TY - JOUR
T1 - Electron holographic characterization of nanoscale charge distributions for ultra shallow PN junctions in Si
AU - Chakraborty, P. S.
AU - McCartney, Martha
AU - Li, J.
AU - Gopalan, C.
AU - Singisetti, U.
AU - Goodnick, Stephen
AU - Thornton, Trevor
AU - Kozicki, Michael
N1 - Funding Information:
This work was supported by the Office of Naval Research MURI program and by Semiconductor Research Corporation under the grant SRC#942.001. The authors would like to thank the Center for High Resolution Electron Microscopy and K. Franzreb of the SIMS facility at Arizona State University for assistance.
PY - 2003/7
Y1 - 2003/7
N2 - This study extends electron holography as a quantitative characterization tool for nanoscale charge distributions associated with ultra shallow PN junctions in Si, which are needed for fabricating nanoscale MOSFETs, Si quantum dots and single electron transistors. The ultra shallow junctions were fabricated using rapid thermal diffusion from a heavily doped n-type surface source onto a heavily doped p-type substrate. Chemical characterization of the dopant profiles was performed using secondary ion mass spectrometry, which were analyzed to derive the metallurgical junction depth. 1-D characterization of the electrical junction depth associated with the electrically activated fraction of the incorporated dopants was performed using off-axis electron holography in a transmission electron microscope. 1-D potential profiles across the p-n junctions derived from electron holographic analysis were used to calculate the electric field and total charge distributions in the space charge region of the p-n junctions using numerical derivatives. Quantitative comparison between calculated electric field and total charge from the measured potential profiles and the simulated distributions using the secondary ion mass spectrometry profiles provide a reasonable estimate of the electrical activation of dopants in the ultra shallow junctions considered for this investigation.
AB - This study extends electron holography as a quantitative characterization tool for nanoscale charge distributions associated with ultra shallow PN junctions in Si, which are needed for fabricating nanoscale MOSFETs, Si quantum dots and single electron transistors. The ultra shallow junctions were fabricated using rapid thermal diffusion from a heavily doped n-type surface source onto a heavily doped p-type substrate. Chemical characterization of the dopant profiles was performed using secondary ion mass spectrometry, which were analyzed to derive the metallurgical junction depth. 1-D characterization of the electrical junction depth associated with the electrically activated fraction of the incorporated dopants was performed using off-axis electron holography in a transmission electron microscope. 1-D potential profiles across the p-n junctions derived from electron holographic analysis were used to calculate the electric field and total charge distributions in the space charge region of the p-n junctions using numerical derivatives. Quantitative comparison between calculated electric field and total charge from the measured potential profiles and the simulated distributions using the secondary ion mass spectrometry profiles provide a reasonable estimate of the electrical activation of dopants in the ultra shallow junctions considered for this investigation.
KW - Dopant activation
KW - Electron holography
KW - Rapid thermal diffusion
KW - Space charge region
KW - Ultra shallow junctions
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U2 - 10.1016/S1386-9477(03)00302-3
DO - 10.1016/S1386-9477(03)00302-3
M3 - Conference article
AN - SCOPUS:0043011385
SN - 1386-9477
VL - 19
SP - 167
EP - 172
JO - Physica E: Low-Dimensional Systems and Nanostructures
JF - Physica E: Low-Dimensional Systems and Nanostructures
IS - 1-2
T2 - Fourth International Symposium on Nanostructures and Mesoscopi
Y2 - 17 February 2003 through 21 February 2003
ER -