TW201639654A - Angled LIFT jetting - Google Patents

Abstract

An apparatus for material deposition on an acceptor surface includes a transparent donor substrate having opposing first and second surfaces, such that at least a part of the second surface is not parallel to the acceptor surface, and including a donor film on the second surface. The apparatus additionally includes an optical assembly, which is configured to direct a beam of radiation to pass through the first surface of the donor substrate and impinge on the donor film at a location on the part of the second surface that is not parallel to the acceptor surface, so as to induce ejection of droplets of molten material from the donor film onto the acceptor surface.

Description

Angled laser induced forward transfer (LIFT) injection device

The present invention is generally directed to laser direct writing, and more particularly to methods and systems for laser induced forward transfer injection.

Laser-Induced Forward Transfer (LIFT) is a technology for direct printing of various materials such as metals and polymers. LIFT offers high print quality, yet advanced electronics contain three-dimensional (3D) patterns that are difficult to uniformly coat. Examples of prior art are provided below.

A material transfer system for the fabrication of small structures having a substrate, a material carrier having a deposited layer, and a laser facing the material carrier member is described in U.S. Patent No. 6,792,326, the disclosure of which is incorporated herein by reference. beam. The system operates in an additive mode of operation or a subtractive mode of operation such that the workpiece does not have to be removed from the tool when the mode of operation is changed.

A method for laser transfer and deposition of a rheological fluid is described in U.S. Patent No. 6,805,918, the disclosure of which is incorporated herein by reference. On the target substrate, a portion of the rheological fluid is caused to evaporate and the non-evaporating rheological fluid is pushed onto the receiving substrate.

A direct writing method and apparatus for fabricating a desired circuit component on a substrate surface of a microelectronic device in accordance with computer aided design (CAD) is described in U.S. Patent No. 7,277,770, the disclosure of which is incorporated herein by reference.

U.S. Patent Application Publication No. 2005/0095,367, the disclosure of which is incorporated herein by reference in its entirety, the entire entire entire entire entire entire entire entire entire entire entire entire entire disclosure The nozzle directs the viscous material to flow in a direction that is not perpendicular to the surface of the substrate. The non-perpendicular spray direction results in droplets that produce a reduced wetted area on the substrate.

The literature incorporated by reference in this patent application is hereby incorporated by reference in its entirety in its entirety in its entirety in the extent of the extent of the extent In addition to the definition of any term in a conflicting manner, only the definitions in this book should be considered.

One embodiment of the invention described herein provides an apparatus for depositing a material on a surface of a receptor comprising a transparent donor substrate having opposing first and second surfaces such that at least a portion of the second surface is Parallel to the receptor surface, and the transparent donor substrate includes a donor film on the second surface. The apparatus additionally includes an optical assembly configured to direct a beam of radiation through the first surface of the donor substrate and impinging at a location non-parallel to the second surface portion of the receptor surface On the donor film, droplets of molten material are induced to eject from the donor film onto the surface of the receptor.

In some embodiments, the second surface comprises a periodic structure. In other embodiments, the second surface comprises a multi-faceted structure. In still other embodiments, the second surface includes first and second facets oriented at opposing angles and coated with different respective donor films. In an alternative embodiment, the second surface includes first and second facets, wherein only the first facet is coated with the donor film. In an embodiment, the second surface comprises a curved structure.

There is further provided, in accordance with an embodiment of the present invention, an apparatus for material deposition, comprising a transparent donor substrate having opposing first and second surfaces such that at least a portion of the second surface is non-planar and the transparent The donor substrate includes a non-planar surface on the second surface Part of the donor film. The apparatus additionally includes an optical assembly configured to direct a beam of radiation through the first surface of the donor substrate and impinging on the donor film at a location on the non-planar portion of the second surface, A droplet of molten material is induced to eject from the donor film onto the surface of the receptor.

A method for material deposition is further provided in accordance with an embodiment of the present invention, comprising providing first and second facets having opposing first and second surfaces and having opposite angles oriented on the second surface a transparent donor substrate, and the transparent donor substrate includes a donor film on the first and second facets. The donor substrate is placed proximate to the acceptor substrate, wherein the second surface faces the acceptor substrate. a beam of radiation is directed through the first surface of the donor substrate and impinging on the donor film at a location selected in response to the first and second facets of the second surface to induce a small molten material A donor film dripping from the first and second facets is ejected onto the acceptor substrate.

