An energy-efficient method and system for processing target material such
as microstructures in a microscopic region without causing undesirable
changes in electrical and/or physical characteristics of material
surrounding the target material is provided. The system includes a
controller for generating a processing control signal and a signal
generator for generating a modulated drive waveform based on the
processing control signal. The waveform has a sub-nanosecond rise time.
The system also includes a gain-switched, pulsed semiconductor seed laser
for generating a laser pulse train at a repetition rate. The drive
waveform pumps the laser so that each pulse of the pulse train has a
predetermined shape. Further, the system includes a laser amplifier for
optically amplifying the pulse train to obtain an amplified pulse train
without significantly changing the predetermined shape of the pulses. The
amplified pulses have little distortion and have substantially the same
relative temporal power distribution as the original pulse train from the
laser. Each of the amplified pulses has a substantially square temporal
power density distribution, a sharp rise time, a pulse duration and a
fall time. The system further includes a beam delivery and focusing
subsystem for delivering and focusing at least a portion of the amplified
pulse train onto the target material. The rise time (less than about 1
ns) is fast enough to efficiently couple laser energy to the target
material, the pulse duration (typically 2-10 ns) is sufficient to process
the target material, and the fall time (a few ns) is rapid enough to
prevent the undesirable changes to the material surrounding the target
material.