WAVELENGTH CONVERTED LIGHT EMITTING DEVICE WITH SMALL SOURCE SIZE
A lighting structure according to embodiments of the invention includes a semiconductor light emitting device and a flat wavelength converting element attached to the semiconductor light emitting device. The flat wavelength converting element includes a wavelength converting layer for absorbing light emitted by the semiconductor light emitting device and emitting light of a different wavelength. The flat wavelength converting element further includes a transparent layer. The wavelength converting layer is formed on the transparent layer.
1 . A lighting structure comprising:
a semiconductor light emitting device deposited on a die;
a substantially flat wavelength converting element attached to the semiconductor light emitting device, an area of a first surface of the wavelength converting element facing the semiconductor light emitting device being greater or similar to an area of a first surface of the semiconductor light emitting device, the substantially flat wavelength converting element comprising a wavelength converting layer, and the area of the first surface of the wavelength converting element being substantially the same as the area of a first surface of the die; and
a reflective material in direct contact with a side of the semiconductor light emitting device and a portion of the first surface of the wavelength converting element extending beyond the first surface of the semiconductor light emitting device.
2 . The lighting structure of claim 1 wherein the area of the first surface of the substantially flat wavelength converting element is no more than 150% of an area of a first surface of the semiconductor light emitting device.
3 . The lighting structure of claim 1 wherein the wavelength converting element further comprises a transparent layer, the wavelength converting layer is deposited on the transparent layer, the transparent layer comprising glass and the wavelength converting layer comprising phosphor mixed with a transparent material and laminated on the glass.
4 . The lighting structure of claim 1 wherein a length that the wavelength converting element extends beyond an edge of the semiconductor light emitting device is no more than 30 μm.
5 . The lighting structure of claim 1 , wherein the die is one of a plurality of wafer die on a semiconductor light emitting device wafer.
6 . The lighting structure of claim 5 , wherein the semiconductor light emitting device wafer is sigulated to separate the die from the plurality of wafer die.
7 . The lighting structure of claim 1 , wherein the reflective material comprises TiO 2 .
8 . The lighting structure of claim 7 , wherein the TiO 2 is deposited in a silicone material.
9 . A method comprising:
forming a wavelength converting element comprising a wavelength converting layer;
after said forming, attaching the wavelength converting element to a wafer of semiconductor light emitting devices;
after said attaching, dicing the wavelength converting element and the wafer of semiconductor light emitting devices to form a plurality of lighting elements;
after said dicing, disposing the plurality of lighting elements on a handling substrate; and
disposing a reflective material between the plurality of lighting elements.
10 . The method of claim 9 wherein forming a wavelength converting element comprises laminating a wavelength converting layer on a glass layer.
11 . The method of claim 9 , further comprising depositing the wavelength converting layer on a transparent layer.
12 . The method of claim 11 , further comprising removing the transparent layer after said attaching.
13 . A method comprising:
forming a wavelength converting element comprising a wavelength converting layer, the wavelength converting element being rigid;
after said forming, attaching the wavelength converting element to a plurality of diced semiconductor light emitting devices disposed on a first handling substrate;
after said attaching, dicing the wavelength converting element to form a plurality of lighting elements,
after said dicing, disposing the plurality of lighting elements on a second handling substrate; and
disposing a reflective material between the plurality of lighting elements.
14 . The method of claim 13 wherein the wavelength converting layer is disposed on a transparent layer.
15 . The method of claim 14 wherein forming the wavelength converting element comprises laminating the wavelength converting layer on the transparent layer.
16 . The method of claim 14 further comprising removing the transparent layer after said dicing.
17 . The method of claim 16 wherein:
the wavelength converting element comprises a thermal release layer disposed between the wavelength converting layer and the transparent layer; and
removing the transparent layer comprises removing by thermal release.