MARK POSITION MEASURING METHOD EMPLOYING ELECTRON BEAM

• Main Authors: TAKIGAWA TADAHIRO, KATOU YOSHIHIDE
• Format: Patent
• Language: English
• Published: 07.12.1983
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

PURPOSE:To prevent any lowering or accuracy in alignment with the progress of the processing step even if an oxide film or the like is formed on a mark, by setting the grun range of the electron beam within the mark so that the depth or height of the mark and the grun range are in a specific relation to each other. CONSTITUTION:In a mark position measuring method employing an electron beam wherein an electron beam is applied to an alignment mark formed on a sample, and reflected electrons are detected to measure the mark position, the grun range RG of the electron beam within the mark is set to be such a value that h/RG<1/6 is established, where (h) represents the depth or height of the mark. As will be clear from the Figure, in which white and black circles represent alignment accuracies before and after the processing step, respectively, the deterioration of the mark signal with the progress of the processing step is made extremely small by setting the grun range RG so that the relation h/RG< 1/6 is established.