FABRICATING NON-LIGHT-EMITTING VARIABLE TRANSMISSION LAMINATES

A method of repairing an electroactive laminate is disclosed. The method can include locating a defect in the electroactive laminate and laser ablating around the defect using laser pulses in a pattern, where a first laser pulse is followed by a second laser pulse in succession, and wherein the pattern comprises a space between any two laser pulses being fired in succession, and wherein the pattern comprises overlapping pulses between a pulse fired in a first circumferential pass and a pulse fired in a second circumferential pass.

FIELD OF THE DISCLOSURE

The present disclosure is directed to forming a non-light-emitting variable transmission laminate device and specifically for defect repair in those laminate devices.

BACKGROUND

A non-light-emitting variable transmission device can reduce glare and the amount of sunlight entering a room. During the fabrication process of the non-light-emitting variable transmission device, defects can be formed which reduce yield, form an electrical short, affect the appearance of the device (e.g., non-uniform tinting), or reduce the operational lifetime of the device. As such, there is a need for improvement in fabricating non-light-emitting, variable transmission devices and laminates.

DETAILED DESCRIPTION

The terms “normal operation” and “normal operating state” refer to conditions under which an electrical component or device is designed to operate. The conditions may be obtained from a data sheet or other information regarding voltages, currents, capacitances, resistances, or other electrical parameters. Thus, normal operation does not include operating an electrical component or device well beyond its design limits.

The use of “a” or “an” is employed to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. This description should be read to include one or at least one and the singular also includes the plural, or vice versa, unless it is clear that it is meant otherwise.

The use of the word “about”, “approximately”, or “substantially” is intended to mean that a value of a parameter is close to a stated value or position. However, minor differences may prevent the values or positions from being exactly as stated. Thus, differences of up to ten percent (10%) for the value are reasonable differences from the ideal goal of exactly as described.

Manufacturing an electrochromic laminate has unique challenges with respect to defects. In one embodiment, a laminate can be electrochromic material and laminate material between two substrates. In another embodiment, a laminate can be an assembly where two or more substrates are joined with a polymer based interlayer material. Defects that occur during the manufacturing of electroactive laminates can cause optical defects in the final device appearance. In non-laminated electroactive devices, a repair process ablates material surrounding a defect to repair such defect. The encapsulation of electrochromic devices within laminate assemblies introduces additional challenges related to laser ablation repair process. Electroactive laminates can include non-light-emitting, variable transmission devices, electrochromic devices, and liquid crystal devices. Since the defects are trapped in the laminate assembly, pressure can build up in the stack as part of the repair process, and lead to film delamination and bubble formation which in turn leads to poor performance of the electroactive device. The methods for fabricating an electroactive laminate with improved defect repair are disclosed. By successfully repairing the electroactive laminate device, the device can have an increased yield, without an electrical short or other defect that would affect the appearance and performance of the device, and an increased operational lifetime.

Embodiments as illustrated in the figures and described below help in understanding particular applications for implementing the concepts as described herein. The embodiments are exemplary and not intended to limit the scope of the appended claims.

Although not desired, during manufacturing, an electroactive device may be formed that contains a defect.FIG.1includes a cross-sectional view of a portion of an electroactive device with a stack of layers, according to one embodiment. In one embodiment, the electroactive device124can be a non-light-emitting, variable transmission device. In one embodiment, the electroactive device124can include an electrochromic material and an interlayer that are between two substrates. In another embodiment, the electroactive device124can include a first transparent conductive layer112, a cathodic electrode layer114, an anodic electrode layer118, a second transparent conductive layer122, and a laminate layer120. In one embodiment, the device124can also include an ion conducting layer116between the cathodic electrode layer114and the anodic electrode layer118. In another embodiment, the electroactive device124can include a first substrate, a second substrate, a first transparent conductive layer between the first and second substrate, a second transparent conductive layer between the first and second substrate, a first electrochromic material between the first and second transparent conductive layers, a second electrochromic material between the first and second transparent conductive layers, and a laminate layer between the first and second electrochromic materials. The first transparent conductive layer112can be between a first substrate100and a second substrate102. The cathodic electrode layer114can be between the first transparent conductive layer112and the anodic electrode layer118. The anodic electrode layer118can be between the cathodic electrode layer114and the second transparent conductive layer122. The laminate layer120can be on the second transparent conductive layer122. In one embodiment, the laminate layer120can include an electrically insulating material. In one embodiment, the laminate layer120can include a material selected from the group consisting of a polyurethane, polyvinyl butyral (PVB), ionomers such as ionoplast like SentryGlas Plus (SGP), ethylene vinyl acetate (EVA), silicone based optically clear resin, and acrylic based optically clear resin. In another embodiment, the laminate layer120can include a liquid or gel-like polymer. In another embodiment, the laminate layer120may contain the electrochromic material. In another embodiment, the laminate layer120may contain a laminating adhesive film.

