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Showing papers on "Electron-beam lithography published in 1972"


Journal ArticleDOI
TL;DR: In this article, a computer-controlled scanning electron microscope (CCSEM) was used to expose polymethyl methacrylate (PMM) in a resist form for microelectronic device fabrication and in bulk form to determine energy dissipation profiles.
Abstract: In modern microelectronics, complicated structures with very small dimensions must be fabricated on active-device materials. This task has been traditionally accomplished by photolithographic techniques, but electron-beam exposure of resist materials has recently been explored [1]-[3]. Submicron electron devices have been fabricated in several laboratories, often featuring a flying-spot scanner to generate the pattern being exposed [4]-[7]. Paper tape drives have been used for repetitive patterns [8], and computer control of the electron beam has been reported also [1], [9]. The electron resist that has shown the highest resolution to date appears to be poly-(methyl methacrylate) (PMM). We have used this material in a resist form for microelectronic device fabrication, and in bulk form to determine energy dissipation profiles. The exposure is performed with a computer-controlled scanning electron microscope (CCSEM). In this paper, we describe the electron beam system briefly, discuss the processes involved in resist exposure and development, describe our exposure procedures using the CCSEM, and show results of fabricated devices and energy dissipation studies.

33 citations


Patent
13 Sep 1972
TL;DR: In this paper, a retarding electrode is added to the beam of the primary electron to remove the undesirable stray electrons from the primary electrons on the basis of the energy difference between the two groups of electrons.
Abstract: In scanning electron microscopes, the beam of primary electrons generated by an electron gun contains low energy stray electrons as it passes through the condenser lens system on route to the specimen. The stray electrons adversely affect the secondary electron image. By incorporating a retarding electrode maintained at negative potential as described in this specification, the undesirable stray electrons are removed from the beam of primary electrons on the basis of the energy difference between the two groups of electrons.

9 citations


Journal ArticleDOI
TL;DR: In this paper, it was shown that the cross-linking of a negative photoresist under the influence of an electron beam occurs by free-radical polymerisation. But this was not the case for positive photoresists.
Abstract: The literature dealing with the decomposition of positive and negative photoresists by actinic light and by electron bombardment is reviewed, and the action of a stream of electrons on other organic materials, metals, and inorganic dielectrics is discussed. A mechanism producing internal irradiation of the resist is considered: the incident electrons excite the resist molecules into fluorescence and phosphorescence. The influence of the (metallic or dielectric) substrate on the achievement of the required line widths is discussed. It is shown that the cross-linking of a negative photoresist under the influence of an electron beam occurs by free-radical polymerisation. 65 references.

2 citations