Abstract: A wavy FET structure includes a semiconductor substrate having a first conductive type, a source doped region and a drain doped region both having a second conductive type, a gate structure, and first and second metal layers. The semiconductor substrate includes a surface and a fin portion formed on the surface. The fin portion has first and second ends along its length direction. The source doped region is formed on the first end and on a first partial region at a lower portion of the first end and contacting the surface. The drain doped region is formed on the second end and on a second partial region at a lower portion of the second end and contacting the surface. The gate structure covers the fin portion. The first metal layer contacts and covers the source doped region. The second metal layer contacts and covers the drain doped region.