The first substrate100and the second substrate102can each include a glass substrate, a sapphire substrate, an aluminum oxynitride substrate, a spinel substrate, or a transparent polymer. In a particular embodiment, the first substrate100and the second substrate102can be float glass or a borosilicate glass and have a thickness in a range of 0.025 mm to 4 mm thick. In another particular embodiment, the first substrate100and/or the second substrate102can include ultra-thin glass that is a mineral glass having a thickness in a range of 10 microns to 300 microns.

The first transparent conductive layer112and second transparent conductive layer122can include a conductive metal oxide or a conductive polymer. Examples can include a indium oxide, tin oxide or a zinc oxide, either of which can be doped with a trivalent element, such as Sn, Sb, Al, Ga, In, or the like, or a sulfonated polymer, such as poly (3,4-ethylenedioxythiophene), or the like, or sulfonated polyaniline and polypyrrole, or one or several metal layer(s) or a metal mesh or a nanowire mesh or graphene or carbon nanotubes or a combination thereof. The transparent conductive layers112and122can have the same or different compositions.

The cathodic layer114and the anodic layer118can be electrode layers. In one embodiment, the cathodic layer114can be an electrochromic layer. In another embodiment, the anodic layer118can be a counter electrode layer. The cathodic electrode layer114can include an inorganic metal oxide material, such as WO3, V2O5, MoO3, Nb2O5, TiO2, CuO, Ir2O3, Cr2O3, Co2O3, Mn2O3, or any combination thereof and have a thickness in a range of 20 nm to 2000 nm. The anodic electrode layer118can include any of the materials listed with respect to the cathodic electrode layer114and may further include nickel oxide (NiO, Ni2O3, or combination of the two) or iridium oxide, and Li, Na, H, or another ion and have a thickness in a range of 20 nm to 1000 nm.

The ion conductive layer116(sometimes called an electrolyte layer) can be optional and can have a thickness in a range of 1 nm to 1000 nm in case of an inorganic ion conductor or 5 microns to 1000 microns in case of an organic ion conductor. The ion conductive layer116can include a silicate with or without lithium, aluminum, zirconium, phosphorus, boron; a borate with or without lithium; a tantalum oxide with or without lithium; a lanthanide-based material with or without lithium; another lithium-based ceramic material particularly LixMOyNz where M is one or a combination of transition metals or the like.

Although not desired, a defect, such as a particle or other contaminate, can be introduced into the electroactive device124. As seen inFIG.1, while depicted in the cathodic electrode layer114, the defect could be in other layers of the electroactive device124. In one embodiment, the defect125may be located between any of the other layers or between the substrate100and the second conductive layer122. In one embodiment, the defect125can be in the anodic electrode layer118. In another embodiment, the defect125can be in the ion conductive layer116. The defect125can be a particle or other contaminate that can cause a short within the electroactive device124. The defect125may be from a patterning sequence, laser scribes, from a substrate handling tool, from a coating on a deposition chamber or material that breaks away during transferring the substrate into or out of the deposition tool or during a pump down or back fill cycle, or the like. The defect125may be formed during manufacturing of the electroactive device124and other layers can be deposited over the defect125without being detected until the deposition of the entire device is complete.

As will be described in more detail with respect toFIGS.2and3, repairing the defect within the electroactive device124according to procedures described herein can reduce the likelihood of failure of the electroactive device and prevent electrical shorts within the device. As seen inFIG.2, a flow diagram200for eliminating a defect in an electroactive device, in accordance with one embodiment is seen. The process below is discussed in conjunction with an electroactive device, as seen inFIG.3.

