TY - JOUR
T1 - Angular and energy distribution of Sn ion debris ejected from a laser-produced plasma source, for laser power densities in the range suitable for extreme ultraviolet lithography
AU - O'Connor, A.
AU - Morris, O.
AU - Sokell, E.
PY - 2011/4/1
Y1 - 2011/4/1
N2 - In this paper, experimental results are presented for the spatial and energy distributions of charge-discriminated Sn ions ejected from laser-produced plasmas. The plasmas were formed on solid, planar Sn targets, irradiated with a Nd:YAG laser. Ions were investigated using a calibrated electrostatic sector analyzer, scanning an energy-to-charge ratio range of 0.22 to 2.2 keV / e for emission angles between 20 and 80 degrees relative to target normal. Results were obtained for three laser power densities, in the region suitable for inducing significant extreme ultraviolet emission, of the order 1.5-8.1 × 10 × 11 W/ cm2. The fully differentiated data were found to be well characterized by Gaussian fits, which allowed trends in the emission profiles to be readily quantified. Ions of set energy and charge were observed to possess a preferential angle of emission, the superposition of which yields a physical basis for the total angular emission observed previously and in this work. The experimental results obtained have been related to physical processes within the plasma that influence the energy and angle of ejection of ions from laser produced plasmas.
AB - In this paper, experimental results are presented for the spatial and energy distributions of charge-discriminated Sn ions ejected from laser-produced plasmas. The plasmas were formed on solid, planar Sn targets, irradiated with a Nd:YAG laser. Ions were investigated using a calibrated electrostatic sector analyzer, scanning an energy-to-charge ratio range of 0.22 to 2.2 keV / e for emission angles between 20 and 80 degrees relative to target normal. Results were obtained for three laser power densities, in the region suitable for inducing significant extreme ultraviolet emission, of the order 1.5-8.1 × 10 × 11 W/ cm2. The fully differentiated data were found to be well characterized by Gaussian fits, which allowed trends in the emission profiles to be readily quantified. Ions of set energy and charge were observed to possess a preferential angle of emission, the superposition of which yields a physical basis for the total angular emission observed previously and in this work. The experimental results obtained have been related to physical processes within the plasma that influence the energy and angle of ejection of ions from laser produced plasmas.
UR - http://www.scopus.com/inward/record.url?scp=79955368136&partnerID=8YFLogxK
U2 - 10.1063/1.3558988
DO - 10.1063/1.3558988
M3 - Article
AN - SCOPUS:79955368136
SN - 0021-8979
VL - 109
JO - Journal of Applied Physics
JF - Journal of Applied Physics
IS - 7
M1 - 073301
ER -