A method for material deposition according to an embodiment of the present invention further includes providing a transparent donor substrate having opposing first and second surfaces and having a donor film on the second surface. The donor substrate is disposed proximate to a receptor surface of the acceptor substrate, wherein the second surface faces the acceptor substrate and is oriented at an oblique angle, ie, at a non-perpendicular angle, relative to the surface of the acceptor. A beam of radiation is directed through the first surface of the donor substrate and impinges on the donor film when the second surface is oriented at the oblique angle to induce droplets of molten material to be ejected from the donor film to The receptor is on the surface.

The invention will be more fully understood from the following detailed description of embodiments of the invention.

10‧‧‧Printing and writing device

11‧‧‧Users

12‧‧‧Electronic circuits

13‧‧‧Laser

14‧‧‧Installation surface

15‧‧‧Optical devices

16‧‧‧Optical Assembly/Static Assembly

17‧‧‧donor substrate

18‧‧‧ donor film

19‧‧‧ Donor

20‧‧‧Placement Accessories

21A‧‧‧second (lower) surface

21B‧‧‧lower surface

21C‧‧‧lower surface

21D‧‧‧lower surface

21E‧‧‧lower surface

22A‧‧‧Non-planar LIFT donor

22B‧‧‧Non-planar LIFT donor

22C‧‧‧Non-planar LIFT donor

22D‧‧‧Non-planar LIFT donor

22E‧‧‧Non-planar LIFT donor

23‧‧‧Operator terminal

23A‧‧‧Flat first (upper) surface

23B‧‧‧ upper surface

23C‧‧‧ upper surface

23D‧‧‧ upper surface

23E‧‧‧Flat upper surface

24‧‧‧Substrate

25‧‧‧Structural layer

25A‧‧‧ structure

25B‧‧‧ structure

25C‧‧‧ structure

25D‧‧‧ structure

25E‧‧‧ structure

26‧‧‧ Substantially similar to small noodles

26M‧‧‧Materials

27‧‧‧Control unit

28‧‧‧Laser beam

29‧‧‧ Angle

30‧‧‧Melted droplets of molten material

31‧‧‧ arrow

32‧‧‧ Substantially similar to small noodles

33A‧‧‧Receptor surface/top surface

34‧‧‧ Processor

35A‧‧‧Base surface

36‧‧‧ display

40‧‧‧ Substantially similar to small noodles

41‧‧‧ arrow

42‧‧‧ Substantially similar to small noodles

43‧‧‧ arrow

50‧‧‧ Substantially similar to small noodles

51‧‧‧ arrow

52‧‧‧ Substantially similar to small noodles

53‧‧‧ arrow

54‧‧‧ Substantially similar to small noodles

55‧‧‧ arrow

62‧‧‧ Substantially similar to small noodles

64‧‧‧ Substantially similar to small noodles

66‧‧‧Tilt angle

68‧‧‧ arrow

70‧‧‧ arrow

71‧‧‧Bend structure / bending element

72‧‧‧ arrow

73‧‧‧ radius of curvature

74‧‧‧ arrow

76‧‧‧ arrow

77‧‧‧flat lower surface

79‧‧‧ gap

D‧‧‧ gap width

H‧‧‧thickness

L‧‧‧Width

θ _e ‧‧‧spray angle

1 is a schematic perspective view of a system for direct writing on a substrate in accordance with an embodiment of the present invention; and FIG. 2 is a schematic side elevational view showing the details of the system of FIG. 1 in accordance with an embodiment of the present invention; 3 through 6 are schematic cross-sectional views showing details of a non-planar laser induced forward transfer (LIFT) donor in accordance with an embodiment of the present invention; and FIG. 7 is a diagram showing non-parallelism in accordance with an embodiment of the present invention. A schematic cross-sectional view of a detail of a non-planar LIFT donor of a bulk substrate.

Review

Embodiments of the invention described below provide methods and apparatus for enhancing the capabilities and usability of laser induced forward transfer (LIFT) technology. The enhancements provided by such embodiments are suitable for printing on electronic circuits containing various types of substrates, and are particularly suitable for printing on three-dimensional (3D) structures. The disclosed technology is in no way limited to such specific application content, however, the aspects of the embodiments described herein may also be applied (substantially modified in detail) to LIFT-based applications on substrates other than electronic circuit substrates. print. Enhancements include printing of both metallic and non-metallic materials.