In operation, as a result of manufacturing, the electroactive device124can have a defect125within one of the layers. Not all devices that are manufactured contain a defect. Accordingly, the formation of the electroactive device and repair can begin at operation210by locating a defect within the electroactive device124. In one embodiment, the defect can be within any of the layers between the substrate100and laminate layer120. The defect may be detected by running current through the electroactive device124after the device has gone through the manufacturing process. During operation, an electroactive transmission device can operate with voltages on bus bars (not seen) being in a range of 0 V to 3 V. Other voltage may be used with the electroactive device or if the composition or thicknesses of layers within an electrochromic stack are changed. The voltages on bus bars may both be positive (1 V to 4 V), both negative (−5 V to −2 V), or a combination of negative and positive voltages (−1 V to 2 V), as the voltage difference between bus bars are more important than the actual voltages. Furthermore, the voltage difference between the bus bars may be less than or greater than 3 V. After reading this specification, skilled artisans will be able to determine voltage differences for different operating modes to meet the needs or desires for a particular application. The embodiments are exemplary and not intended to limit the scope of the appended claims. In an embodiment, locating the defect can occur through visual inspection. For example, the defect may be visible to the human eye or with the use of one or more tools or systems. In another embodiment, locating the defect can be performed with equipment.

At operation220, the defect125may be eliminated from the electroactive device124. The device124can be a laminate. In one embodiment, eliminating the defect can be to eliminate the short caused by the defect125. In one embodiment, eliminating the defect125can be to ablate one or more of the layers of the electroactive laminate device124that surround the defect125. In one embodiment, the laser can ablate at least one of the first transparent conductive layer112or the second transparent conductive layer122. In one embodiment, removing the defect can be performed with a full spectrum laser. The laser can ablate one or more layers of the electroactive laminate device124that surround the defect125. In a more particular embodiment, the laser is operated with pulse duration between 200 fs and 10 ns, such as between 250 fs and 1250 fs, or such as between 300 fs and 1000 fs. In yet a more particular embodiment, the laser is operated with a wavelength between 450 nm and 600 nm, between 500 nm and 550nm, or between 510 nm and 525 nm. In yet a further embodiment, the laser is operated with a wavelength of approximately 515 nm. In an embodiment, the laser is operated at a same pulse duration during the entire removal step. In another embodiment, the laser is operated at a same wavelength during the entire removal step. In a different embodiment, the laser can be operated with a variable pulse duration, a variable wavelength, or a combination thereof. In one embodiment, the laser can be fired from the side of the device that contains the substrate100. In other words, the laser can be fired through the substrate100. In another embodiment, the laser can be fired from a side of the device that contains the substrate102. Utilizing a laser beam that continuously circumscribes around the defect to eliminate the defect in a laminated device causes delamination and bubbling thereby causing a worse defect in the electroactive device. In short, instead of eliminating the defect, using a continuous beam causes more detrimental effects. The present disclosure focuses on utilizing more than one laser pulse in a pattern.

FIGS.3A-3Cshow a top view of an electroactive laminate during various steps in the process of eliminating the defect within an electroactive device. The electroactive device300can be similar to the electroactive device described above with respect toFIG.1. In one embodiment, before laser ablating the defect, the substrate100can be heated to between 40° C. and 90° C. In another embodiment, the laser ablation can occur at a temperature between 10° C. and 40° C.

In one embodiment, a first laser pulse302is followed by a second laser pulse304, where there is a space between the first laser pulse302and the second laser pulse304. The laser pulses form a laser spot of ablated material on the device. In one embodiment, the pulse overlap between the first laser pulse302and the second laser pulse304is about zero. In one embodiment, the pulse overlap between the first laser pulse302and the second laser pulse304is a negative overlap. In one embodiment, the pulse overlap between two sequentially fired laser pulses can be about zero. In one embodiment, the pulse overlap between two sequentially fired laser pulses can be negative. The laser pulses follow in succession in a circumferential manner in one pass around the defect125. In one embodiment, the distance between successive laser pulses in one particular pass can be between 0.5 nm and 500 nm. The method continues by firing one or more laser pulses circumferentially around the defect in two or more passes. In other words, the pulses can travel 360 degrees around the defect125in one turn or pass and the pulses can take more than one turn or pass around the defect125. A turn or pass can include a starting point and ending point being in about the same location. In other words, a path of the laser can form a closed loop. In another embodiment, the laser can be maintained in a steady state and the electroactive device300can be rotated relative to the laser.

