Electron beam writing

Preliminary experiments with electron-beam writing and ion-beam projection lithography have demonstrated that the S-layer may also be patterned by these techniques in the sub-lOO-nm range (nnpnblished resnlts). The combination of ion-beam projection lithography and S-layers as resist might become important in the near fntnre, since ion beams allow the transfer of smaller featnres into S-layer lattices compared to optical lithography. 

Figure 13. Outline of the pattern generation for integrated circuits provided by electron beam writing on chemically suitable polymer films, which are thus sensitized for development.

We attempted to use this increase in refractive index in fabricating polyimide optical waveguides. The fabrication of a fluorinated polyimide waveguide by the direct electron beam writing method is described in Section 4.3.2. We also investigated the changes in the refractive index of fluorinated polyimide films by synchrotron radiation. 7 The refractive index at a wavelength of 589.6 nm increased by 1.3% and the thickness decreased by 0.69% for fluorinated polyimide film after 30 min of synchrotron irradiation. From the XPS data the synchrotron radiation leads to production of a fluorine-poor surface. 

The refractive index of fluorinated polyimide can be controlled precisely by adjusting the election beam irradiation dose as described in Section 3.2.2, and this feature can be exploited in fabricating polyimide optical waveguides. This section describes fluorinated polyimide waveguides fabricated by the direct electron beam writing method. ... 

The current technological competition for practical fabrication of 0.5 - 1.0 pm feature is in between photolithography and electron beam direct writing, and between single layer and multi-level resist. For less than 0.5 pm, the use of electron beam writing with multilevel resist will be inevitable. Further developments in electron resists from the standpoint of both resist chemistry and process development will be necessary to establish the electron beam lithography. 

Assembled particles can also be directly removed by electron-beam writing. This was demonstrated for PMMA particles. Stripes with a width of about... 

Another application concerns the fabrication of metallic and bimetallic nanostructures on surfaces by electron beam induced metallization of the RjN Br"-stabilized Pd and Pd/Pt colloids [48]. In a simple three-step process, namely dip-coating, electron beam writing of patterns (e.g. lines) and rinsing, lines having a thickness of only 30 nm were achieved. This technique is of potential interest in lithography and catalysis. Finally, tetraalkylammonium salt-stabilized transition... 

Griffith S, Mondol M, Kong DS, Jacobson JM. Nanostructure fabrication by direct electron beam writing of nanoparticles. J. Vac. Sci. Technol. B 2002 20 2768-2772. 

Buried channel-fluorinated waveguides consisting of a single material can be fabricated by direct electron beam writing, and we hope to develop novel optical devices by using this method. 

The nanoimprint was first developed by Chou and colleagues.Their process is called thermal nanoimprint, which is shown in Figure 4.1. The transfer layer on a Si wafer is thermal plasticity polymethylmethacrylate (PMMA) (Tg = 105°C). A mold of Si02 is produced by electron beam writing. 

Many additional fabrication methods are described in the references. Electron-beam writing is a high-resolution... 

Templates for assembly were cast in PDMS using nanostructmed silicon masters. See Supplementary Information, for details of the electron-beam writing and the processing of these masters. The masters were used to cast large numbers of silicone templates. The PDMS used is a variation of the commercially available product. It has a higher elastic modulus and can be patterned at higher fidelity. All templates were fabricated on backplanes cut from display glass (175 xm, Schott AG). 

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