A method of manufacturing a transistor and a structure thereof, wherein a
very shallow region having a high dopant concentration of germanium is
implanted into a channel region of a transistor at a low energy level,
forming an amorphous germanium implantation region in a top surface of
the workpiece, and forming a crystalline germanium implantation region
beneath the amorphous germanium implantation region. The workpiece is
annealed using a low-temperature anneal to convert the amorphous
germanium region to a crystalline state while preventing a substantial
amount of diffusion of germanium further into the workpiece, also
removing damage to the workpiece caused by the implantation process. The
resulting structure includes a crystalline germanium implantation region
at the top surface of a channel, comprising a depth below the top surface
of the workpiece of about 120 .ANG. or less. The transistor has increased
mobility and a reduced effective oxide thickness (EOT).