Title :
Excellent low-pressure-oxidized Si3N4 films on roughened poly-Si for high-density DRAMs
Author :
Han-Wen Liu ; Huang-Chung Cheng
Author_Institution :
Dept. of Electron. Eng. & Inst. of Electron., Nat. Chiao Tung Univ., Hsinchu, Taiwan
Abstract :
High-reliability and good-performance stacked storage capacitors with high capacitance value of 17.8 fF/μm2 has been realized using low-pressure-oxidized thin nitride films deposited on roughened poly-Si electrodes. These novel electrodes are fabricated by H3PO4-etching and are RCA-cleaned. The leakage current density at +2.5 and -2.5 V are 0.07×10/sup -9/ and -2.4×10/sup -8/ A/cm2, respectively, fulfilling the requirements of 256 Mb DRAM´s. Weibull plots of time-dependent-dielectric-breakdown (TDDB) characteristics under constant current stress and constant voltage stress also show tight distribution and good electrical properties. Hence, this easy and simple technique is promising for future high-density DRAM´s applications.
Keywords :
DRAM chips; Weibull distribution; capacitors; dielectric thin films; electric breakdown; elemental semiconductors; integrated circuit reliability; leakage currents; silicon; silicon compounds; -2.5 to 2.5 V; 256 Mbit; Si/sub 3/N/sub 4/-Si; Weibull plots; capacitance value; constant current stress; constant voltage stress; high-density DRAM; leakage current density; reliability; stacked storage capacitors; time-dependent-dielectric-breakdown; Capacitance; Capacitors; Dielectric materials; Electrodes; High-K gate dielectrics; Leakage current; Material storage; Random access memory; Semiconductor films; Stress;
Journal_Title :
Electron Device Letters, IEEE
