Method of fabricating semiconductor devices

Abstract

Vertical high power LEDs are the technological choice for the application of general lighting due to their advantages of high efficiency and capability of handling high power. However, the technologies of vertical LED fabrication reported so far involve the wafer-level metal substrate substitution which may cause large stress due to the mismatch between metal substrate and LED layer. Moreover, the metal substrate has to be diced to separate LED dies which may cause metal contamination and thus increase the leakage current. These factors will lower the yield of LED production and increase the cost as well. The present invention is to disclose a novel method for the fabrication of GaN vertical high power LEDs and/or a novel method for the fabrication of GaN vertical high power LEDs which is compatible to mass production conditions. The novelty of the invention is that the island metal plating is conducted with the help of pattern formation techniques. Due to the small area of the islands, the stress generated between LED layer and metal islands is much less significant. Furthermore, due to the island metal plating and through the application of temporary supporting carriers the LED dies will be separated at the end of the fabrication process automatically or simply by applying slight mechanical stress or stretching the adhesive tape. This advantage avoids the metal dicing step and reduces the possibility of metal contamination and leakage current generation. Therefore, high yield and low cost will be realized using this novel method in LED production.