LED DEVICE AND MANUFACTURING METHOD THEREOF

• US 20150311405A1
• Filed: 11/25/2013
• Published: 10/29/2015
• Est. Priority Date: 12/10/2012
• Status: Active Grant

• Current Assignee: Citizen Watch Co Limited (Citizen Electronics Company Limited)
• Original Assignee: Citizen Electronics Company Limited, Citizen Holding Co., Ltd.
• Inventors: Oyamada, Nodoka, Imazu, Kenji, Mochizuki, Shusaku
• Granted Patent: US 9,490,398 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 2224/13 of an individual bump connector
• CPC Class Codes: H01L 2933/0033 relating to semiconductor body packages
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 2933/0058 relating to optical field-shaping elements
• CPC Class Codes: H01L 33/36 characterised by the electrodes
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/50 Wavelength conversion elements
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

Provided is an LED device which is compact while having good luminous efficiency and a focused light distribution. This LED device is provided with: a reflective frame around the outer periphery of the LED device; an LED die which has a transparent insulating substrate, a semiconductor layer formed on the bottom surface of the transparent insulating substrate, and an outer connection electrode disposed on the semiconductor layer; and a fluorescent member which is disposed on at least the top surface of the LED die and which converts the wavelength of the light emitted from the LED die. On the inside of the reflective frame is an inclined surface in contact with the lateral surface of the fluorescent member, and the inclined surface is formed such that the inner diameter of the reflective frame widens from the bottom surface towards the top surface of the LED die. Also provided is a manufacturing method of the LED device.

Claims

1. An LED device comprising:

a reflective frame formed around an outer periphery of said LED device;

an LED die having a transparent insulating substrate, a semiconductor layer formed on a lower surface of said transparent insulating substrate, and an external connecting electrode formed on said semiconductor layer; and

a phosphor member, disposed at least on an upper side of said LED die, for wavelength-converting light emitted from said LED die,

wherein an inner wall of said reflective frame is provided with a sloping face which in contact with a side face of said phosphor member, and

said sloping face is formed so that an inside diameter of said reflective frame becomes larger from a lower side of said LED die toward the upper side thereof.

2. The LED device according to claim 1, wherein a bottom face on the lower side of said LED die and a lowermost end of said sloping face on the lower side of said LED die are at substantially the same position, and said phosphor member is disposed in a gap created between said sloping face and a side face of said LED die.

3. The LED device according to claim 1, wherein a bottom face on the lower side of said LED die and a lowermost end of said sloping face on the lower side of said LED die are at substantially the same position, and an optically transmissive member or another phosphor member other than said phosphor member is disposed in a gap created between said sloping face and a side face of said LED die.

4. The LED device according to claim 1, wherein said phosphor member is a phosphor sheet, and said phosphor sheet is bonded to an upper face of said LED die.

5. The LED device according to claim 1, wherein said reflective frame is formed from a reflective resin.

6. The LED device claim 1, wherein the bottom face on the lower side of said LED die is covered with said reflective resin except a region where said external connecting electrode is formed.

7. The LED device according to claim 1, wherein the inner wall of said reflective frame is provided with a planar portion in addition to said sloping face, and said planar portion covers a side face of said LED die.

8. The LED device according to claim 1, wherein the inner wall of said reflective frame is provided, on the upper side of said LED die, with a face formed perpendicular to the bottom face on the lower side of said LED die, and

the inner wall of said reflective frame is provided, on the lower side of said LED die, with said sloping face.

9. A method for manufacturing an LED device having a reflective frame formed around an outer periphery thereof, an LED die, and a phosphor member for wavelength-converting light emitted from said LED die, the method comprising:

a placement step for placing said LED die on a first support sheet in such a manner that an external connecting electrode provided on a lower side of said LED die faces down;

a phosphor member applying step for applying said phosphor member so as to cover upper and side faces of said LED die;

a groove forming step for bonding a second support sheet to an upper surface of said phosphor member on an upper side of said LED die and for forming a groove for separating said LED die by applying a V-shaped blade from a bottom side of said phosphor member;

a reflective resin filling step for filling a reflective resin into said groove; and

a dicing step for dicing to separate said LED device by cutting said reflective resin.

10. The LED device manufacturing method according to claim 9, wherein in said groove forming step, first a groove having a rectangular cross section is formed in said phosphor member, and then said V-shaped blade is applied from the bottom side of said phosphor member to form a sloping face on a portion of said rectangular cross-section groove, thereby forming a groove that has a sloping face on said bottom side.

11. A method for manufacturing an LED device having a reflective frame formed around an outer periphery thereof, an LED die, and a phosphor member for wavelength-converting light emitted from said LED die, the method comprising:

a placement step for placing said LED die on a large-sized phosphor sheet in such a manner that an external connecting electrode provided on a lower side of said LED die faces down;

an optically transmissive member filling step for filling an optically transmissive member or a phosphor member different from said phosphor sheet into a gap separating said LED die;

a groove forming step for forming a groove for separating said LED die by applying a V-shaped blade so as to cut through said optically transmissive member or said phosphor member different from said phosphor sheet until reaching said phosphor sheet;

a reflective resin filling step for filling a reflective resin into said groove; and

a dicing step for dicing to separate said LED device by cutting said reflective resin.