We have been developing a combined technique of using ultra-fast laser in conjunction with fiber-probe delivery to ablate substrate surface in near-field region. Often it is found too difficult to do an in-situ nanometer machining on a pre-formed nanometer structure using traditional optical microscope due to resolution limited by fundamental diffraction limit. Therefore a processing method with nanometer metrology that can be applied in air is advantageous for precision machining on pre-formed nanometer structures. Fundamentally, diffraction limit also restricts the laser spot size to larger than half of the wavelength in free space optics. We will illustrate our technique of sub-diffraction limit drilling by using NSOM (near-field scanning optical microscope) delivered femto-second pulses with nanometer precision. Nanometer-scale surface topology modification has been demonstrated. The ablation characteristics are studied. A precision process control is also developed to reduce the influence of recoil force and debris buildup.

1.
Smolyaninov
,
I. I.
,
Davis
,
C. C.
, (
2001
)
Michromachining of Diamond with a Near-Field Scanning Optical Microscope
,
Optics Letters
,
26
,
19
,
1495
1497
.
2.
Huang
,
D. J.
,
Chimmalgi
,
A.
,
Grigoropoulos
,
C. P.
, (
2004
)
Nanostructure Fabrication Using Pulsed Lasers Combined with Scanning Probes
, in
Proceeding of 23th ICALEO
,
USA
, M104.
3.
Li
,
M.
,
Liu
,
X.
, (
2001
)
Femtosecond Laser Micromachining of Si-on-SiO2 for Photonic Bandgap Crystal Fabrication
,
JJAP
,
40
,
3476
.
4.
Li
,
M.
,
Ishizuka
,
M.
,
Liu
,
X.
,
Sugimoto
,
Y.
,
Ikeda
N.
,
Asakawa
,
K.
, (
2002
)
Nanostructuring in Submicron-level Waveguides with Femtosecond Laser Pulses
,
Optics Communications
,
212
/
1-3
,
159
163
.
5.
Li
,
M.
,
Mori
,
K.
,
Ishizuka
,
M.
,
Liu
,
X.
,
Sugimoto
,
Y.
,
Ikeda
,
N.
,
Asakawa
,
K.
, (
2003
)
A photonic bandpass filter for 1550 nm fabricated by femtosecond direct laser ablation
,
Applied Physics Letters
,
83
,
216
.
6.
Jia
,
J.
,
Li
,
M.
,
Thompson
,
C. V.
, (
2004
)
Amorphization of Silicon by Femtosecond Laser Pulses
,
Applied Physics Letters
,
84
,
3205
.
7.
Ohtsu
M.
et al, (
2003
)
Progress in Nano-Electro-Optics
,
1
19
.
8.
Lu
,
L. F.
, (
2004
)
Laser Nanomachining and Nanoprocessing-Frontiers beyond the Optical Diffraction Limit
, in
Proceeding of 23th ICALEO
,
San Francisco, USA
, M101.
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