Film properties of ALD HfO2 and La2O3 gate dielectrics grown on Si with various pre-deposition treatments

In this article, we report film properties of HfO2 and La2O3 gate dielectrics grown on Si(100) substrate using atomic layer deposition (ALD) with various surfaces modified before film growth. The precursors used for HfO2 and La2O3 films are hafnium tetrachloride (HfCl4), lanthanum tris[bis(trimethylsilyl)amide] (C18H54N3LaSi6) and water. Pre-deposition treatments examined for HfO2 dielectric films include (1) surface nitridation using NH3, N2O, or NO, (2) substrate annealing in an oxidizing or reducing ambient, and (3) surface fluorination. These results were compared to those obtained using established approaches of growing HfO2 on an OH terminated surface produced chemically. Linear film growth was observed for the HfO2 with all pre-deposition treatments. Time-of-flight-secondary ion mass spectrometry (TOF-SIMS) and transmission electron microscopy (TEM) analysis indicated that all pre-treatments result in good film coverage with no interaction between HfO2 and silicon at the silicon substrate. The as d...

[1]  Angus I. Kingon,et al.  High temperature stability in lanthanum and zirconia-based gate dielectrics , 2001 .

[2]  E. Suzuki,et al.  MOCVD of High-Dielectric-Constant Lanthanum Oxide Thin Films , 2003 .

[3]  Raghaw Rai,et al.  Compatibility of polycrystalline silicon gate deposition with HfO2 and Al2O3/HfO2 gate dielectrics , 2002 .

[4]  Martin L. Green,et al.  Mathematical description of atomic layer deposition and its application to the nucleation and growth of HfO2 gate dielectric layers , 2003 .

[5]  D. Gilmer,et al.  Theoretical and experimental investigation of boron diffusion in polycrystalline HfO2 films , 2002 .

[6]  Wilfried Vandervorst,et al.  Nucleation and growth of atomic layer deposited HfO2 gate dielectric layers on chemical oxide (Si–O–H) and thermal oxide (SiO2 or Si–O–N) underlayers , 2002 .

[7]  O. Richard,et al.  TOF-SIMS as a rapid diagnostic tool to monitor the growth mode of thin (high k) films , 2003 .

[8]  A. Ogura,et al.  Evaluation of HfO2 film structures deposited by metal-organic chemical vapor deposition using Hf(N(C2H5)2)4/O2 gas system , 2003 .

[9]  Impact of metal–oxide gate dielectric on minority carrier lifetime in silicon , 2002 .

[10]  S. Rhee,et al.  Deposition of La2 O 3 Films by Direct Liquid Injection Metallorganic Chemical Vapor Deposition , 2002 .

[11]  H. Iwai,et al.  Characterization of La2 O 3 and Yb2 O 3 Thin Films for High-k Gate Insulator Application , 2003 .

[12]  D. Schlom,et al.  Thermodynamic stability of binary oxides in contact With silicon , 1996 .

[13]  M. Ramon,et al.  HfO2 Gate Dielectrics Deposited via Tetrakis Diethylamido Hafnium , 2003 .

[14]  Raghaw Rai,et al.  Thermodynamic stability of high-K dielectric metal oxides ZrO2 and HfO2 in contact with Si and SiO2 , 2002 .

[15]  R. Wallace,et al.  High-κ gate dielectrics: Current status and materials properties considerations , 2001 .

[16]  Eduard A. Cartier,et al.  Atomic beam deposition of lanthanum- and yttrium-based oxide thin films for gate dielectrics , 2000 .

[17]  M. Ritala,et al.  Rare-earth oxide thin films as gate oxides in MOSFET transistors , 2003 .

[18]  R. Gordon,et al.  Vapor Deposition of Metal Oxides and Silicates: Possible Gate Insulators for Future Microelectronics , 2001 .

[19]  E. Cartier,et al.  Formation of a stratified lanthanum silicate dielectric by reaction with Si(001) , 2001 .