In a typical LIFT-based system, a small distance between the donor surface and the acceptor substrate results in high print quality on the substrate. However, printing on the 3D structure on the substrate poses two challenges: the distance between the donor surface and the lower surface of the receptor may be large (low print quality at the receptor) and the vertical of the 3D structure of the substrate The coating on the sidewall may be poor ("step coverage").

Embodiments of the invention described below overcome some of these limitations by providing different, novel types of donor structures and orientations, as well as corresponding methods of operating the LIFT system. In some embodiments, the transparent donor substrate has opposing first and second surfaces such that at least a portion of the second surface is non-parallel to the receptor surface and includes a donor film thereon. The optical assembly is configured to direct a beam of radiation through the first surface of the donor substrate to impinge on the donor film at a location that is not parallel to the second surface portion of the receptor surface. Droplets of impact-induced molten material, such as metals and polymers, are ejected from the donor film onto the surface of the receptor.

In other embodiments, the second surface comprises multiple facet, periodic structures, At least some of the facets are coated with a donor film. The multiple facet structure includes a first substantially similar facet and a second substantially similar facet, and the first and second facets are oriented at opposite angles and coated with different respective donor films. In still other embodiments, the second surface of the donor comprises a first substantially similar facet and a second substantially similar facet that are not parallel to the horizontal surface of the substrate, and are parallel to the horizontal surface of the substrate but are not coated The third of the donor film is substantially similar to the facet. The third facet can be used to inspect the LIFT method in situ via the donor.

In an alternate embodiment, the second surface comprises a curved structure.

In another embodiment, the transparent donor substrate has opposing first and second surfaces such that at least a portion of the second surface is non-planar and the transparent donor substrate is on a non-planar portion of the second surface There is a donor film. The optical assembly directs a beam of radiation through the first surface of the donor substrate and impinges on the donor film at a location on the non-planar portion of the second surface to induce droplets of molten material to be ejected from the donor film to On the surface of the receptor.

System specification

1 is a schematic perspective illustration of a system for direct writing on a substrate 24 in accordance with an embodiment of the present invention. The system and its components shown herein are merely illustrative of the types of environments in which the techniques described herein can be implemented. These techniques can be implemented similarly using other types of suitable equipment and in other configurations.

The system of Figure 1 is constructed around a printing and writing device 10 that operates on a substrate 24 of an electronic circuit 12, such as a flat panel display (FPD) or printed circuit board (PCB), that is held on mounting surface 14. In the general LIFT method, substrate 24 is also referred to as a receiver or receptor. The terms "flat panel display", "FPD", "printed circuit board" and "PCB" are used herein generally to refer to a type of substrate material and method for deposition, a conductive material (such as a metal) or a non-conductive material (such as Dielectric and polymer) deposit any type of dielectric or metal or semiconductor substrate thereon. Device 10 can be used to deposit new layers, such as printing metal circuits on various substrates or any other electronic device.

Apparatus 10 includes an optical assembly 16 for use in laser induced forward transfer (LIFT) Laser and optics. Optical assembly 16 and its operational reference are described with respect to FIG. In some embodiments, such as by device 10, such as when patterning or layer deposition on a PCB or FPD or any other suitable device, the direct printing application can include being in situ (ie, monitoring during the printing process) And inspection), integration (ie monitoring and testing of selected devices as soon as the LIFT method is completed) or other diagnostic capabilities off-line by independent diagnostic systems.

The placement assembly 20 in the form of a bridge places the optical assembly 16 over the associated site on the substrate 24 by linear movement along the axis of the device 10. In other embodiments, the placement assembly 20 can take other forms, such as one (X) axis, two (X, Y) axes, or three (X, Y, Z) along the circuit 12 and below the static assembly 16. The axis of the mobile platform. As described below, control unit 27 controls the operation of the optics and placement assembly and performs other functions, such as temperature control, to perform the required inspection, printing, patterning, and/or other manufacturing and repair operations.

Typically, control unit 27 is in communication with operator terminal 23, which includes a general purpose computer including processor 34 and display 36, as well as a user interface and software.

2 is a schematic side elevational view of the detail of the display device 10, and particularly the optical assembly 16, in accordance with an embodiment of the present invention. The laser 13 emits pulsed radiation that is focused by the optics 15. The laser may comprise, for example, a pulsed Nd:YAG laser with a multiplied output, and the pulse amplitude of the laser may preferably be controlled by the control unit 27. (Control unit 27 can also be configured (although it is possible to utilize a non-trivial manner) to control the pulse duration.) Optics 15 can be similarly controlled to adjust the position and size of the focus formed by the laser beam.

