Electron beam sensitivity

No, except to electron beam-sensitive materials and during depth profiling... 

Applications of CL to the analysis of electron beam-sensitive materials and to depth-resolved analysis of metal-semiconductor interfaces by using low electron-beam energies (on the order of 1 keV) will be extended to other materials and structures. 

Figure 42. A plot of proton beam vs electron beam sensitivity for several resist systems. COP is a copolymer of glycidyl methacrylate and ethyl acrylate, PVC is poly (vinylcinnamate), PCS is poly (chlorostyrene), PTBMA is polyO-butyl methacrylate), PVA is poly (vinyl acetate), PMMA is poly (methyl methacrylate). (Reproduced with permission from Ref. 57 J...

The electron beam sensitivities of a random sample of co- and terpolymers were also determined, and were found to be essentially equal to that of PMMA. The value of 5X10 C/cm was largely invariant with oxime ester concentration, and the presence of methacrylonitrile had no effect (12). 

Polyphosphinoboranes are of interest with respect to their potentially useful physical properties such as flame-retardant behaviour and an ability to function as precursors to BP-based ceramics. In addition, the electron-beam sensitivity of some polyphosphinoboranes has been demonstrated. This allows their use as lithographic resists for patterning applications when coated as thin films on substrates such as silicon (Figure 9.11). ... 

The conventional approach has been to take resists which were developed for electron lithography and apply them to x-ray lithography. To a first order, there is a strong correlation between the sensitivity of resist systems (positive or negative) to electron beam radiation and their corresponding sensitivity to x-ray radiation. Figure 11 shows a plot of the 20 kV electron beam sensitivity in... 

We have developed a new silicone based negative resist (SNR) by introducing the chloromethyl group into polydiphenylsiloxane. SNR has a high Tg (170 C), good electron beam sensitivity and excellent durability to 02 RIE (9). In this paper we describe the SNR preparation and characteristics, and demonstrate a high resolution of 2LR system using this resist. 

Several electron beam sensitivity curves are shown in Figure 2. From these sensitivity curves, we estimate the dose for starting point of gel formation (D0), dose required for 50% gel formation (Dos) an contrast (7-value) of SNR. 

Many halogen-substituted cresol/phenol-formaldehyde Novolak resins were prepared and tested for their electron beam sensitivity when mixed together with a photoactive compound. The following halogen-substituted phenols and cresols were used as starting materials o-, m-, p-chlorophenols o-,... 

For further enhancement of electron beam sensitivity, the chlorinated Novolak resin was studied using poly (2-methyl-1-pentene sulfone) as a dissolution inhibitor. The chlorinated Novolak resin mixed well with the polysulfone, and there was no phase separation observed when the films were spin-coated. With 13 wt% of the polysulfone, the chlorinated Novolak resist cast from a cellosolve acetate solution yielded fully developed images with R/Ra = 9.2 after exposure to 2 / 2. It gave fully developed images with R/R0 = 3.2 at a dose of 1 / 2, as shown in Figure 3. There are some problems with this resist system some cracking of the developed resist images... 

Vacuum Curing Effect. In the early stage of this work, we investigated a mixture of epoxy novolac and poly(p-vinyl phenol) (EP) to obtain an electron beam sensitive non-swelling resist. Epoxy novolac was chosen as the sensitizing component, because epoxy groups are known to be electron-beam-sensitive substituents (2). However, it is also known that electron beam resists... 

Electron-Beam Sensitivity of Cross-Linked Acrylate Resists... 

Although chain scissioning yields are only a secondary measure of sensitivity, the high G(s) values reported here for MMA-itaconlc acid copolymers have been supported by the good electron-beam sensitivities determined from a complete lithographic evaluation of these copolymers. A full discussion of these results Is beyond the scope of this paper but they have been reported elsewhere (15). 

However conventional positive electron beam resists like PMMA(4) or PBS(5.) do not have excellent dry etching resistance. The electron beam sensitivities of these positive resists primarily result from radiation-induced degradation of polymer main chains. If the main chain bonding force of these polymers is weakened in order to improve sensitivities, the dry etching resistances of these polymers will decrease. In such cases, sensitivity to electron beam exposure and dry etching resistance are in a trade-off relationship. 

---