Untitled in english

Author(s)

Jorge Seki

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Escola Politécnica (EP/BC)
• Defense date: 1996-02-27

Examining board members

Megumi Saito; Luiz Carlos Kretly; Luiz Carlos Molina Torres

• Advisor: Megumi Saito

Abstract

This work is based on the study of the optical Pattern Generator Research Devices Instruments (RDI) MICROPATTERN PRINTER model IMAGEEM 100 installed at the EPUSP Microeletronic Laboratory (LME) for the development of a confection technique of low complexity photomasks/reticles with resolutions of about two microns, improving a lot the photolitographic system traditionally used in the laboratory. After we had the Pattern Generator installed and worked with it for a while. (Project GEPA Pattern Generator), we had faced two difficulties: the criterion for the definition of the process parameters related to the photoresist exposed at the Pattern Generator, and, because of several possibilities offered by the equipment, the definition of the correct exposure parameters. The dimensions we have proposed in our activities with the equipment have made the photolitographic process critical and non-standard regarding the usual patterns of the laboratory. We faced problems due to a lack, not only of the explanation about some stages of the photolitographic process, but also of the understanding about the exposure optical system of the equipment. This work came out as a resulto f these difficulties. Firstly, it as conducted the detailed revision on the photolitographic subject, in relation to the previous study (theoretical and practical) of the characteristics of the photoresist, as well as in relation to the exposure optical system.Thus, it was possible to define a criterion for the acquisition of the parameters of the optimized process from the photoresist. The maximum resolutions of any objective lenses of the equipment were characterized with the process parameter obtained using this criterion. In order to implemente this work also as an equipment hadbook (in addition to the one offered by the manufacturer which is insuficiente), some useful information were put together for the preparation of layouts with the system and information about the Pattern Generators operation to the creation of photomasks/reticles of the same edited layout. We verified that the maximum resolution of two microns promised by the manufacturer is obtained with degraded contrast. We also tested the functionality of the encoder at the correct positioning of the XY stage and, from this, we have concluded that the main use of the equipment is for manufacturing reticles, and the execution of the final photomask is limited to its low complexity. In order to have a guindance about the capability of the equipment, some examples of phots/reticles previously done with the system are presented in the work. (AU)