In some embodiments, other lasers (not shown) or any other illumination source (such as an LED or a light) having different beam characteristics may be used. Other lasers can be operated at another wavelength and with another optics device, and can be used, for example, for surface inspection.

Optical assembly 16 is shown in Figure 2 in a LIFT configuration. The optics 15 focuses the beam from the laser 13 onto a donor body 19 comprising a donor substrate 17 in which one or more donor films 18 are deposited on the substrate 17. Typically, substrate 17 comprises a transparent optical material such as glass. Or a plastic sheet or other type of transparent substrate, such as a germanium wafer or a flexible plastic foil. The beam from the laser 13 (by placing the assembly 20) is aligned with the selected site on the substrate 24 of the circuit 12, and the donor 19 is placed above the site with the desired gap width D from the substrate. . Typically, this gap width is at least 0.1 mm, and the inventors have discovered that a gap width of 0.2 mm or even 0.5 mm or more can be used if the laser beam parameters are properly selected.

The optical device 15 focuses the laser beam onto the film 18 via the outer surface of the substrate 17, thereby causing droplets of molten material to be ejected from the film across the gap and onto the surface of the device substrate (eg, into the structured layer 25) ).

3 is a schematic cross-sectional view showing details of a non-planar LIFT donor 22A in accordance with an embodiment of the present invention. The donor 22A is transparent to the laser beam 28 and includes two surfaces, a first (upper) surface 23A that is generally perpendicular to the laser beam 28 and parallel to the plane of the substrate 24, and a second (lower) surface that faces the substrate 24. Surface 21A. In one embodiment, the lower surface of the donor 22A is non-planar and includes two or more facets that are not parallel to the substrate 24. In the example of FIG. 3, the lower surface of donor 22A includes substantially similar facets 32 and substantially similar facets 26. Facet 32 is generally parallel to laser 28, and facet 26 has a slope (gradient) and is coated with one or more films of material 26M to form a single or multiple layer stack of individual materials. In the present invention and in the scope of the patent application, facets having a flat and planar surface are employed.

During the LIFT method, laser beam 28 provides pulsed radiation onto donor 22A. Radiation passes through surface 23A and impinges on the donor film of selected facets 26. Since the selected facets are not parallel to the receptor surface 33A of the substrate 24 (here assuming parallel to the substrate surface 35A of the substrate), the molten material droplets 30 are ejected from the donor film at an angle 29 to the receptor surface 33A of the substrate 24. The receptor surface 33A of the substrate 24 is also referred to herein as the top surface 33A of the substrate. Typically, the spray of droplets 30 is perpendicular to facet 26 and is indicated by arrow 31. Thus, although the laser beam 28 is perpendicular to the substrate 24, the slope of the facet 26 results in the illustrated bevel jet, The droplets 30 are deposited on the sidewalls of the structure 25A on the substrate 24. As illustrated in the figure, structure 25A has a surface (such as a sidewall) that is not parallel to receptor surface 33A (i.e., not parallel to substrate surface 35A). In the following description, other structures 25B, 25C, 25D, 25E are mounted on the substrate 24. These other structures have the same properties as the structures 25A described herein, that is, the structures have surfaces that are not parallel to the surface of the substrate of the substrate 24.

In the example of Figure 3, the angle at which the droplets are ejected from the coated facets is primarily set by the design of the donor 22A.

In a typical LIFT process, a small distance between the donor 22A and the substrate 24 (and structure 25A) results in high print quality on the substrate 24 and structure 25A. In addition, the multiple facet structure provides for easy ejection in a predefined desired direction perpendicular to each facet and thus achieves high coating uniformity of the sidewalls of the 3D structure.

In some embodiments, the lower surface of donor 22A contains a periodic structure (as shown in Figure 3). In other embodiments, the structure of the lower surface of the donor 22A can have a non-periodic structure with facets of different slopes along the lower surface of the donor 22A. That is, the structure may be different from the center of the donor 22A to the edge of the donor. For example, the angle of inclination of the facets at the edges of the donor 22A may be steeper than the angle of the facets at the center.

In an alternate embodiment, the lower surface of donor 22A may comprise more than two facets as will be described in accordance with FIG.

