Method of manufacturing an optoelectronic device

Abstract

Disclosed is a method of making an optoelectronic device that incorporates a crosslinked resin-linear polyorganosiloxane.

Claims

1. A method of manufacturing an optoelectronic device comprising: i) providing a substrate wherein the substrate comprises one or more electro-optic component arranged on at least one surface of the substrate; ii) contacting the surface of the electro-optic component parallel to the substrate with a lateral filler film comprising a filler and a curable silicone hot melt; iii) contacting the lateral filler film with a release liner; and iv) applying pressure to the lateral filler film, and v) removing a residue that is formed on the top surface of the electro-optic component, to create the optoelectronic device.

2. The method of claim 1 wherein the electro-optic component is a light emitting diode.

3. The method of claim 1 wherein the curable silicone hot melt is a crosslinkable resin-linear polyorganosiloxane formulation.

4. The method of claim 1 wherein the lateral filler film is uncured prior to applying pressure.

5. The method of claim 1 wherein the filler comprises a compound selected from the group consisting of TiO.sub.2, BN, SiO.sub.2, Al.sub.2O.sub.3, ZnO, BaSO.sub.4, and mixtures thereof.

6. The method of claim 1 wherein the residue is removed by wiping with a solvent.

7. The method of claim 1 wherein the solvent comprises isopropyl alcohol, acetone, heptane, octane, propylpropionate, toluene, and mixtures thereof.

8. An optoelectronic device manufactured by the method of claim 1.

9. The method of claim 1 wherein the electro-optic component is an LED chip, and wherein after pressure is applied, a residue is formed on the top surface of the LED chip and is further removed.

10. The method of claim 1 wherein the thickness of the lateral filler film is arranged to the same or less as the height of the electro-optic component from the surface of the substrate prior to contacting it to the surface of the electro-optic component.

11. A method of manufacturing an optoelectronic device comprising: i) providing a substrate wherein the substrate comprises one or more electro-optic component arranged on at least one surface of the substrate, ii) contacting the surface of the electro-optic component parallel to the substrate with a lateral filler film comprising a filler and a curable silicone hot melt; iii) contacting the lateral filler film with a release liner; iv) applying pressure to create the optoelectronic device; v) applying a wavelength conversion layer on top of the created optoelectronic device; and vi) curing simultaneously.

12. An optoelectronic device manufactured by the method of claim 11.

Description

EXAMPLES

(1) Resin Used

(2) TABLE-US-00001 Resin A: Dow Corning LF-1201 Commercially available from Dow Phosphor Film Binder Corning Toray, Chiba, Japan and equivalent to LF-1113 available from the same supplier Resin B: Dow Corning LF-1200 Commercially available from Dow Phosphor Film Binder Corning Toray, Chiba, Japan and equivalent to LF-1112 available from the same supplier

Lateral Filler Film Preparation

Example 1

(3) 53.4 g of Resin A, 5.39 g of Showa Denko boron nitride powder UHP-S1 (0.5 umD), and 2.86 g propylpropionate was added to a mixing container. These components were hand mixed for 2 minutes, followed by 1200 rpm/2 min/without vacuum using Thinky ARV-310 LED×2 times. The mixture was further mixed at 1200 rpm/30 sec/10 kPa (i.e., under vacuum) then 600 rpm/30 sec/5 kPa. The slurry was coated onto a siliconized PET using a flame applicator with 491 um gap, and heated to dry the film using an oven with temperature at 70° C. for 30 minutes. The resulting film was 197 um thick. The reflectivity at 450 nm was 81.6%, measured using Konica Minolta CM-5.

Example 2

(4) 34.7 g of Resin A, 17.3 g of Sakai Chem titania powder SX-3103 (0.2 umD), and 2.0 g propylpropionate was added to a mixing container. These components were mixed at 2000 rpm/2 min without vacuum using Thinky ARV-310×2 times. The mixture was further mixed at 2000 rpm/30 sec/10 kPa (i.e., under vacuum) then 800 rpm/30 sec/5 kPa. The slurry was coated on siliconized PET using a comma coater with 324 um gap, and heated to dry the film using 1.2 m oven with temperature gradually increasing from 60° C. to 100° C. The resulting film was 139 um thick. The reflectivity at 450 nm was 96.6%, measured using Konica Minolta CM-5.

Example 3

(5) 3.175 g of Momentive PT120P001 boron nitride (D50=12 um; D90=20 um) was added to 10 g of Resin A. Mixture was mixed three times in FlackTek DAC 150 VAC-P speed mixer for 30 sec at 2000 rpm with hand mixing between the first and the second mix. Additional mixing was done under vacuum (reaches below 200 mm Hg) at 1500 rpm for 60 sec. The resulting slurry was coated on siliconized PET (Mitsubishi Polyester 2SLKN) using table top automatic coater then dried at 70° C. for 60 min yielding 152 μm thick film.

