Title :
The honeycomb-shape capacitor structure for ULSI DRAM
Author :
Yu, Sanggi ; Chun, Kukjin ; Lee, Jong Duk
Author_Institution :
Dept. of Electron. Eng., Seoul Nat. Univ., South Korea
Abstract :
A way to increase the charge stored in polysilicon capacitors using surface modulation technology is proposed. Asperities on the polysilicon surface are achieved by reactive ion etching (RIE) of the polysilicon, using the oxide at the grain boundary as a mask. The fabricated polysilicon electrode has a honeycomb shape. With this structure, the capacitance is increased by four times for a polysilicon storage electrode of 250-nm thickness. The leakage current is comparable to that of convection stacked capacitors (STCs).<>
Keywords :
DRAM chips; MOS integrated circuits; VLSI; capacitors; elemental semiconductors; leakage currents; silicon; sputter etching; surface treatment; 250 nm; RIE; Si; ULSI DRAM; honeycomb-shape capacitor structure; leakage current; polysilicon electrode; reactive ion etching; surface modulation technology; Capacitance; Capacitors; Electrodes; Etching; Fabrication; Grain boundaries; Oxidation; Random access memory; Semiconductor device doping; Ultra large scale integration;
Journal_Title :
Electron Device Letters, IEEE