4 is a schematic cross-sectional view showing details of a non-planar LIFT donor 22B in accordance with an embodiment of the present invention. The donor 22B is transparent to the laser beam 28 (not shown in Figure 4). The upper surface 23B of the donor 22B is parallel to the top surface 33A of the substrate 24. The lower surface 21B of the donor 22B is non-planar and includes multiple facet structures that are not parallel to the receptor surface 33A of the substrate 24, such as substantially similar to the facets 40 and substantially similar facets 42. Each facet thus has a different slope relative to the receptor surface of the substrate 24. In one embodiment, the facets are oriented opposite the beam 28, not necessarily at equal angles (e.g., +45° and -30°). Both facets can be coated with different individual donor films, such as material 26M as described in accordance with Figure 3 and another a material.

The dual material structures can be fabricated using a variety of techniques, such as lithography, direct evaporation (in the case of metal coatings), or bi-angled by placing different facets with different materials (eg, Tapered) structure. (In some embodiments, some facets may remain uncoated.) During LIFT operation, the two materials may be ejected substantially simultaneously, such as by using two or more parallel beams. Alternatively or additionally, high repetition rate lasers may be scanned to effectively achieve simultaneous injection. Simultaneous ejection can be used to form a mixed material (e.g., a compound) on the substrate 24. Further alternatively or additionally, the two materials can be continuously printed to form a hybrid material structure.

Since the facets 40 and 42 are not parallel to the surface of the substrate 24, the molten material droplets 30 are ejected from the donor film at an angle (i.e., the angle 29 in FIG. 3) to the surface of the substrate 24. In one embodiment, facets 40 and 42 are each coated with a film formed of a similar or different material. In an alternate embodiment, only one facet (e.g., facet 40) is coated with a film. Droplet 30 is ejected from face 40 and indicated by arrow 41, and droplet 30 is typically ejected at an angle perpendicular to surface 40 to coat the left side wall of structure 25B. Arrow 43 illustrates the droplet 30 being ejected from the facet 42, typically at a spray angle perpendicular to the facet 42 to coat the right side wall of the structure 25B. Both ejections also coat the top surface of the substrate 24 and structure 25B parallel to the upper surface of the donor 22B.

In some embodiments, the ejection of droplets 30 occurs simultaneously, and in the case of different materials on each facet, the ejection of droplets 30 can form a mixed film (e.g., compound or alloy) of the respective materials on substrate 24. In other embodiments, the droplets 30 are ejected from the facets 40 before or after the droplets 30 are ejected from the facets 42. In the case of different materials on the facets 40 and 42, the droplets 30 are sequentially ejected to form a multilayer structure or a mixed material structure in the same layer on the substrate 24.

The ejection angle of the droplets is defined by the slope of the facets 40 and 42, respectively. In some embodiments, the coating materials on facets 40 and 42 are similar to print the same material throughout structure 25B and substrate 24. In other embodiments, the coating material can be different to structure Mixed or multilayer materials are printed on 25B and substrate 24.

FIG. 5 is a schematic cross-sectional view showing details of a non-planar LIFT donor 22C in accordance with an embodiment of the present invention. The donor 22C is transparent to the laser beam 28 (not shown in Figure 5). In some embodiments, as described below, donor 22C can be configured to be transparent to another laser or another illumination source (such as an LED or light) that can be used for LIFT method verification.

The upper surface 23C of the donor 22C is parallel to the top surface 33A of the substrate 24. The lower surface 21C of the donor 22C includes substantially similar facets 50 and substantially similar facets 52 that are not parallel to the surfaces 33A and 35A of the substrate 24, and substantially similar facets 54 that are parallel to the surface 33A.

As described with reference to Figure 4, facets 50 and 52 may be coated with the same material or different materials on each facet. In some embodiments, facet 54 is uncoated and can be used for in situ inspection during the LIFT method to monitor the quality of the LIFT printing process. Alternatively or additionally, the uncoated facets can be used in other inspection applications, such as alignment and/or alignment. The same laser or other laser (not shown in Figure 5) or any other suitable illumination source (e.g., LED or lamp) as described above may be used for inspection via uncoated facets.

In other embodiments, the facets 54 may be coated with a material to be ejected, generally perpendicular to the substrate 24 in the ejection indicated by arrow 55. The ejection from the facets 50 and 52 (described by arrows 51 and 53, respectively) is generally perpendicular to the facets 50 and 52, respectively. Arrow 51 illustrates the left side wall and top surface of droplet 30 coating structure 25C from facet 50. Arrow 55 illustrates the top surface of droplet 30 coating structure 25C. Arrow 53 illustrates the right side surface of droplet 30 coating structure 25C. The ejection angles of the facets 50 and 52 are mainly set by the respective slopes of the facets.