Lateral Filler Film Lamination and Residue Removal Process

Example 4

(6) Film material fabricated in Example 2 was placed on an array of LEDs with their chip height 150 μm. This stack was placed in Imoto Vacuum press IMC-4C05 with both upper and lower plates temperature set at 100° C. then covered with a sheet of fluorosiliconized PET (Takara incorporation FL2-01 #75). System was evacuated for 1 min during which the vacuum reached 0.04 kPa, then compress under vacuum for 60 sec applying 1 kN at device temperature 100° C. The resulting laminate having 152 μm thick total was removed from the press and release linear peeled showing LED arrays with thin residual white materials. Residue was removed by hand wipe using isopropyl alcohol (IPA) moistened clean room cloth exposing clean surface of LED chips filled with white reflector.

Example 5

(7) Film material fabricated in Example 1 was first compressed at 50° C. to make 150 μm thick film. The obtained film was placed on an array of LEDs with their chip height 150 μm. This stack was placed in Imoto Vacuum press IMC-4C05 with the upper plate heated to 100° C., and lower plate kept lower than 30° C. using water circulation, then covered with a sheet of fluorosiliconized PET (Takara Incorporation, FL2-01 #75). System was evacuated for 1 min during which the vacuum reached 0.04 kPa, then compress under vacuum for 60 sec applying 1 kN at device temperature 72° C. The resulting laminate having 151 μm thick total was removed from the press and release linear peeled showing LED arrays with thin residual white materials. Residue was removed by hand wipe using isopropyl alcohol (IPA) moistened clean room cloth exposing clean surface of LED chips filled with white reflector.

Comparable Example 1

(8) Film material fabricated in Example 1, with 197 μm thick was placed on an array of LEDs with their chip height 150 μm. This stack was placed in Imoto Vacuum press IMC-4C05 with the upper plate heated to 100° C., and lower plate kept lower than 30° C. using water circulation, then covered with a sheet of fluorosiliconized PET (Takara Incorporation, FL2-01 #75). System was evacuated for 1 min during which the vacuum reached 0.04 kPa, then compress under vacuum for 60 sec applying 1 kN at device temperature 72° C. The resulting laminate having 187 μm thick total was removed from the press and release linear peeled showing LED arrays with thin residual white materials. The residue with 47 μm thick was not able to be removed by hand wipe using isopropyl alcohol (IPA) moistened clean room cloth exposing clean surface of LED chips.

(9) Therefore, either compressing the material to the close height of the LED chip under higher temperatures or higher pressures, or the original film thickness should be close to the LED heights.

Example 6

(10) Film material fabricated in Example 3 was placed on an array of LEDs. This stack was placed on a sample holder for a vacuum laminator (in-house custom made tool) with hot plate temperature set at 140° C. LED array/white film stack was covered with a sheet of siliconized PET (Mitsubishi Polyester 2SLKN) then placed a small piece of aluminum block (about 5 cm×5 cm×1 cm) and a plate (3″×5″×¼″) with a total weight of 316 g on the film. The laminator was evacuated for 60 sec during which the vacuum reached about 28.5″ Hg while the sample stayed raised above the hot plate by about a mm. Bladder was used to press the aluminum block/plate which in turn pushed the entire LED substrate/film/liner assembly on to the hot plate heating the substrate/white film stack for 30 sec. Pressure differential in chamber above and below bladder was about 10″ Hg. The resulting sample showed very thin layer of residual material covering the surface of LED chips which could be removed with several wipes using heptane moistened cleanroom wipe.

(11) Adhesion Between Lateral Filler Film (BN Film) and Wavelength Conversion Layer (Phosphor Film):

Example 7

(12) 30.407 g of NYAG-4454S (Intematix) and 0.751 g of propylpropionate was added to 18 g of Resin B. Mixture was mixed three times in FlackTek DAC 150 VAC-P speed mixer for 30 sec at 2000 rpm with hand mixing between the first and the second mix. Additional mixing was done under vacuum (reaches below 200 mm Hg) at 1500 rpm for 60 sec. The resulting slurry was coated on siliconized PET (Mitsubishi Polyester 2SLKN) using table top automatic coater then dried at 70° C. for 60 min yielding 50 am thick phosphor film.

(13) 6.984 g of boron nitride (BN)(PCTP2; Saint Goban) and 2.40 g of propylpropionate was added to 22 g of Resin A. Mixture was mixed three times in FlackTek DAC 150 VAC-P speed mixer for 30 sec at 2000 rpm with hand mixing between the first and the second mix. Additional mixing was done under vacuum (reaches below 200 mm Hg) at 1500 rpm for 60 sec. The resulting slurry was coated on siliconized PET (Mitsubishi Polyester 2SLKN) using table top automatic coater then dried at 90° C. for 90 min yielding 150 μm thick BN film.

