Carbon Nanotubes are being studied for their special 1D properties. In this work, an attempt is made to study the factors behind carbon nanotube growth. Growth is carried out by thermal Chemical Vapor Deposition (CVD) using a solid catalyst. Single Electron Transistors (SETs) made from carbon nanotubes are studied. Measurements are carried out on metallic and semiconducting nanotubes at room temperature, 77 K and 4 K.