Figure 6 is a schematic cross-sectional view showing details of a non-planar LIFT donor 22D in accordance with an embodiment of the present invention. The donor 22D is transparent to the laser beam 28. The upper surface 23D of the donor 22C is parallel to the top surface 33A of the substrate 24. The lower surface 21D of the donor 22D includes one or more curved structures 71 coated by a donor film on top of the flat lower surface 77 of the donor 22D. Each curved structure 71 has a thickness h and a width L. Structure 71 is also referred to herein as a component 71. By way of example, four bending elements 71 are shown in Figure 6, and it is assumed that portions of the respective balls have equal radii of curvature 73.

However, it should be appreciated that element 71 can comprise substantially any curved surface, and thus can, for example, comprise portions of a cylinder or portions of another curved entity, such as an ellipsoid. Additionally, element 71 may be disposed on surface 21D in a periodic manner, or may be configured to be non-periodic.

Typically, the width L of each element 71 is substantially greater than the thickness h of the same element to avoid distortion of the beam spot when the beam 28 strikes the element 71. In one embodiment, the thickness h is about 100 μm or less, and the gap 79 between the donor 22D and the surface 33A is in the range of 200 μm to 300 μm or more. These values of thickness and gap ensure that the printing conditions between donor 22D and substrate 24 are substantially uniform.

The curvature of element 71 and the location of beam 28 on the element define the ejection angle θ _{e of} droplet 30 from the element, which is typically ejected vertically into the impact region. Thus, the operator can control the position of the beam 28 on the curved donor to achieve the desired ejection angle for a given droplet 30 to achieve the desired position on the substrate. In general, by controlling the position of beam 28, donor 22D, and/or substrate 24, the operator can select the ejection angle of droplets 30 at any angle within a continuous range, and thus can change each droplet 30 at surface 33A. And the landing angle and landing position on the structure 25D. In one embodiment, the continuous range of ejection angles measured in accordance with beam 28 is between +30° and -30°.

For example, when beam 28 strikes the center of element 71 (here assuming parallel to surface 33A), as illustrated by arrow 72, droplet 30 is typically ejected vertically to surface 33A. In this case, the droplets coat the top surface of surface 33A or 25D. When the beam 28 strikes the right side of the element 71, the droplet 30 is ejected from the donor film at an angle as indicated by arrow 74. In this case, the droplets are dropped onto the left side wall of the receptor surface 33A or structure 25D at a non-perpendicular angle (such as the angle 29 described in Figure 3). Similarly, when the beam 28 impinges on the left side of the element 71, the droplet 30 is ejected from the donor film at an angle opposite to the angle at which the beam impinges on the right side of the element, as illustrated by arrow 76. In this case, the droplets are The opposite angle (as compared to the example represented by arrow 74) falls onto the right side wall of receptor surface 33A or structure 25D.

In the tight packing element 71, the width L is specified by the maximum allowable discharge angle and the thickness h of the element 71. If θ _m is the maximum ejection angle, the width of the element 71 (for the component sphere portion) is given by the following equation:

Thus, for example, the thickness h is set to 100 μm and the maximum ejection angle is assumed to be 30°, and the curved surface width L is about 750 μm, which is substantially larger than the typical spot size. Similar considerations apply to other dense curved structures.

7 is a schematic cross-sectional view showing details of a non-planar LIFT donor 22E that is not parallel to the surfaces 33A and 35A of the substrate 24 in accordance with an embodiment of the present invention. The donor 22E is inclined at an oblique angle 66 that is planed on the donor 22E. The upper surface 23E is measured between a horizontal line parallel to the surfaces 33A and 35A of the substrate 24. Surface 23E acts as a defined planar surface for donor 22E, and slope angle 66 is between surface 23E and a line parallel to surface 33A, surface 35A of substrate 24.

The donor 22E is transparent to the laser beam 28 and includes a lower surface 21E that is coated by the donor film and faces the substrate 24 at an oblique angle. Structure 25E is located on substrate 24 and typically has a three dimensional (3D) structure as shown in FIG.

