  Connected to the main computer 120 are an input unit 125 for inputting data of various processing conditions used in laser processing and a display unit 126 for displaying various information at the time of laser processing. In addition, a laser control unit 121 that controls the output, pulse width, and pulse period of the laser light source 101, and a lens control unit 122 that drives the Z-axis slide mechanism 104 to control the position of the condenser lens 103 in the Z-axis direction. It is connected. Further, a stage control unit 123 that drives a servo motor (not shown) that moves the X-axis slide unit 110 and the Y-axis slide unit 108 along the rails 109 and 111, respectively, is connected.

  The Z-axis slide mechanism 104 that moves the condensing lens 103 in the Z-axis direction has a built-in position sensor capable of detecting the moving distance, and the lens control unit 122 detects the output of the position sensor and collects the light. The position of the lens 103 in the Z-axis direction can be controlled. Therefore, the thickness of the substrate W can be measured by moving the condenser lens 103 in the Z-axis direction so that the focus of the visible light emitted from the coaxial incident light source of the imaging device 112 is aligned with the surface of the substrate W. It is.

  The laser light source 101 is an Nd: YAG laser that generates pulsed laser light. Other lasers that can be used for the laser light source 101 include an Nd: YVO4 laser, an Nd: YLF laser, and a titanium sapphire laser.

  In this embodiment, the stage 107 is supported by the Y-axis slide unit 108, but is supported by the X-axis slide unit 110 by reversing the positional relationship between the X-axis slide unit 110 and the Y-axis slide unit 108. It is good also as a form. Moreover, it is preferable to support the stage 107 on the Y-axis slide part 108 via the θ table. According to this, it is possible to make the mother substrate W more perpendicular to the optical axis 101a.

  Next, a laser scribing method for the multilayer substrate will be described. 4 to 6 are process diagrams showing a laser scribing method of a droplet discharge head as a laminated substrate, and FIGS. 4A to 4C and FIGS. 6 (g) and 6 (h) show an irradiation process for irradiating the droplet discharge head with laser light, and FIG. 6 (i) shows a break for individually cutting the droplet discharge head. A process is shown.

  In FIG. 4A, recesses 17 and 19 and a sealing portion 23 are formed on both surfaces of the sealing substrate 11. These formations can be performed by wet etching or dry etching, but wet etching in which the recesses 17 and 19 and the sealing portion 23 can be formed at the same time is preferable. The concave portion 17 is a first adhesion region of the sealing substrate 11 and is formed at a position in the vicinity of the first laser light irradiation region 40a. The recess 19 is a second adhesion region of the sealing substrate 11 and is formed at a position in the vicinity of the second laser light irradiation region 40b.

  In FIG. 4B, a liquid adhesive 16 a is applied in the first adhesive region 12. For example, an epoxy resin is used as the liquid adhesive 16a.

  In FIG. 4C, the compliance substrate 14 is bonded to the sealing substrate 11 via the liquid adhesive 16a. At this time, the compliance substrate 14 is pressed to the sealing substrate 11 side so that the liquid adhesive 16a spreads widely on the bonding surface of the compliance substrate 14. The liquid adhesive 16 a pushed out in the direction of the edge of the compliance substrate 14 by the pressure flows into the recess 17. Thereafter, drying is performed to form a solidified adhesive 16. Drying is performed by room temperature drying or heat drying.

  In FIG. 5 (d), a liquid adhesive 18 a is applied in the second adhesive region 13. An epoxy resin is used for the liquid adhesive 18a.

  In FIG. 5E, the actuator substrate 15 is bonded to the sealing substrate 11 via the liquid adhesive 18a. At this time, the actuator substrate 15 is pressed toward the sealing substrate 11 so that the liquid adhesive 18a spreads widely on the bonding surface of the actuator substrate 15. The liquid adhesive 18 a pushed out in the direction of the edge of the actuator substrate 15 by the pushing thickness flows into the recess 19. Thereafter, drying is performed to form a solidified adhesive 18. Drying is performed by room temperature drying or heat drying.

