Optical device processing method

• US 8,945,960 B2
• Filed: 06/04/2013
• Issued: 02/03/2015
• Est. Priority Date: 06/12/2012
• Status: Active Grant

• Current Assignee: Disco Corporation
• Original Assignee: Disco Corporation
• Inventors: Sekiya, Kazuma
• Primary Examiner(s): Maldonado, Julio J
• Assistant Examiner(s): BACHNER, ROBERT G
• Application Number:
  US13/909,766
• Publication Number:
  US 20130330856A1
• Time in Patent Office: 609 Days
• Field of Search: 438/26, 438/42, 438/27, 438/33
• US Class Current: 438/33
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

An optical device wafer has a plurality of optical devices formed on a front side and a plurality of crossing division lines for partitioning the optical devices. Each optical device has electrodes formed on the front side. A processing method includes: forming a groove on the front side of the wafer along each division line, the groove having a depth reaching a finished thickness; of forming a nonconductive reflective film on the front side of the wafer to thereby form the reflective film on at least the side surfaces of the groove; removing the reflective film formed on the electrodes to thereby expose the electrodes; and grinding a back side of the wafer to thereby reduce the thickness to the finished thickness until the groove is exposed to the back side of the wafer to divide the wafer into individual optical device chips.

Claims

1. An optical device processing method for processing an optical device wafer having a plurality of optical devices formed on a front side and a plurality of crossing division lines for partitioning the optical devices, each of the optical devices having electrodes formed on the front side, the optical device processing method comprising:

a groove forming step of forming a groove on the front side of the optical device wafer along each division line, the groove having a depth reaching a finished thickness;

a reflective film forming step of forming a nonconductive reflective film on the front side of the optical device wafer after performing the groove forming step, thereby forming the reflective film on at least side surfaces of the groove;

an electrode exposing step of removing the reflective film formed on the electrodes on the front side of the optical device wafer after performing the reflective film forming step, thereby exposing the electrodes; and

a grinding step of grinding a back side of the optical device wafer before or after performing the electrode exposing step, thereby reducing the thickness of the optical device wafer to the finished thickness until the groove is exposed to the back side of the optical device wafer to divide the optical device wafer into individual optical device chips.

2. The optical device processing method according to claim 1, wherein

the reflective film is formed over the entire surface on the front side of the optical device wafer in the reflective film forming step;

and

the reflective film formed on the front side of the optical device wafer is cut off by using tool cutting means to thereby expose the electrodes in the electrode exposing step.

3. The optical device processing method according to claim 1, further comprising:

a mounting step of flip-chip mounting each optical device chip on a substrate after performing the grinding step; and

a sealing step of sealing each optical device chip mounted on the substrate with a sealing member.