Title :
Deposition of uniform Zr-Sn-Ti-O films by on-axis reactive sputtering
Author :
van Dover, R.B. ; Schneemeyer, L.F.
Author_Institution :
Lucent Technol., AT&T Bell Labs., Murray Hill, NJ, USA
Abstract :
We describe the deposition of amorphous Zr-Sn-Ti-O (aZTT) dielectric thin films using conventional on-axis reactive sputtering. Thin films of composition Zr/sub 0.2/Sn/sub 0.2/Ti/sub 0.6/O2 have excellent dielectric properties: 40-50-nm thick films with a dielectric constant of 50-70 were obtained, depending on the processing conditions, yielding a specific capacitance of 9-17 fF/μm2. Breakdown fields were measured to be 3-5 MV/cm, yielding a figure of merit /spl epsi//spl epsi/0E/sub br/=15-30 μC/cm2, up to eightfold higher than conventional deposited SiO2. Leakage currents, measured at 1.0 MV/cm, were in the range 10/sup -9/-10/sup -7/ A/cm2. This material appears well-suited for use in Si-IC device technology, for example as storage capacitors in DRAM.
Keywords :
DRAM chips; capacitors; dielectric thin films; electric breakdown; leakage currents; permittivity; sputter deposition; tin compounds; zirconium compounds; 40 to 50 nm; DRAM; IC device technology; Zr/sub 0.2/-Sn/sub 0.2/Ti/sub 0.6/O/sub 2/-Si; breakdown fields; dielectric constant; dielectric thin films; leakage currents; on-axis reactive sputtering; specific capacitance; storage capacitors; Amorphous materials; Capacitance; Dielectric constant; Dielectric thin films; Electric breakdown; Material storage; Sputtering; Thick films; Tin; Zirconium;
Journal_Title :
Electron Device Letters, IEEE