As seen inFIG.3B, a third laser pulse306can be fired in a second turn around the defect. The third laser pulse306can be the first laser pulse of a second pass. In other words, even though the second laser pulse304is fired before the third laser pulse306, the third laser pulse306is closer to the first laser pulse302than the second laser pulse304. In one embodiment, a second pass of the laser can form a closed loop around the defect125. In one embodiment, the third laser pulse306is closer to the second laser pulse304than the first laser pulse302and is fired during a second turn or pass around the defect125. In one embodiment, a pulse overlap between the first laser pulse302and the third laser pulse306can be greater than zero. In one embodiment, the third laser pulse306can overlap the first laser pulse302between 1% and 99%. In one embodiment, the third laser pulse306can overlap the first laser pulse302by between 10% and 90%. In one embodiment, the one or more laser pulses that are fired in a second turn around the defect125can overlap with one or more of the laser pulses that are fired in the first turn around the defect125. As can be seen inFIG.3B, a fourth laser pulse308can overlap a second laser pulse304. The fourth laser pulse308can be a second pulse of the second pass. In one embodiment, the pulses are fired in at least two rounds. As seen inFIG.3C, once all the spaces between the individual pulses have been eliminated, a circumferential scribe322can be made around the defect125in order to electrically isolate the defect125from the rest of the electroactive device300. While shown inFIGS.3A-3Cas circular, the laser pattern that surrounds and isolates the defect125can be any geometric shape, such as a square, rectangular, triangular, polygonal, etc.

FIG.4is an illustration of a cross-sectional view of the electroactive device424after the defect repair has been completed. As can be seen inFIG.4, after undergoing the method described above, the defect125is electrically isolated from the rest of the electroactive device424. In one embodiment, the defect125remains in the electroactive device424. In one embodiment, the laser can ablate one or more layers of the electroactive device424in a pattern as described above. The pattern can include individual spots430or beams that overlap in a circumferential manner around the defect125, as seen inFIG.3C. In one embodiment, the one or more individual laser spots430are not uniform. In one embodiment, the one or more laser spots430have varying depths. In one embodiment, the one or more laser spots430can have different sizes. In one or more embodiments, the one or more laser spots430can have different shapes. In one embodiment, the one or more laser spots430can have different sizes and different shapes.

FIGS.5A and5Billustrate an optical microscope image of two different methods of laser ablation used to repair a defect (not shown) in an electroactive laminate device.FIG.5Ashows a continuous pulsed laser ablation process completed in at least one pass using pulse overlap greater than zero.FIG.5Bshows a pulsed laser ablation process utilizing the method described above, where a pulse overlap is less than zero between any two sequential laser pulses fired in a single pass. A trench530is formed around a repaired area that contains a defect. The trench530can be non-uniform. In one embodiment, the trench530can have varying depths. In another embodiment, the trench530can have varying widths. In another embodiment, the trench530can have a double ring configuration formed from individual laser spots. As can be seen inFIG.5A, significant damage515to the laminate layer and delamination513occurs. Delamination513is seen inFIG.5Aas a lighter or more clear color within and surrounding the circle created by the laser as compared to the color511within the functioning area of the device.

Embodiments as described above can provide benefits over other systems with electroactive devices. Repairing a defect using pulses that are fired in a pattern that circumferentially surrounds the defect, as described above, can eliminate delamination and bubbling problems otherwise seen in a continuous ablation process.

Embodiment 1. A method of repairing an electroactive assembly is disclosed. The method can include locating a defect in the electroactive assembly; and laser ablating around the defect using laser pulses in a pattern, where the pattern can include a first laser pulse followed by a second laser pulse in succession, and where the pattern can include a space between any two laser pulses being fired in succession.

Embodiment 2. The method of embodiment 1, where the electroactive assembly further can include electrochromic material, an interlayer, a first substrate, and a second substrate, where the electrochromic material and the interlayer are both between the first substrate and the second substrate.

Embodiment 3. The method of embodiment 2, where in the interlayer can include a material selected from the group consisting of a polyurethane, polyvinyl butyral (PVB), ionoplast like SentryGlas Plus (SGP), and ethylene vinyl acetate (EVA).

Embodiment 4. The method of embodiment 1, where the electroactive assembly further can include a first substrate, a cathodic layer, an anodic layer, an interlayer, a first transparent conductive layer, and a second transparent conductive layer.

Embodiment 5. The method of embodiment 1, where the laser is operated with a wavelength between 450 nm and 600 nm, such as between 500 nm and 550 nm, or between 510 nm and 525 nm.

Embodiment 6. The method of embodiment 1, where the first laser pulse does not overlap the second laser pulse.

Embodiment 7. The method of embodiment 1, where laser ablating around a defect is accomplished in at least two circumferential passes.

Embodiment 8. The method of embodiment 7, where the pattern can include overlapping pulses between a pulse fired in a first pass and a pulse fired in a second pass.

Embodiment 9. The method of embodiment 8, where a first pass can include moving the laser 360 degrees around the defect from a first starting point.

Embodiment 10. The method of embodiment 9, where a second pass can include moving the laser 360 degrees around the defect from a second starting point, where the first starting point is different from the second starting point.

Embodiment 11. The method of embodiment 1, where before laser ablating the defect, the substrate is heated to between 40° C. and 90° C.

