Carbon Nanotube (CNT) is an excellent field emission source, and is widely explored in applications like sensors, AFM probes, cathodes for Carbon Nanotube Field Emission Display (CNT-FED), and cathodes for microwave device. The requirements on field emission characteristics for these applications vary, but it is often necessary to attach CNT onto a metal electrode surface. When CNT is grown directly on a metal surface by conventional CVD processes, the poor adhesion of CNT to the metal surface and, in some cases, low electrical conductivity leave room for improvements. We hot-bond CVD grown CNT with Ball Grid Array (BGA) of 0.5 mm diameter Tin alloy (Sn63/Pb37) spheres placed in pre-designated positions on a metal surface to form a cold cathode for microwave device applications. The forming temperature is about 200°C. This method not only provides an easy way to make CNT-metal cathode, it also greatly improve the field emission characteristics of the original CNT. The turn on electric field (at J= 1μA/cm2) is 1.56 V/μm with the field enhancement factor β reaching 2203. The ΔJ/ΔE is around 1.09M.