Manufacturing method of light-emitting diode

• US 8,193,014 B2
• Filed: 01/27/2010
• Issued: 06/05/2012
• Est. Priority Date: 01/27/2009
• Status: Active Grant

• Current Assignee: Citizen Watch Co Limited (Citizen Electronics Company Limited)
• Original Assignee: Citizen Electronics Company Limited, Citizen Holdings Co., Ltd.
• Inventors: Horiuchi, Megumi
• Primary Examiner(s): Garber, Charles
• Assistant Examiner(s): MUSTAPHA, ABDULFATTAH B
• Application Number:
  US12/694,382
• Publication Number:
  US 20100190280A1
• Time in Patent Office: 860 Days
• Field of Search: 438/22, 438/28, 257/E33.056, 257/E33.001, 257/E25.02, 313/498
• US Class Current: 438/28
• CPC Class Codes: H01L 21/6836 Wafer tapes, e.g. grinding or dicing support tapes adhesive tapes in general C09J7/20
• CPC Class Codes: H01L 2221/68336 involving stretching of the auxiliary support post dicing
• CPC Class Codes: H01L 2221/68354 used to support diced chips prior to mounting
• CPC Class Codes: H01L 2221/68377 with parts of the auxiliary support remaining in the finished device
• CPC Class Codes: H01L 2224/0554 External layer
• CPC Class Codes: H01L 2224/0555 Shape
• CPC Class Codes: H01L 2224/0556 Disposition
• CPC Class Codes: H01L 2224/05568 the whole external layer protruding from the surface
• CPC Class Codes: H01L 2224/05573 Single external layer
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2224/81 using a bump connector
• CPC Class Codes: H01L 2224/81205 Ultrasonic bonding
• CPC Class Codes: H01L 2224/81801 Soldering or alloying
• CPC Class Codes: H01L 2224/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 24/11 Manufacturing methods for bumps on insulating substrates H01L21/4853
• CPC Class Codes: H01L 24/13 of an individual bump connector
• CPC Class Codes: H01L 24/81 using a bump connector
• CPC Class Codes: H01L 24/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01015 : Phosphorus [P]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01075 : Rhenium [Re]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/01322 : Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2933/0041 : relating to wavelength conversion elements
• CPC Class Codes: H01L 33/005 : Processes
• CPC Class Codes: H01L 33/486 : adapted for surface mounting
• CPC Class Codes: H01L 33/54 : having a particular shape
• CPC Class Codes: H01L 33/62 : Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

A manufacturing method of an LED comprises attaching an LED epitaxial wafer (LED wafer) to an expanding tape, dicing the LED wafer on the expanding tape longitudinally and laterally to a certain element size to divide into a plurality of LED elements, expanding the expanding tape to a certain size to form an enlarged expanding tape, placing respective pairs of element electrodes of the plurality of LED elements that are attached to the enlarged expanding tape on respective pairs of electrodes on a printed-circuit board assembly collectively to perform a bonding, and removing the enlarged expanding tape from the plurality of the LED elements.

Claims

1. A manufacturing method of light-emitting diode, comprising:

an attaching-wafer-to-tape step;

attaching a first surface of a light-emitting diode epitaxial wafer to an expanding tape, the first surface being opposite to a second surface of the wafer, and the second surface being provided with a plurality of element electrodes,

a dicing-wafer-step;

dicing the wafer longitudinally and laterally to form a plurality of light-emitting diode elements each of a certain size with a pair of the element electrodes, in a state that each of the light-emitting diode elements is attached to the expanding tape,

an expanding-tape step;

expanding the expanding tape in a state that each of the diced light-emitting diode elements is attached to the expanding tape, thereby forming a certain space between one another of the diced light-emitting diode elements,

a bonding-electrodes step;

laying the expanded expanding tape with the plurality of light-emitting diode elements attached over a plurality of pairs of electrodes that are disposed on a printed-circuit board assembly, to electrically dispose each pair of the element electrodes of the plurality of light-emitting diode elements on each pair of the plurality of pairs of electrodes disposed on the printed-circuit board assembly, such that each pair of the element electrodes of the plurality of light-emitting diode elements faces and is bonded to each pair of electrodes disposed on the printed-circuit board assembly; and

a removing-tape step;

removing the expanding tape from the light-emitting diode elements each bonded to the corresponding pair of the electrodes on the printed-circuit board.

2. The manufacturing method of light-emitting diode according to claim 1,

wherein the bonding at the bonding-electrodes step is a provisional bonding performed with a bonding strength that allows the subsequent removing-tape step in a state that the each pair of the light-emitting diode elements are kept bonded to the each corresponding pair of the electrodes on the printed-circuit board assembly,

and further comprising:

a main bonding step;

bonding firmly the each pair of the element electrodes of the plurality of light-emitting diode elements to the each corresponding pair of the electrodes on the printed-circuit board assembly, subsequent to the removing-tape step.

3. The manufacturing method of light-emitting diode according to claim 1,

wherein at the bonding-electrodes step, the each pair of the element electrodes of the light-emitting diode elements and the each corresponding pair of the electrodes on the printed-circuit board assembly are collectively bonded at one time.

4. The manufacturing method of light-emitting diode according to claim 1, further comprising:

a forming-light-transmitting-resin step;

forming a light-transmitting resin portion that collectively covers the plurality of light-emitting diode elements on the printed-circuit board assembly, subsequent to the removing-tape step, and

a full-cut dicing step;

full-cut dicing the light-transmitting resin portion and the printed-circuit board assembly longitudinally and laterally to divide into a plurality of individual light-emitting diodes.

5. The manufacturing method of light-emitting diode according to claim 1,

wherein, at the electrodes-bonding step, an anode electrode and a cathode electrode of the each pair of the element electrodes are bonded to an anode electrode and a cathode electrode of the each pair of the electrodes on the printed-circuit board assembly by a pair of bumps.

6. The manufacturing method of light-emitting diode according to claim 1, further comprising:

a forming-light-transmitting-resin step;

disposing the light-transmitting sheet that includes a fluorescent material on upper surfaces of the light-emitting diode elements, and then heating the light-transmitting sheet that includes the fluorescent material to melt to cover the upper surfaces and side surfaces of the light-emitting diode elements to form a fluorescent light-transmitting layer on the upper surfaces and side surfaces of the light-emitting diode elements, and

a full-cut dicing step;

full-cut dicing the light-transmitting layer and the printed-circuit board assembly longitudinally and laterally to divide into a plurality of light-emitting diodes.