In one embodiment, the user 11 (FIG. 1) of the device 10 identifies the topographical features on the 3D structure of the structure 25E and places the donor 22E such that the lower surface of the donor is tilted (ie, non-perpendicular) The angle of the surface faces the surface of the 3D structure. Once the donor 22E and substrate 24 have been placed, the user directs the beam 28 onto the donor 22E such that material is ejected from the donor film generally perpendicular to the lower surface of the donor 22E onto the 3D structure. For example, if the angle 66 is equal to 10° and the droplet 30 is ejected perpendicular to the lower surface of the donor 22E, the droplets will be ejected at 100° relative to the horizontal line parallel to the substrate 24 and will be relative to The angle 80° (90° - 10°) measured by the surface 33A of the substrate 24 landed on the top surface of the structure 25E.

In some embodiments, surface 21E of donor 22E includes a plurality of facets, such as facets 62 and 64, that are typically coated with a donor film. In other embodiments, surface 21E is planar (ie, does not include facets) and is coated with a donor film.

During the LIFT method, the laser beam 28 emits pulsed radiation onto the donor 22E. Radiation passes through surface 23E and impinges on the donor film on the surface of the lower portion of donor 22E to induce droplets of molten material to be ejected from the donor film onto the surface of the receptor, which includes the surface of substrate 24 in the example of FIG. Part 33A and the upper surface portion of structure 25E.

In the first case of the planar (non-minimized) surface 21E of the donor 22E, the ejection angle from the donor film is continuous across the donor, and thus the beam 28 is ejected toward the structure 25E at an angle of 90° + an angle 66. drop. Thus, the droplets 66 land on the top surface of the substrate 24 and structure 25E at a non-perpendicular angle. As described in the above example, the angle 66 is equal to 10°, and thus the ejection angle from the donor 22E is 100°, and the drop angle on the top surface of the structure 25E is 80°. In the case where the droplets land on the side walls of the structure 25E that is perpendicular to the surface of the substrate 24, the angle of fall will typically be 10 relative to the surface of the sidewalls.

In the second case (shown in Figure 7), the lower surface of donor 22E includes substantially similar facets 62 and substantially similar facets 64. In this embodiment, during the LIFT method, beam 28 passes through surface 23E and impinges on the donor film of facet 62, causing droplet 30 to be ejected toward the right side wall and horizontal top surface of structure 25E (indicated by arrow 68). . In this case, the discharge and landing angles are determined by the angle of view 66 and the angle of inclination of the facet 62 relative to the surface 21E.

For example, if the angle 66 is equal to 10° and the angle of the facet 62 relative to the lower surface of the donor 22E is 60° and the surface perpendicular to the facet 62 is ejected, the angle ejected from the facet 62 (arrow 68) is equal to 10°+60°+90°, which is equal to 160° with respect to the lower surface of the donor 22E. The drop angle of the droplet 30 on the top surface of the structure 25E will be 20° (90°-70°) and the drop angle on the left vertical side wall of the structure 25E will be 70°.

Similarly, beam 28 passes through the upper surface of donor 22E and impacts on facet 64 On the body membrane, droplets 30 are caused to eject toward the right side wall and horizontal surface of structure 25E (indicated by arrow 70).

In both embodiments, the non-zero tilt angle 66 provides a particular location on the donor 22E that is closer to the substrate 24 than the parallel donor acceptor configuration. Smaller distances between the donor and the acceptor typically result in high print quality in the LIFT process.

In Figure 7, the left side of the donor 22E along with the facets 62 and 64 provides a shorter distance between the film on the donor 22E and the structure 25E due to the lower angle of inclination 66 than the prior art system. These shorter distances provide droplets 30 of higher print quality on structure 25E. As shown in Figure 7, the tilted embodiment provides high printing performance across a non-uniform height of structure 25E with the right side of structure 25E being higher than the left side of the structure.

As illustrated in Figure 7, the combination of the non-zero tilt angle 66 with the multiple facet structures on the lower surface of the donor 22E provides flexibility to adjust the LIFT method in accordance with the particular topography of the structure 25E. For example, the highest 3D structure in Figure 7 is in the right side of structure 25E, and thus donor 22E is tilted to the left. In the opposite case where the 3D structure is higher on the left side of the structure 25E, the right side of the donor 22E can be tilted downward, which means that the tilt angle 66 is opposite to the angle shown in FIG. For example, angle 66 is not 10° but is -10° (or 170°). The combination of an adjustable tilt angle and a multi-faceted structure of the donor provides flexibility that can be used to achieve a smaller distance between the surface 21E of the donor 22E and the structure 25E, and thus provides any type of 3D for the structure 25E. High print quality of features.