  In FIG. 5F, if necessary, the surface of the actuator substrate 15 opposite to the sealing substrate 11 is back-ground and processed to have a specified thickness. Thereafter, the common ink chamber 20 and the pressure chamber 27a are formed by etching. Then, the nozzle plate 30 is joined to the actuator substrate 15.

  In FIG. 6G, from the condensing lens 103 that condenses the laser light emitted from the laser light source 101 using the laser irradiation device 100, toward the first laser light irradiation region 40a of the sealing substrate 11, Laser light 103 a is irradiated in a direction perpendicular to the surface of the sealing substrate 11. The laser light source 101 is an Nd: YAG laser that generates pulsed laser light. In this case, the wavelength is 1064 nm, the pulse width is 30 ns, and the repetition frequency is 100 kHz. The condenser lens 103 is an objective lens having a magnification of 100 times and a numerical aperture (NA) of 0.8.

  During laser light irradiation, the mother substrate W is placed on the stage 107 of the laser irradiation apparatus 100 so that the condensing point P of the laser light 103a is positioned in an arbitrary first laser light irradiation region 40a of the mother substrate W. Then, the servo motor is driven to move the X-axis slide unit 110 and the Y-axis slide unit 108. Thereafter, the thickness data of the sealing substrate 11 is acquired using the imaging device 112, and the position of the condensing point P of the laser light 103a is adjusted based on the acquired data. The condensing point P at the start of laser light irradiation is set to a position that exceeds 50% in the thickness direction of the sealing substrate 11 from the first laser light irradiation region 40a.

  The laser beam 103 a is irradiated while the mother substrate W is moved relative to the condenser lens 103. In this case, the speed at which the mother substrate W is moved in response to the irradiation with the laser beam 103a is approximately 300 mm / s. Further, the condensing point P is set in a direction approaching the first laser beam irradiation region 40a, and the laser beam 103a is irradiated. Then, scanning is repeated until the condensing point setting position substantially reaches the surface of the sealing substrate 11, and a modified region is formed inside the sealing substrate 11.

  In FIG. 6H, the laser beam 103 a is irradiated in a direction perpendicular to the surface of the sealing substrate 11 toward the second laser light irradiation region 40 b of the sealing substrate 11. The condensing point of the laser beam 103a is set to the depth position of the condensing point P at the start of laser light irradiation in FIG. 6G, and the condensing point P approaches the second laser light irradiation region 40b as described above. The laser beam 103a is irradiated while setting the position in the direction. Then, scanning is repeated until the condensing point setting position almost reaches the surface of the sealing substrate 11 to form a modified region inside the sealing substrate 11.

  6 (i), by applying external stress to the mother substrate W, the sealing substrate 11 is individually separated from the formed modified region as a starting point, and the droplet discharge head 10 is formed.

  Therefore, according to the present embodiment, there are the following effects.

  (1) A concave portion 17 is formed in the first adhesion region 12 of the sealing substrate 11, and when the compliance substrate 14 is adhered by an adhesive, the leaked liquid adhesive 16a flows into the concave portion 17, and the first laser In order to suppress the leakage spread of the adhesive 16 to the light irradiation region 40a, when the laser beam 103a is irradiated toward the first laser light irradiation region 40a, it is possible to suppress a decrease in light condensing property.

  (2) A recess 19 is formed in the second adhesion region 13 of the sealing substrate 11, and when the actuator substrate 15 is adhered by an adhesive, the leaked liquid adhesive 18a flows into the recess 19 and the second laser In order to suppress the spread of the leakage of the adhesive 18 to the light irradiation region 40b, when the laser beam 103a is irradiated toward the second laser light irradiation region 40b, it is possible to suppress a decrease in light condensing property.

  (3) Since the recesses 17 and 19 are formed in the first and second adhesion regions 12 and 13 and have a substantially rectangular shape along the first and second laser light irradiation regions 40a and 40b. The leakage spread of the adhesives 16 and 18 can be substantially prevented with respect to the first and second laser light irradiation regions 40a and 40b.

  The present invention is not limited to the above-described embodiment, and the following modifications can be given.

