A chip is provided which includes an active semiconductor region and a
field effect transistor ("FET") having a channel region, a source region
and a drain region all disposed within the active semiconductor region.
The FET has a longitudinal direction in a direction of a length of the
channel region, and a transverse direction in a direction of a width of
the channel region. A first dielectric stressor element having a
horizontally extending upper surface extends below a portion of the
active semiconductor region, such as a northwest portion of the active
semiconductor region. A second dielectric stressor element having a
horizontally extending upper surface extends below a second portion of
the active semiconductor region, such as a southeast portion of the
active semiconductor region. Each of the first and second dielectric
stressor elements shares an edge with the active semiconductor region,
the edges extending in directions away from the upper surface.