PROJECT TITLE :
Additional Nitrogen Ion-Implantation Treatment in STI to Relax the Intrinsic Compressive Stress for n-MOSFETs
Based mostly on the strain extraction and measurement by the atomic-force-microscope–Raman technique with nanometer-level area resolution, the high compressive stress regarding 700 MPa on the Si crucial dimension (CD) is observed in the current complementary metal–oxide–semiconductor (CMOS) transistor. The difference of thermal expansion between Si and Shallow trench isolation (STI) oxide throughout the whole thermal budget for the standard CMOS transistor manufacture process leads to this high compressive stress in Si CD and can any degrade the electron carrier mobility regarding twenty five$p.c$ seriously. So as to relax this intrinsic-processed compressive stress in Si CD and recover this device performance loss, the novel method is proposed in this paper in addition to the usage of one-side pad-SiN layer demonstrated in our previous work. With this novel process of additional nitrogen-ion implantation (IMP) treatment in STI oxide, it will be found that the less compressive stress within the Si CD can be achieved by the smaller difference of thermal expansion coefficients between Si and highly n-doped $hboxSiO_2$ STI oxide. The formation of Si–N bonding within the STI-oxide region can be monitored by Fourier-rework infrared spectroscopy spectra, and the thermal expansion coefficients for Si, $hboxSiO_2$, and SiN are 2.half dozen, 0.four, and a pair of.87 ppm/K, respectively. The relaxation of intrinsic-processed compressive stress within the Si CD of concerning four hundred MPa by this proposed further nitrogen IMP treatment contributes $sim$14 $%$ electron-carrier-mobility enhancement/recovery. The experimental electrical knowledge agree well with the th- oretical k.p calculation for the strained-Si theory.
Did you like this research project?
To get this research project Guidelines, Training and Code... Click Here