  (Modification 1) In this embodiment, the recess is provided on the sealing substrate 11 side, but the present invention is not limited to this. You may provide in the adhesion surface of the compliance board | substrate 14 corresponding to the same position. Even in this case, since the liquid adhesive 16a flows into the concave portion provided in the compliance substrate 14, it is possible to prevent the adhesive 16 from spreading to the first laser light irradiation region 40a. Also in the actuator substrate 15, a concave portion may be provided on the bonding surface corresponding to the same position. Even in this case, since the liquid adhesive 18a flows into the recess provided in the actuator substrate 15, it is possible to prevent the adhesive 18 from spreading to the second laser light irradiation region 40b.

  (Modification 2) In the present embodiment, the recesses 17 and 19 are provided on both surfaces of the sealing substrate 11, but the present invention is not limited to this. For example, in consideration of the thickness of the sealing substrate 11, when the sealing substrate 11 can be cut by irradiating laser light only from the first laser light irradiation region 40a, it corresponds to the first laser light irradiation region 40a. You may form the recessed part 17 only in a surface. Even if it does in this way, the sealing substrate 11 can be cut | disconnected, without reducing the condensing property of a laser beam.

The outline of a mother board is shown, (a) is a top view and (b) is a sectional view. The structure of the droplet discharge head as a multilayer structure member is shown, (a) is sectional drawing, (b) is a top view. Schematic which shows the structure of a laser beam irradiation apparatus. The manufacturing method of the droplet discharge head as a multilayer structure member is shown, (a)-(c) is process drawing which shows a manufacturing process. The manufacturing method of the droplet discharge head as a multilayer structure member is shown, (d)-(f) is process drawing which shows a manufacturing process. The manufacturing method of the droplet discharge head as a multilayer structure member is shown, (g), (h) is a laser beam irradiation process, (i) is a process figure which shows a breaking process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Droplet discharge head, 11 ... Sealing board | substrate, 12 ... 1st adhesion area | region, 13 ... 2nd adhesion area | region, 14 ... Compliance board | substrate, 15 ... Actuator board | substrate, 16, 18 ... Adhesive agent, 17, 19 ... Recessed part 40a ... first laser light irradiation region, 40b ... second laser light irradiation region, 100 ... laser irradiation device, 103a ... laser light, W ... mother substrate.

Claims (6)

A first laser light irradiation region provided on one surface of the first substrate;
A first adhesion region provided on the one surface of the first substrate and to be adhered to the second substrate;
A laser scribing method for a laminated substrate including:
Providing a recess in the first adhesive region;
A substrate bonding step of bonding the first substrate and the second substrate with an adhesive;
When the first laser beam irradiation region is projected in the thickness direction of the first substrate, the laser beam is focused on a part of a three-dimensional region formed inside the first substrate, and is then moved to the internal position. A modified region forming step for forming a modified region;
A step of applying stress to the first substrate after the modified region forming step and dividing the laminated substrate starting from the modified region;
In the modified region forming step, a plurality of modified regions are formed in the thickness direction of the first substrate.
A laser scribing method for a multilayer substrate, comprising: In the laser scribing method of the multilayer substrate according to claim 1,
The laminated substrate is
A second laser light irradiation region provided on a surface facing the one surface of the first substrate;
A second bonding region provided on a surface of the first substrate facing the one surface and to be bonded to a third substrate;
Further including
Providing a recess in the second adhesive region;
A substrate bonding step of bonding the first substrate and the third substrate with an adhesive;
A laser scribing method for a multilayer substrate , further comprising: In the laser scribing method of the multilayer substrate according to claim 1 or 2,
The method of laser scribing a laminated substrate, wherein the recess is formed along the first and second laser light irradiation regions in a plan view of the first substrate. A laminated substrate processed by the laser scribing method for a laminated substrate according to any one of claims 1 to 3. A laser scribing method for a droplet discharge head processed by the laser scribing method for a multilayer substrate according to any one of claims 1 to 3,
The laser scribing method for a droplet discharge head, wherein the first substrate of the multilayer substrate is a sealing substrate, the second substrate is a compliance substrate, and the third substrate is an actuator substrate. . A droplet discharge head processed by the laser scribing method for a droplet discharge head according to claim 5.

Images