METHOD OF FORMING PHOSPHOR LAYER ON LIGHT-EMITTING DEVICE CHIP WAFER USING WAFER LEVEL MOLD

• US 20130183777A1
• Filed: 11/09/2012
• Published: 07/18/2013
• Est. Priority Date: 01/12/2012
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: LIM, Taeg-ki
• Application Number:
  US13/673,453
• Publication Number:
  US 20130183777A1
• Time in Patent Office: Days
• US Class Current: 438/27
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil

Abstract

A method of forming a phosphor layer of light-emitting device chip wafer by using a wafer level mold includes clamping a wafer having a plurality of light-emitting device chips between a lower mold and an upper mold to form a space between the wafer and the upper mold, forming a phosphor layer on the wafer by injecting a phosphor liquid into the space, and releasing the wafer from the lower mold and the upper mold.

Claims

1. A method of forming a phosphor layer of a light-emitting device chip wafer, the method comprising steps of:

clamping a wafer having a plurality of light-emitting device chips between a lower mold and an upper mold to form a space between the wafer and the upper mold;

forming a phosphor layer on the wafer by injecting a phosphor liquid into the space; and

detaching the wafer from the lower mold and the upper mold.

2. The method of claim 1, wherein the step of clamping of the wafer comprises covering electrodes of the light-emitting device chips with a plurality of rods extending from a ceiling of the upper mold.

3. The method of claim 2, further comprising forming a release layer on the upper mold before the clamping of the wafer, wherein the release layer facilitates the detachment of the wafer in the step of detaching the wafer.

4. The method of claim 2, further comprising steps of:

measuring a peak wavelength emitted from each of the light-emitting device chips of the light-emitting device chip wafer; and

adjusting distances from a ceiling of the upper mold to the corresponding upper surface of the light-emitting device chips according to the peak wavelength of the light-emitting device chips.

5. The method of claim 4, wherein the distances are reduced as the peak wavelength of the light-emitting device chip becomes larger.

6. The method of claim 2, wherein the covering electrodes of the light-emitting device chips covers entire upper surfaces of the electrodes.

7. The method of claim 1, further comprising steps of:

attaching a protection tape to the formed phosphor layer;

grinding a lower surface of the wafer to obtain a desired thickness of the wafer;

removing the protection tape;

placing the wafer on a dicing tape;

removing the phosphor layer between the plurality of semiconductor chips; and

separating the dicing tape from the wafer.

8. A method of forming a phosphor layer of a light-emitting device chip wafer by using a wafer level mold, the method comprising:

measuring peak wavelengths emitted from each of light-emitting device chips formed on a wafer;

mounting the wafer on a lower mold;

clamping an upper mold to the lower mold to form a space between the wafer and the upper mold;

forming a phosphor layer on the wafer by injecting a phosphor liquid into the space; and

releasing the wafer from the lower mold and the upper mold,

wherein distances from upper surfaces of the light-emitting device chips to a ceiling of the upper mold are adjusted according to the peak wavelength of the light-emitting device chips.

9. The method of claim 8, wherein the clamping comprises covering electrodes of the light-emitting device chips using a plurality of rods extending from a ceiling of the upper mold facing the lower mold.

10. The method of claim 8, further comprising forming a release layer on the upper mold before the clamping, wherein the release layer facilitates the release of the upper mold from the wafer in the step of releasing.

11. The method of claim 8, wherein the distances are reduced as the peak wavelength of the light-emitting device chip becomes larger.