Laser-Scanning Probe Microscope Based Nanoprocessing of Electronics Materials

Abstract

Recently, scanning probe microscope (SPM) has become a promising technique for nanofabrication. In this paper, we present a novel method of nano-fabrication, namely, nano-fabrication by atomic force microscope (AFM) tips under laser irradiation. The SPM was operated as an AFM. During imaging and nano-fabrication, the AFM is in constant force mode. The tip is fixed with the sample moving via a tube scanner. Nano-lithography software controls the scanner motion in x and y directions. The SPM has an open architecture allowing an external laser beam incident on the tip at an incident angle between 0 to 45 • . A vertically-polarized Nd:YAG pulsed laser with a pulse duration of 7 ns was focused on the tip. An electrical shutter was introduced to switch the laser irradiation. Alignment between the laser beam and the tip was performed under a high-power charge coupled device (CCD) microscope. The kinetics of the nanostructure fabrication has been studied. Craters were created in air ambient under different laser pulse numbers, pulse energies and tip force. The feature size of the craters, which are in the nanometer scale, increases with the pulse number, pulse energy and the tip force. This technique has potential applications in nano-lithography and high-density data storage.

Laser precision engineering: from microfabrication to nanoprocessing

“…During the nanopatterning, the tip functions like an antenna and ultrafast laser irradiation results in an electric field enhancement of 150 times, which causes the thin-film materials to be removed under the SPM tip. Lu et al used a different laser source, 532-nm/7-ns Nd:YAG laser (which is much cheaper, more reliable and has a smaller footprint than the femtosecond laser) to fabricate the surface nanopatterns at a spatial resolution down to 10 nm as well [30]. Compared to ultrafast laser irradiation that has a minimum heat dose applied on the silicon tip, nanosecond light irradiation may cause a tip temperature rise and tip expansion.…”

Localized radiative energy transfer from a plasmonic bow-tie nano-antenna to a magnetic thin film stack

“…Once the scattered field is solved via the FEM, the total field can be obtained using Eq. (6). Conversion of the field quantities into power quantities is achieved by applying the Poyntings theorem [27,28] to the geometry given in Fig 1. The dissipated power within the sample due to the near-field electromagnetic radiation can be obtained by utilizing Poynting's theorem [27,28] …”

“…When objects are separated by less than a subwavelength scale, the radiative energy transfer between the surfaces can be several orders higher than predicted by Planck's blackbody radiation. The drastic improvement of the radiative energy transfer has potential applications in emerging technologies including heat-assisted magnetic recording [1,2,3], thermophotovoltaic energy devices [4,5], and optically-assisted nanomanufacturing [6,7].…”

Droplet-Assisted Laser Direct Nanoscale Writing on Silicon

“…Laser nanolithography uses a semiconductor, metallic nanoparticles, or a tip-based microscope to enhance the laser intensity directly beneath the particles or tips [6]; however, they have their own technical barriers. In tip-based near-field laser nanolithography, the tip is easily damaged [7], and the throughput is still low [8]. By applying micro/nanoscale spherical particles, the flexibility of the pattern design is limited and the particles are one-time use only.…”