Effects of Post-Deposition Annealing on the Electrical Properties of HfSiO Films Grown by Atomic Layer Deposition

Abstract

Post-deposition annealing was investigated for hafnium silicate films deposited on Si substrates by atomic layer deposition. Annealing in NH3 at 750°C incorporated 13 At.% nitrogen in hafnium silicate, and hysteresis significantly depended on film thickness. In contrast, annealing in N2 at 950°C suppressed hysteresis and its dependence on the film thickness. In addition, effective mobility and positive bias temperature instability were improved by N2 annealing of as-deposited hafnium silicate films. Finally, additional N2 annealing following NH3 annealing was effective to obtain highly dense hafnium silicate films with good mobility and optimized nitrogen incorporation.

Electrical Characterization of Ti–Silicate Films Grown by Atomic Layer Chemical Vapor Deposition

“…[1][2][3][4][5][6][7][8][9][10] The scaling has led to the development of MOSFETs with ultra-short physical gate lengths (<50 nm) and insulating SiO 2 -based films with a thickness of less than 1 nm. At such a thickness, these films suffer from excessively high leakage of charge carriers and poor reliability with respect to dielectric breakdown.…”

“…The study of ultrathin gate dielectrics has recently gained much attention due to the technological need to replace SiO 2 films in metal-oxide-semiconductor field-effect transistors (MOSFETs). [1][2][3][4][5][6][7][8][9][10] The scaling has led to the development of MOSFETs with ultra-short physical gate lengths (<50 nm) and insulating SiO 2 -based films with a thickness of less than 1 nm. At such a thickness, these films suffer from excessively high leakage of charge carriers and poor reliability with respect to dielectric breakdown.…”

Growth and Characterization of Hf–Silicate/Al2O3 Gate Stacks Grown on Si(100) by Self-Limiting Atomic Layer Deposition

“…Materials with a higher dielectric constant (k) have been widely studied because with them, thicker films can be used than with lower-dielectric SiO 2 . [1][2][3][4][5][6][7] Alternative dielectrics such as Ta 2 O 5 , 3) TiO 2 , 4) Al 2 O 3 , 5) ZrO 2 , 6) HfO 2 , 7) and their related silicates 4) or aluminates 1) have been investigated. However, most of these films, except Al 2 O 3 , silicates and aluminates, are not thermally stable (due to crystallization and interfacial layer formation) and show low phase transition temperatures from the amorphous to the crystalline structures.…”

“…However, most of these films, except Al 2 O 3 , silicates and aluminates, are not thermally stable (due to crystallization and interfacial layer formation) and show low phase transition temperatures from the amorphous to the crystalline structures. [1][2][3][4][5][6][7] Al 2 O 3 films have been investigated as a good candidate because of their chemical and thermal stabilities, and high field strength. Also, Al 2 O 3 has a relatively high band gap (8.8 eV) and is a good barrier to ionic transport.…”

Highly Conformal Hafnium Silicate Film Growth by Atomic-Layer Chemical Vapor Deposition using a New Combination of Precursors: Hf(OC(CH3)3)4 and Si(N(CH3)(C2H5))4

“…In MOCVD or ALCVD, the growth and properties of films are strongly affected by the precursors used, because the film deposition is predominantly based on the chemical reaction between precursors. 6,8,[12][13][14][15] In this work, ultra thin hafnium silicate film was deposited by ALCVD using a new combination of precursors: tetrakisethylmethylaminosilane [Si(N(CH 3 )(C 2 H 5 )) 4 ] and hafnium tetra-tert-butoxide [Hf(OC(CH 3 ) 3 ) 4 ]. We chose Si(N(CH 3 )-(C 2 H 5 )) 4 as a Si precursor to minimize carbon and chlorine contaminations in the films grown.…”