Using a <670> zone axis for convergent beam electron diffraction measurements of lattice strain in strained silicon.
Convergent beam electron diffraction patterns of silicon from the gate channel region of a complementary metal-oxide-semiconductor transistor with recessed Si(.82)Ge(.18) stressors were analysed using three zone axes: <230>, <340> and <670>. Values measured using these axes were compared with each other with regards to strain along the [110] and the [001] directions. It was demonstrated that strain measurements made using all three axes showed reasonable agreement with each other: an increase in the [110] compressive strain and a switch from compressive to tensile strain in the [001] with decreasing distance below the gate. It was also observed that the strain calculations using the <230> axis had the lowest uncertainty whereas the <670> axis allowed for measurements closest to the gate due to the improved lateral resolution at that tilt angle.
Diercks
D R
DR
Center for Advanced Research and Technology (CART), University of North Texas, Denton, TX 76207, USA. david.diercks@unt.edu
Kaufman
M J
MJ
Irwin
R B
RB
Jain
A
A
Robertson
L
L
Weijtmans
J W
JW
Wise
R
R