It should be understood that the above-described embodiments are cited by way of example, and the invention is not limited to the particulars shown and described. Rather, the scope of the present invention includes the combinations and sub-combinations of the various features described above, as well as variations and modifications thereof which are apparent to those skilled in the art in light of the above description.

21A‧‧‧second (lower) surface

22A‧‧‧Non-planar LIFT donor

23A‧‧‧Flat first (upper) surface

24‧‧‧Substrate

25A‧‧‧ structure

26‧‧‧ Substantially similar to small noodles

26M‧‧‧Materials

28‧‧‧Laser beam

29‧‧‧ Angle

30‧‧‧Melted droplets of molten material

31‧‧‧ arrow

32‧‧‧ Substantially similar to small noodles

33A‧‧‧Receptor surface/top surface

35A‧‧‧Base surface

Claims (22)

An apparatus for depositing a material on a surface of a receptor, comprising: a transparent donor substrate having opposing first and second surfaces such that at least a portion of the second surface is non-parallel to the surface of the receptor, and the transparent a donor substrate comprising a donor film on the second surface; and an optical assembly configured to direct a beam of radiation through the first surface of the donor substrate and impinging on a surface that is not parallel to the receptor The donor film is positioned on the second surface portion to induce droplets of molten material to be ejected from the donor film onto the surface of the receptor. The device of claim 1, wherein the second surface comprises a periodic structure. The device of claim 1, wherein the second surface comprises a plurality of faceted structures. The device of claim 3, wherein the second surface comprises first and second facets oriented at opposite angles and coated with different respective donor films. The device of claim 3, wherein the second surface comprises first and second facets, and wherein only the first facet is coated with the donor film. An apparatus for material deposition, comprising: a transparent donor substrate having opposing first and second surfaces such that at least a portion of the second surface is non-planar, and the transparent donor substrate is included in the second a donor film on a non-planar portion of the surface; and an optical assembly configured to direct a beam of radiation through the first surface of the donor substrate and impinge on a non-planar portion of the second surface The donor film is placed on the donor film to induce droplets of molten material to be ejected from the donor film onto the surface of the receptor. The device of claim 6, wherein the second surface comprises a periodic structure. The device of claim 6, wherein the second surface comprises a curved structure. The device of claim 6, wherein the second surface comprises a plurality of faceted structures. The device of claim 9, wherein the second surface comprises first and second facets oriented at opposite angles and coated with different respective donor films. The device of claim 9, wherein the second surface comprises first and second facets, and wherein only the first facet is coated with the donor film. A method for material deposition, comprising: providing a transparent donor substrate having opposing first and second surfaces and having first and second facets oriented at opposite angles on the second surface, and a donor film disposed on the first and second facets; placing the donor substrate adjacent to the acceptor substrate, wherein the second surface faces the acceptor substrate; and directing a beam of radiation through the donor a first surface of the substrate and impinging on the donor film at a location selected in response to the first and second facets of the second surface to induce droplets of molten material from the first and second facets The donor film is ejected onto the acceptor substrate. The method of claim 12, wherein the ejecting of the molten material droplets from the donor film to the first and second facets is performed simultaneously. The method of claim 12, wherein the droplets of molten material are ejected from the donor film onto the first and second facets in sequence. A method for depositing a material, comprising: providing a transparent donor substrate having opposing first and second surfaces and having a donor film on the second surface; placing the acceptor surface adjacent the acceptor substrate a donor substrate, wherein the second surface faces the acceptor substrate and is oriented at an oblique angle relative to the surface of the acceptor; and directs a beam of radiation through the first surface of the donor substrate, and at the second surface The oblique angle is directed against the donor film to induce droplets of molten material to be ejected from the donor film onto the surface of the receptor. The method of claim 15, wherein placing the donor substrate comprises identifying a three-dimensional (3D) shape of a topographical feature on the surface of the receptor, and orienting the donor substrate in response to the 3D shape. The method of claim 15, wherein the second surface comprises a curved structure. The method of claim 15 wherein the second surface of the donor substrate comprises a plurality of faceted structures. The method of claim 18, wherein the multiple facet structure comprises first and second facets oriented at an opposite angle and coated with the donor film. The method of claim 19, comprising simultaneously ejecting the droplets from the donor films of the first and second facets onto the 3D shape. The method of claim 19, comprising sequentially ejecting the droplets from the first and second facets of the donor film onto the 3D shape. The method of claim 15, wherein the second surface of the donor substrate comprises a periodic structure.