Light emitting device and method of manufacture
A light emitting device is manufactured by forming a light emitting structure upon a buffer layer formed on a substrate. The light emitting structure is then separated from the buffer layer and the substrate. A light-directing element such as a mirror or a lens is then attached to the light emitting structure using a bonding agent.
1 . A light emitting device comprising:
a light emitting structure comprising an active layer formed of In x Al y Ga 1-x-y N;
a bonding agent applied to a major surface of the light emitting structure; and
a light-directing element attached by the bonding agent to the major surface of the light emitting structure.
2 . The light emitting device of claim 1 , wherein:
the light emitting structure is a first unit of manufacture; and
the light-directing element is a second unit of manufacture independent of the first unit of manufacture.
3 . The light emitting device of claim 2 , wherein:
the light emitting structure is manufactured using metalorganic chemical vapor phase epitaxy (MOVPE) process; and
the light-directing element is manufactured using a process other than MOVPE.
4 . The light emitting device of claim 3 , wherein the bonding agent comprises an optical-quality epoxy bond.
5 . The light emitting device of claim 4 , wherein the light-directing element is a mirror.
6 . The light emitting device of claim 5 , wherein light generated in the active layer is reflected by the mirror and is transmitted out of the light emitting device after traversing the bonding agent and the light emitting structure.
7 . The light emitting device of claim 4 , wherein the light-directing element is a lens.
8 . The light emitting device of claim 7 , wherein light generated in the active layer is transmitted out of the light emitting device after traversing the bonding agent and a portion of the light emitting structure.
9 . The light emitting device of claim 3 , wherein the light emitting device is a vertical cavity surface emitting laser (VCSEL).
10 . The light emitting device of claim 9 , wherein the major surface of the light emitting structure is a major surface of a cladding layer that is located adjacent to the active layer of the light emitting structure.
11 . The light emitting device of claim 9 , wherein the major surface of the light emitting structure is a major surface of one of a current conduction layer and a contact layer.
12 . A method for a light emitting device, the method comprising:
providing a substrate with a buffer layer formed on the substrate;
forming on the buffer layer, a light emitting structure comprising an active region;
separating the light emitting structure from the buffer layer and the substrate;
providing a light-directing element;
providing a bonding agent; and
attaching the light-directing element to the light emitting structure using the bonding agent.
13 . The method of claim 12 , wherein the active region comprises In x Al y Ga 1-x-y N.
14 . The method of claim 12 , wherein separating the light emitting element structure from the buffer and the substrate comprises using a laser liftoff process.
15 . The method of claim 12 , wherein the bonding agent is an optical epoxy bond.
16 . The method of claim 15 , wherein the light emitting structure is formed on the buffer layer using a metalorganic chemical vapor phase epitaxy (MOVPE) process.
17 . The method of claim 16 , wherein the light-directing element is one of a) a lens, b) a mirror, c) a grating, and d) an optical filter element.
18 . The method of claim 17 , wherein the light-directing element is manufactured using a process other than MOVPE.
19 . The method of claim 12 , wherein attaching the light-directing element to the light emitting structure comprises attaching the light-directing element to a cladding layer of the light emitting structure.
20 . The method of claim 12 , wherein attaching the light-directing element to the light emitting structure comprises attaching the light-directing element to one of a current conduction layer and a contact layer of the light emitting structure.