Reliability of MIM HAO capacitor for 70nm DRAM

In order to verify the package reliability of a MIM HAO capacitor module, mass production 256M DDR processes with 0.1 /spl mu/m design rule were adopted. The capacitor dielectrics used were HAH and Hf/sub x/Al/sub y/O/sub z/ and showed Tox.eq of 12/spl Aring/ and Lc of<0.2 fA/cell, respectively. With proper thermal compensation for adjusting the cell Vt, we could get a high probe test yield, and high package yield when a MIM HAO capacitor was introduced instead of an SIS Al/sub 2/O/sub 3/ capacitor. With package samples, the refresh time of the device did not degrade after IR and EFR stresses, and finally, we could confirm the reliability of MIM HAO capacitors at package level through long term operation lifetime testing.