(14) Phosphor film and BN film were each cut to 1″×1″ sheets and laminated on to separate aluminum plates (1×25×75 mm). 4 aluminate plates laminated with BN film were cured at 160° C. for 1 hour to obtained “cured BN film” (5 were left uncured). Al plates with uncured phosphor films were assembled with Al plates with BN films such that phosphor film and BN film overlapped completely and held together with a pair of clips. These assemblies were cured 16 hrs. at 160° C. to fabricate a lap shear test specimens. Test specimens were pulled on Instron Model 5566 at 2 in/min to measure tensile strength. Adhesion failure modes were also noted and summarized in Table 1. Precured BN film specimens (i.e., uncured phosphor film+cured BN film) measured lower tensile strength and all showed adhesive failure between the two films. When BN and phosphor films are cured simultaneously (i.e., uncured phosphor film+uncured BN film), tensile strength was higher and failure occurred either cohesively or adhesive failure between the phosphor film and the substrate (i.e., no adhesive failure between the two films) thereby indicating improvement in adhesion between the two layers.

(15) TABLE-US-00002 TABLE 1 Film Tensile Strength (psi) typical % adhesive BN Phosphor n Avg StdDev failure btw films Cured Uncured 4 673 61 90 Uncured Uncured 5 1000 19 0

Adhesion of Lateral Filler Film (TiO.SUB.2 .White Film) and Wavelength-Conversion Layer (Phosphor Film) Measured Through Die Shear Test

Example 8

(16) 5.487 g of TiO.sub.2 (SX-3103; Sakai Chem) and 1.01 g of propylpropionate was added to 10.91 g of Resin B. Mixture was hand mixed for 2 minutes, followed by 1200 rpm/2 min without vacuum using Thinky ARV-310LED×2 times. The mixture was further mixed at 1200 rpm/30 sec/10 kPa (i.e., under vacuum) then 600 rpm/30 sec/5 kPa. The resulting slurry was casted on Al plate (1×25×75 mm) with Teflon PSA dam (180 μm thickness). 90 μm thick uncured TiO.sub.2 layer was obtained by drying 30 min at 70° C. (#4225 Uncured). 90 μm thick cured TiO.sub.2 layer was obtained by drying 30 min at 70° C. followed by heating at 120° C. for 1 hr. then 160° C. for 2 hr. (#4225 Cured).

(17) 33.303 g of TiO.sub.2 (SX-3103; Sakai Chem) and 5.04 g of propylpropionate was added to 10.78 g of Resin A. Mixture was hand mixed for 2 minutes, followed by 1200 rpm/2 min/without vacuum using Thinky ARV-310LED×2 times. The mixture was further mixed at 1200 rpm/30 sec/10 kPa (i.e., under vacuum) then 600 rpm/30 sec/5 kPa. The resulting slurry was casted on Al plate (1×25×75 mm) with Teflon PSA dam (180 um thickness). 90 μm thick uncured TiO.sub.2 layer was obtained by drying 30 min at 70° C. (#4226 Uncured). 90 μm thick cured TiO.sub.2 layer was obtained by drying 30 min at 70° C. followed by heating at 120° C. for 1 hr. then 160° C. for 2 hr. (#4226 Cured).

(18) 5.323 g of NYAG-4454L (Intematix, YAG phosphor, 13 μm diameter) and 1.01 g of propylpropionate was added to 10.88 g of Resin B. Mixture was hand mixed for 2 minutes, followed by 1200 rpm/2 min/without vacuum using Thinky ARV-310LED×2 times. The mixture was further mixed at 1200 rpm/30 sec/10 kPa (i.e., under vacuum) then 600 rpm/30 sec/5 kPa. The slurry was coated on siliconized PET using 750 um gap, followed by 70° C. for 2 hours to prepare 290 μm thick film (#4227).

(19) 8 mm diameter 290 umT #4227 phosphor film was punched out and placed on respective TiO.sub.2 layer. 1×10×10 mm Al chips were then placed on the phosphor film making Al chip/Phosphor film/TiO.sub.2 layer/Al plate structure. Another set was made by placing phosphor film directly on the aluminum plate then Al chip (i.e., without TiO.sub.2 layer: Al/Phosphor film/Al plate). All samples were cured at 120° C./1 hr+160° C./2 hr. Al chips were sheared to measured die shear strength and the result showed improved adhesion strength when TiO.sub.2 layer is present and more so when TiO.sub.2 and phosphor layers were cured together (i.e., when TiO.sub.2 layer was uncured prior to cure of the entire assembly).

(20) TABLE-US-00003 TABLE 2 Die Shear Test structure Al chip Al chip 4227 4227 Al chip Al chip 4225(un- 4226(un- 4227 4227 Al chip cured) cured) 4225(cured) 4226(cured) 4227 Al plate Al plate Al plate Al plate Al plate (Avg. 25.68 28.29 23.74 27.49 11.1 Force) (kg) (Strength) 404 445 373 432 175 N/cm.sup.2