Title :
Long-pulse plasma immersion ion implantation using a grounded conduction grid
Author :
Zeng, Xuchu ; Kowk, Dixon T K ; Tian, Xiubo ; Chan, Chung ; Chu, Paul K.
Author_Institution :
Dept. of Phys. & Mater. Sci., City Univ. of Hong Kong, China
Abstract :
Summary form only given, as follows. The use of a grounded conducting grid positioned between the plasma source and sample chuck has been shown theoretically to allow direct current (DC) plasma immersion ion implantation (PIII). In addition to retaining the large area and parallel processing advantages of PIII, the implantation energy monotonicity and dose uniformity can be improved. We investigate the PIII process with the conducting grid in the long pulse mode, as pure DC PIII has some limitations and is not required in many applications. We experimentally measure the sheath expansion process and plasma stabilization time and determine the optimal instrumental parameters in this mode of operation. For example, our data show that the following conditions: H/sub 2/ pressure=5/spl times/10/sup -4/ Torr, RF power=1 kW, pulse width=500 /spl mu/s, and frequency=1 kHz can yield good results. We also measure the impact energy and dose distributions, and observe that the power and time efficiency can be substantially improved using long-pulse PIII compared to conventional short-pulse PIII. Our experimental results further indicate that DC plasma implantation is very hopeful.
Keywords :
ion implantation; plasma diagnostics; plasma instability; plasma materials processing; plasma sheaths; 1 kHz; 1 kW; 500 mus; 5E-4 torr; DC plasma implantation; H/sub 2/; H/sub 2/ pressure; RF power; conducting grid; direct current plasma immersion ion implantation; dose distributions; dose uniformity; frequency; grounded conducting grid; grounded conduction grid; impact energy; implantation energy monotonicity; large area parallel processing advantages; long pulse mode; long-pulse plasma immersion ion implantation; operation mode; optimal instrumental parameter; plasma source; plasma stabilization time; power efficiency; pulse width; sample chuck; sheath expansion process; time efficiency; Instruments; Parallel processing; Plasma applications; Plasma immersion ion implantation; Plasma materials processing; Plasma measurements; Plasma sheaths; Plasma sources; Radio frequency; Time measurement;
Conference_Titel :
Plasma Science, 2000. ICOPS 2000. IEEE Conference Record - Abstracts. The 27th IEEE International Conference on
Conference_Location :
New Orleans, LA, USA
Print_ISBN :
0-7803-5982-8
DOI :
10.1109/PLASMA.2000.855023