Siemens Aktiengesellschaft

Kabushiki Kaisha Toshiba

Siemens Microelectronics Limited

Andreas Grassmann

Katsuhiko Hieda

Thomas Fischer

A shading film of chrome is formed entirely on one surface of a circular substrate of quartz. The substrate is rotated and resist is applied to the shading film. Since the substrate is shaped in a circle, the resist spreads uniformly on the entire surface of the shading film by the centrifugal force. Therefore, the resist has a substantially uniform film thickness over almost the entire surface of the shading film. This resist is patterned to form a resist pattern. By etching the shading film with the resist pattern used as a mask, a pattern preferable in accuracy of dimensions can be formed.

Mask blank and method of producing mask

A lithographic system with improved control of critical dimensions (CD). The lithographic system includes a detector for determining the amount of energy absorbed by the photoresist. This enables the lithographic system to expose each field with the required exposure dose, thus reducing variations in CD.

Control of critical dimensions through measurement of absorbed radiation

The photolithographic etching of contact holes in trenches in an insulator layer over a silicon body is improved by adjusting properly the depth of the trench and the thickness of the photoresist used in the photolithography.

Growing community of inventors

Bad Abbach, Germany

Andreas Grassmann