Embodiment 12. The method of embodiment 1, where laser ablating the defect occurs at a temperature between 10° C. and 40° C.

Embodiment 13. The method of embodiment 1, where a pulse overlap of the first pulse and the second pulse is about zero.

Embodiment 14. The method of embodiment 1, where a pulse overlap of the first pulse and the second pulse is negative.

Embodiment 15. The method of embodiment 1, where the laser is operated with a pulse duration between 200 fs and 10 ns, such as between 250 fs and 1250 fs, or between 300 fs and 1000 fs.

Embodiment 16. The method of embodiment 4, where the laser pulses ablate at least one of the first transparent conductive layers or the second transparent conductive layer of the electroactive assembly.

Embodiment 17. A process of fabricating an electroactive assembly is disclosed. The process can include forming an electroactive assembly, where the electroactive assembly can include a first substrate, a second substrate, a laminate layer between the first substrate and the second substrate, and electroactive material between the first substrate and the second substrate; detecting a defect in the electroactive assembly; and laser ablating around the defect using at least two laser pulses in a pattern, where a first laser pulse is followed by a second laser pulse in succession, where the pattern can include a space between any two laser pulses being fired in succession, and where the pattern can include overlapping pulses between a pulse fired in a first circumferential pass and a pulse fired in a second circumferential pass.

Embodiment 18. The process of fabricating an electroactive assembly of embodiment 17, where forming the electroactive assembly can include: forming the first transparent conductive layer overlying the first substrate; forming at least one electroactive layer overlying the first transparent conductive layer, where the electroactive layer can include the electroactive material; forming the second transparent conductive layer; forming the laminate layer; and encapsulating the electroactive layer between the first substrate and the second substrate.

Embodiment 19. An electroactive laminate is disclosed. The electroactive laminate can include a first substrate; a second substrate; a first transparent conductive layer between the first substrate and the second substrate; a laminate layer between the first substrate and the second substrate; a second transparent conductive layer between the first substrate and the second substrate; an electroactive material between the first transparent conductive layer and the second transparent conductive layer; and at least one repaired area, where the at least one repaired area can include a circumferential continuous trench and where the trench has a double ring configuration formed by at least two individual laser spots.

Embodiment 20. The electroactive laminate of embodiment 19, where the trench has differing depths.

Embodiment 21. The electroactive laminate of embodiment 19, where the trench is non-uniform.

Embodiment 22. The electroactive laminate of embodiment 19, where the trench has varying widths.

Embodiment 23. The electroactive laminate of embodiment 19, where an area circumscribed by the trench is not delaminated.

Embodiment 24. The electroactive laminate of embodiment 19, where the repaired area further can include a defect within the repaired area and surrounded by the trench.

Embodiment 25. The electroactive laminate of embodiment 19, where the repaired area can include the substrate, the first transparent conductive layer, and the electroactive material at the bottom of the trench.

Embodiment 26. The electroactive laminate of embodiment 19, where the at least two individual laser spots are overlapping.

Embodiment 27. The electroactive laminate of embodiment 26, where a first distance from a center of the defect to a center of the first laser spot is different from a second distance from a center of the defect to a center of the second laser spot.

Embodiment 28. The electroactive laminate of embodiment 27, where each of the at least two individual overlapping laser spots are congruent.

Embodiment 29. The electroactive laminate of embodiment 19, where the electroactive material is a cathodic layer and can include material selected from the group consisting of WO3, V2O5, MoO3, Nb2O5, TiO2, CuO, Ni2O3, NiO, Ir2O3, Cr2O3, Co2O3, Mn2O3, mixed oxides (e.g., W—Mo oxide, W—V oxide), lithium, aluminum, zirconium, phosphorus, nitrogen, fluorine, chlorine, bromine, iodine, astatine, boron, a borate with or without lithium, a tantalum oxide with or without lithium, a lanthanide-based material with or without lithium, another lithium-based ceramic material, or any combination thereof.

Embodiment 32. The electroactive laminate of embodiment 19, where the electroactive material is a counter electrode layer that can include an inorganic metal oxide electrochemically active material, such as WO3, V2O5, MoO3, Nb2O5, TiO2, CuO, Ir2O3, Cr2O3, Co2O3, Mn2O3, Ta2O5, ZrO2, HfO2, Sb2O3,a lanthanide-based material with or without lithium, another lithium-based ceramic material, a nickel oxide (NiO, Ni2O3, or combination of the two), and Li, nitrogen, Na, H, or another ion, any halogen, or any combination thereof.