Electrical Evaluation of Defects at the Si ( 100 ) / HfO2 Interface

This work examines the electrical activity of defects at the interface with Si(100) for HfO 2 thin films (10-20 nm) deposited by injection metal oxide chemical vapor deposition. Based on an analysis of the capacitance-voltage response of gold/HfO 2 /Si( 100) structures, two clear peaks are detected in the interface state density profiles, at specific energies in the lower (E v + 0.22-0.28 eV) and upper (E v + 0.93-0.97 eV) bandgap. The densities of defects responsible for these peaks have been calculated as 1.8-2.4 × 10 12 and 7.3-9.1 × 10 12 cm -2 , respectively. These defects are present when the HfO 2 films were deposited at sufficiently low temperatures (T ≤ 350°C) to prevent hydrogen passivation. The density of interface defects was not significantly different for HfO 2 films deposited on native oxide or hydrogen-terminated silicon surfaces. The position of these defects in the silicon bandgap corresponds to the location of P b0 (/P b1 ) dangling bond defects in the thermally oxidized Si(100)/SiO 2 system. HfO 2 films deposited at 450°C did not exhibit the prominent interface defects observed on films deposited at T ≤ 350°C, indicating hydrogen passivation during deposition.

[1]  A. Stesmans,et al.  Si dangling-bond-type defects at the interface of (100)Si with ultrathin HfO2 , 2003 .

[2]  B. O’Sullivan,et al.  Analysis of Pb centers at the Si(111)/SiO2 interface following rapid thermal annealing , 2003 .

[3]  John F. Conley,et al.  Electron spin resonance study of interface defects in atomic layer deposited hafnium oxide on Si , 2002 .

[4]  Andre Stesmans,et al.  Model for interface defect and positive charge generation in ultrathin SiO2/ZrO2 gate dielectric stacks , 2002 .

[5]  J. Cantin,et al.  An electron paramagnetic resonance study of the Si(100)/Al2O3 interface defects , 2002 .

[6]  B. O’Sullivan,et al.  Examination of the Si ( 111 ) ­ SiO2 , Si ( 110 ) ­ SiO2 , and Si ( 100 ) ­ SiO2 Interfacial Properties Following Rapid Thermal Annealing , 2002 .

[7]  Eduard A. Cartier,et al.  Materials characterization of ZrO2–SiO2 and HfO2–SiO2 binary oxides deposited by chemical solution deposition , 2001 .

[8]  V. Afanas’ev,et al.  Electron spin resonance observation of Si dangling-bond-type defects at the interface of (100) Si with ultrathin layers of SiOx, Al2O3 and ZrO2 , 2001 .

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

[10]  B. O’Sullivan,et al.  Si(100)–SiO2 interface properties following rapid thermal processing , 2001 .

[11]  V. Afanas’ev,et al.  Defects at the interface of ultra-thin VUV-grown oxide on Si studied by electron spin resonance , 2000 .

[12]  Car,et al.  Dangling bond defects at Si-SiO2 interfaces: atomic structure of the P(b1) center , 2000, Physical review letters.

[13]  Catherine Dubourdieu,et al.  Pulsed injection MOCVD of functional electronic oxides , 2000 .

[14]  V. Afanas’ev,et al.  Electrical activity of interfacial paramagnetic defects in thermal (100) Si/SiO2 , 1998 .

[15]  James H. Stathis,et al.  Potential fluctuations due to P b centres at the Si SiO 2 interface , 1997 .

[16]  Stesmans.  Relationship between stress and dangling bond generation at the (111)Si/SiO2 interface. , 1993, Physical review letters.

[17]  E. Poindexter,et al.  MOS interface states: overview and physicochemical perspective , 1989 .

[18]  N. Johnson,et al.  Interface traps and Pb centers in oxidized (100) silicon wafers , 1986 .