AVS 58th Annual International Symposium and Exhibition
    Nanomanufacturing Science and Technology Focus Topic Tuesday Sessions
       Session NM+NS+MS-TuA

Paper NM+NS+MS-TuA11
Laser-Assisted Electron-Beam Induced Deposition and Etching

Tuesday, November 1, 2011, 5:20 pm, Room 207

Session: Manufacturable Nanoscale Devices and Processes
Presenter: Nick Roberts, University of Tennessee and Omniprobe, Inc.
Authors: N.A. Roberts, University of Tennessee and Omniprobe, Inc.
J.D. Fowlkes, Oak Ridge National Laboratory
P.D. Rack, University of Tennessee and Oak Ridge National Laboratory
G.A. Magel, Omniprobe, Inc.
H.M. Marchman, Omniprobe, Inc.
C.D. Hartfield, Omniprobe, Inc.
T.M. Moore, Omniprobe, Inc.
Correspondent: Click to Email

Focused electron-beam induced deposition (EBID) and etching (EBIE) are direct-write nanofabrication techniques that allow localized deposition or etching of materials without the need for resists. These deposition and etching processes are controlled by electron-beam dissociation of a precursor gas. In both cases, by-product species are created, and if the unwanted byproduct is not desorbed from the surface it will be incorporated into the deposit or reduce the etch rate for deposition and etching, respectively. Substrate heating has been used in experiments to enhance desorption by reducing the residence time of the by-product. The substrate heating has the same impact on the residence time of the precursor gas and therefore reduces the growth or etch rate of the process. Ex situ treatments of deposits have also been investigated to remove impurities with some success, but these treatments results in void formation and shape changes. In situ laser processing at short pulse widths is ideal for electron-beam induced processing because desorption of the by-products can be achieved by local heating of the sample, but the narrow pulse width results in a short heating time and cooling time. Thus the by-products can be effectively desorbed and adequate recovery time for fresh reactant to re-adsorb.

Laser-assisted EBID and EBIE processes are made possible through the use of the OptoProbe™, which is an optical imaging and processing system that can be attached to an SEM and used in conjunction with an appropriate gas injection system. The design of this port-mounted optical accessory enables simultaneous optical imaging and delivery of laser irradiation to a sample within the SEM, without interfering with normal SEM/FIB imaging and processing modes. The optical system is mounted on a 3-dimensional nanomanipulator so that precision alignment and focusing is easily achieved. For this work, the OptoProbe™ has been optimized to deliver a high-irradiance near-infrared laser spot to provide localized time-dependent sample heating for enhancing focused electron-beam induced deposition and etching. In this presentation, we will discuss recent experimental results as well as modeling of laser-assisted EBID of Au and EBIE of SiOx using XeF2.