Dual Integrated Deflector And Drive Electronics for High-Speed Electron-Beam Blanking System
Original Publication Date: 1991-Jul-01
Included in the Prior Art Database: 2005-Apr-03
Lieberman, JE: AUTHOR [+1]
Disclosed is a beam blanking system for an E-beam lithography tool which provides large deflection range with no loss in blanking speed.
Dual Integrated Deflector And Drive Electronics for
a beam blanking system for an E-beam
lithography tool which provides large deflection range with no loss
in blanking speed.
In the Hontas
E-beam lithography tool, the shaped spots are
written on the product in a sequential fashion. The finite time
required for the blanking function to occur in-between written spots
is wasted or dead time and has a direct impact on the overall system
throughput. Faster blanking deflectors typically have reduced
deflection sensitivity which require higher voltage drive amplifiers.
High voltage amplifiers are inherently slower than low-voltage
amplifiers due to slow rate and current load capacities.
blanking system is developed by taking advantage
of a property of the Hontas tools. Beam blanking deflection
magnitude during the time period of writing one spot to the next does
not have to be as large as during longer time periods. During longer
time periods a large blanking deflection is required to minimize
leakage exposures on the product. By integrating both high-speed and
large-range deflectors in one unit, a very high-speed blanking system
is produced. The system consists of a low-voltage high-speed
deflector with drive electronics and a lower-speed high-voltage
deflector with drive electronics either on the same or opposite axis.
illustrates a deflection system utilizing one set of
deflectors for the high-voltage blanking and an additional set of
deflectors acting along the opposite axis for the high-speed
blanking. A plate type of deflector is chosen for the high-voltage
blanking because of good sensitivity and a rod-type of deflector for
the high- speed blanking due to low capacitance properties. This
system requires the drive electronics to provide equal and opposite
voltages for each set of deflectors. V for the high-voltage
deflector and v for the high-speed deflector.
Fig. 1(b) illustrate...