Mobile phones, personal digital assistants (“PDAs”), digital cameras, MP3 players, and other electronic devices utilize light-emitting diodes (“LEDs”), organic light-emitting diodes (“OLEDs”), polymer light-emitting diodes (“PLEDs”), and other solid-state transducer devices for backlighting. Solid-state transducer devices are also used for signage, indoor lighting, outdoor lighting, and other types of general illumination. FIG. 1 shows a cross-sectional view of a conventional LED device 10 with vertical contacts. The LED device 10 includes a support substrate 20 carrying an LED structure 12 that has an active region 14 (e.g., containing gallium nitride/indium gallium nitride (GaN/InGaN) multiple quantum wells (“MQWs”)) positioned between N-type gallium nitride (“N-GaN”) 16 and P-type gallium nitride (“P-GaN”) 18. The LED device 10 also includes a first contact 22 on the P-type GaN 18 and a second contact 24 opposite the first contact 22 on the N-type GaN 16. As further shown in FIG. 1, the LED device 10 can also include a converter material 26 and an encapsulant 28 positioned over one another on the LED structure 12. In operation, the LED structure 12 can emit a first emission (e.g., blue light) that stimulates the converter material 26 (e.g., phosphor) to emit a second emission (e.g., yellow light). The combination of the first and second emissions can generate a desired color of light (e.g., white light).
The LED structure 12 can be formed on a semiconductor wafer that includes several individual LED die. During conventional manufacturing processes, the wafers are cut into separate the LED die, and then the individual LED die are packaged and tested. For example, the LED structure 12 can be diced from a wafer-level LED structure and attached to the support substrate 20. The converter material 26 and the encapsulant 28 can then be formed over the front of the singulated LED structure 12.
A challenge associated with such conventional LED packaging is that forming the converter material 26 and the encapsulant 28 on singulated die requires precise handling that increases manufacture time and leads to increased packaging costs. Another concern is that mounting each LED die to a separate support substrate is also time consuming and requires more precise handling. Additionally, LED devices generally produce a significant amount of heat, and the different coefficients of thermal expansion between the LED structure and the underlying support substrate can result in delamination between the two or other damage to the packaged device.