(Ba,Sr)TiO3 Films and Process Integration for Dram Capacitor

Part of the Electronic Materials: Science and Technology book series (EMST, volume 3)


The memory capacity of the DRAM, a major application of LSI and the technology driving semiconductor devices, has quadrupled every three years. To increase device integration, we must solve not only the engineering problems, such as fine-patterning, microtransistor operation and wiring life, but also the problem of capacitor. The storage unit of a DRAM (cell) consists of a capacitor, which accumulates electric charge, and a switching transistor; accordingly, a certain amount of accumulated electric charge must be ensured to restrict device operation while the cell area is being reduced by miniaturization. To ensure accumulated electric charge sufficient for greater DRAM integration, capacitor dielectric film thickness has been reduced, electrode area has been increased by applying a three-dimensional structure, and capacitor materials have been changed to materials with high dielectric constants (from SiO2 films to so-called ON films obtained by oxidizing Si3N4).


Dielectric Constant Electric Charge Curie Temperature Deposition Temperature Storage Node 
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Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  1. 1.Advanced R&D CenterMitsubishi Electric Corp.AmagasakiJapan

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