Vacuum lamination method for forming a conformally coated article and associated conformally coated articles formed therefrom

Patent metadata

Field	Value
Publication number	US-10153409-B2
Application number	US-201515516772-A
Country	US
Kind code	B2
Filing date	Oct 21, 2015
Priority date	Oct 24, 2014
Publication date	Dec 11, 2018
Grant date	Dec 11, 2018

Abstract

Vacuum lamination methods for forming conformally coated articles having a preformed lamination layer conformally coated to or on an object such as an LED array are provided. These vacuum lamination methods utilize a single heating step to heat a middle portion of the preformed lamination layer to a flowable condition prior to the preformed lamination layer being conformally coated over the article, such as the array of light emitting diodes disposed on an inner portion of a first side of a submount wafer.

First claim

The invention claimed is:

1. A method of fabricating a conformally coated article from an assembly that is housed in a vacuum chamber of a fabrication device;
wherein the vacuum chamber contains an applied vacuum;
wherein the assembly comprises a preformed lamination layer and an object having a surface for lamination;
wherein the preformed lamination layer has a first surface and a second surface opposite the first surface, and a heat-softened middle portion at a first temperature and surrounded by an edge portion;
wherein the object has a first surface and a second surface opposite the first surface, and the first surface being in need of lamination and comprising an inner portion and a perimeter portion surrounding the inner portion;
wherein the assembly is configured such that the first surface of the preformed lamination layer is positioned facing the first surface of the object, wherein the edge portion of the preformed lamination layer forms a gastight seal to the perimeter portion of the first surface of the object such that the assembly contains a gastight inner region defined by a combination of the gastight seal, the first surface of the preformed lamination layer and the first surface of the object, wherein the heat-softened middle portion of the preformed lamination layer is spaced apart from the inner portion of the first surface of the object by the gastight inner region, and wherein the gastight inner region contains a reduced gas pressure;
wherein the applied vacuum in the vacuum chamber is effectively equal to the reduced gas pressure in the gastight inner region of the assembly; and
said method comprising:
conforming the heat-softened middle portion of the preformed lamination layer to the inner portion of the first surface of the object by increasing gas pressure within the vacuum chamber such that the gas pressure within the vacuum chamber is greater than the reduced gas pressure within the gastight inner region, thereby conformally pushing the heat-softened middle portion against the inner portion of the first surface of the object so as to fabricate the conformally coated article;
wherein the conformally coated article comprises a conformed lamination layer and the object, wherein the conformed lamination layer is formed from the preformed lamination layer and has a first surface and a second surface opposite the first surface, and a middle portion and an edge portion surrounding the middle portion; wherein the object has a first surface having an inner portion and a perimeter portion surrounding the inner portion, wherein the inner portion of the first surface of the object is conformally coated by the middle portion of the conformed lamination layer; and wherein the edge portion of the conformed lamination layer forms a gastight seal to the perimeter portion of the first surface of the object,
wherein the middle portion of the preformed lamination layer is heated in only one heating step.

2. The method of claim 1 wherein in the conforming step the gas pressure is increased within the vacuum chamber by breaking the applied vacuum in the vacuum chamber of the fabrication device and allowing a gas to enter the vacuum chamber.

3. The method of claim 2 further comprising, prior to the sealing step, heating, under the applied vacuum, the edge portion of the preformed lamination layer to the second temperature to form the heat-softened edge portion of the preformed lamination layer.

4. The method of claim 3 further comprising, prior to the heating step, applying a vacuum within the vacuum chamber to remove gas from the vacuum chamber, including from between the first surface of the preformed lamination layer and the first surface of the object, so as to create the applied vacuum in the vacuum chamber of the fabrication device.

5. The method of claim 4 further comprising, prior to the applying step, introducing the preformed lamination layer and the object into the vacuum chamber of the fabrication device; and prior to, during or after the introducing step, mounting the preformed lamination layer against the object such that the first surface of the preformed lamination layer is positioned facing the first surface of the object; wherein the preformed lamination layer used in the mounting step is coupled to a support layer and wherein the method further comprises, after the mounting step and prior to the introducing step: Adhering a first subportion of the edge portion of the preformed lamination layer to a first subportion of the perimeter portion of the first surface of the object without adhering a second subportion of the edge portion of the preformed lamination layer to a second subportion of the perimeter portion of the first surface of the object, wherein the adhering step is performed while the preformed lamination layer is coupled to the support layer; and Removing, after the adhering step, the support layer from the mounted preformed lamination layer.

6. The method of claim 1 or 2 further comprising, prior to the conforming step, sealing, under the applied vacuum, the edge portion of the preformed lamination layer to the perimeter portion of the first surface of the object by contacting the edge portion of the preformed lamination layer to the perimeter portion of the first surface of the object so as to form the gastight seal and the gastight inner region of the assembly, wherein during the contacting the edge portion of the preformed lamination layer is characterized by being heat-softened at a second temperature, wherein the first and second temperatures are the same or different.

7. The method of claim 6 wherein the sealing step comprises pressing the heat-softened edge portion of the preformed lamination layer to the perimeter portion of the first surface of the object.

8. The method of claim 6 further comprising, prior to the sealing step, the actions of:
heating a portion of the edge portion to the second temperature to soften the portion of the edge portion of the preformed lamination layer while maintaining the middle portion of the preformed lamination layer and another portion of the edge portion at a temperature below the first temperature; and
pressing the softened portion of the edge portion to the perimeter portion until adhesion is obtained between the first surface of the softened edge portion of the preformed lamination layer and the perimeter portion; and
wherein adhesion is not obtained between the another portion of the edge portion such that the gastight inner region is not created.

9. The method of claim 6 , wherein the preformed lamination layer is not adhered to a support layer during or subsequent to the sealing step or any adhering step.

10. The method of claim 1 further comprising, prior to the conforming step, heating, under the applied vacuum, the middle portion of the preformed lamination layer to the first temperature to soften the middle portion of the preformed lamination layer to form the heat-softened middle portion of the preformed lamination layer.

11. The method of claim 10 wherein the fabrication device further includes a first heater device, which is positioned adjacent to the second surface of the object in such a way that any thermal communication between the first heater and the second surface of the object is insufficient to soften the preformed lamination layer; and
wherein the heating step comprises:
moving the second surface of the object into thermal communication with the first heater device, or vice versa; and
activating the first heater device so that it produces heat;
wherein the activated first heater device heats the object, which consequently heats the preformed lamination layer to the first temperature

Assignees

• Dow Silicones Corp

Inventors

• Cummings Michelle R
• Nishida Fumito
• Shephard Nick E

Classifications

• H10W90/00 Primary

  Package configurations · CPC title

• H10W72/0198

  batch processes · CPC title

• B32B2307/732

  Dimensional properties · CPC title

• B32B3/28

  characterised by a layer comprising a deformed thin sheet {, i.e. the layer having its entire thickness deformed out of the plane}, e.g. corrugated, crumpled (B32B29/08 takes precedence) · CPC title

• B32B27/38

  comprising epoxy resins · CPC title