利用晶圓接合與電鍍技術製作高功率氮化鎵族發光二極體

Abstract

本研究是先在矽基材上製作規則的凹槽陣列，接著將銅電鍍到這規則的陣列上，再將發光二極體的結構接合到此矽基材上。主要是因為利用銅基材去取代藍寶石基板使其具有較高的散熱性，可以使元件在較高的飽和電流下驅動以達到高功率的目標，然而，銅金屬是延展性佳的材料，因此，在整個元件的製做過程中，易造成發光二極體元件毀壞（尤其是在切割晶粒時），利用本實驗的方法可以提升製造高功率發光二極體之良率。 在實驗中我們分為基板的製作、晶圓接合、雷射剝離及元件製作四個部份來討論，利用改變製程的步驟來完成我們所想要的元件。利用光學顯微鏡(OM)、掃描式電子顯微鏡(SEM)及原子力顯微鏡(AFM)對接合界面作分析，接著量測模擬元件的電性去討論製程上需要改進的地方。

In this thesis, Cu film was electroplated on the Si wafer that has regular surface patterns, and then bonded with the LED structure. The bonded LED device on Cu substrate could be operated in a much higher injection forward current. The significant improvement might be caused by the Cu substrate which has higher thermal conductivity than conventional Sapphire substrate. However, Cu substrate is a ductile metal plate and easy to deform during the processing. The deformation of the Cu substrate will destroy the LEDs that were bonded on the Cu substrate. Finally, LEDs will be fabricated on the patterned Cu/Si substrate to make high-power LEDs and solve the deformation problem in processing. We have four major issues of formation of substrate, wafer bonding, laser lift-off and device fabrication. We change experimental conditions and process for the target which high-power LEDs. Analysis of the bonding interface by optical microscopy (OM), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Finally, we will discussion what it can be improved by simulation device’s electric properties.