Sensitivity electron resists

Haller, R. Feder, M. Hatzakis, and E. Spiller, Copolymers of methyl methacrylate and methacryhc acid and their metal salts as radiation sensitive resists, 7. Electrochem. Soc., 126,154 (1979) M. Hatzakis, PMMA copolymers as high sensitivity electron resists, J. Vac. Sci. Technol. 16,1984 (1979). 

Hatzakis, PMMA copolymers as high sensitivity electron resists, J. Vac. Sci. Technol. 16, 1984 (1979). 

Figure 2. A sensitivity diagram showing the exposure window for electron resists.

Figure 4. Typical response or sensitivity curve for a negative electron resist. The value of Dg is obtained from Figure 3 and usually occurs at 0.5 - 0.7 normalized thickness.

Figure 5. Typical sensitivity or response curve for a positive electron resist. Positive resist response may also be plotted using other conventions (see...

Combustion products can affect sensitive electronic equipment. For example, hydrogen chloride (HCI) is formed by the combustion of PVC cables. Corrosion due to combusted PVC cable can be a substantial problem. This may result in increased contact resistance of electronic components. Condensed acids may result in the formation of electrolytic cells on surfaces. Certain wire and cable insulation, particularly silicone rubber, can be degraded on exposure to HCI. A methodology for classifying contamination levels and ease of restoration is presented in the SFPE Handbook... 

A Sensitive Positive-Working Cross-Linked Methacrylate Electron Resist... 

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... 

As a general rule, the sensitivity of conventional electron beam resists is not sufficient for economic throughput in an x-ray lithographic system. This is particularly true of positive electron resists such as PMMA, the most widely used x-ray resist for experimental purposes, whose sensitivity of >500 mJ/cm2 is some 100 times too slow for practical application. Even PBS only shows a sensitivity of 94 mJ/cm2 to PdLa x-rays. Consequently, the major research effort has concentrated on negative resists because of their higher inherent sensitivity. 

Recently chloromethylated polystyrene (CMS), a highly sensitive, high resolution electron resist with excellent dry etching durability, was developed. Very recently reactive intermediates in irradiated polystyrene, which is a starting material of CMS, have been studied and the transient absorption spectra of excimer (2-4), triplet states (2,5), charge-transfer complexes, and radical cations (6) of polystyrene have been measured. The present paper describes the cross-linking mechanism of the high sensitivity CMS resist and compares it to that of polystyrene on the basis of data on reactive intermediates of polystyrene and CMS. 

The sensitive electronic circuitry of a power transistor at the junction is protested by its case, which is a rigid metal enclosure. Heat transfer characteristics of a power transistor are usually specified by the manufacturer in terms of the case-to-ambient thermal resistance, which accounts for both Ihe natural convection and radiation heat transfers. 

The branch point between the Aox and the cytochrome respiratory chain arises at the ubiquinone pool. These terminal oxidases can be identified by using respiratory inhibitors and are divided as different groups according to the sensitivities or resistances to the inhibitors. Alternative respiration is activated by stress stimuli factors that constrict the electron flow through the cytochrome pathway [137]. However, the roles and the compositions of these pathways are... 

High sensitivity resists Table II summarizes the properties of representative positive electron resists. The polymers are classified into four groups according to the chemical structure. Almost all positive electron resists operate by main chain scission of polymer, resulting in a molecular weight decrease in exposed areas. Resist patterns are produced by development in a suitable solvent in which degraded polymer dissolve much faster than unexposed polymer. The sensitivity is determined by the scission probability and the solubility rate ratio for the degraded polymers. 

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