Interface chemistry of pristine TiN/La: Hf 0.5 Zr 0.5 O 2 capacitors

W. Hamouda (1, 2) , C. Lubin (1, 2) , S. Ueda (3) , Y. Yamashita (4) , O. Renault (5) , F. Mehmood (6) , T. Mikolajick (6) , U. Schroeder (6) , R. Negrea (7) , N. Barrett (1, 2)

1 SPEC - UMR3680 - Service de physique de l'état condensé
2 LENSIS - Laboratoire d'Etude des NanoStructures et Imagerie de Surface
3 RIKEN RSC - RIKEN SPring-8 Center [Hyogo]
4 NIMS - National Institute for Materials Science
5 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information
6 NaMLab gGmbH
7 National Institute for Materials Physics - NIMP (ROMANIA)

We present a hard and soft x-ray photoelectron spectroscopy study of the interface chemistry in pristine TiN/La-doped Hf0.5Zr0.5O2/TiN capacitors. An oxynitride phase (∼1.3 nm) is formed at the top interface, while a TiO2−delta phase was detected near the bottom interface. The oxygen vacancy (VO) concentration is higher at the top interface than in the film due to oxygen scavenging by the top electrode. The VO concentration was also found to increase from ∼1.5 to 1.9 × 1020 cm−3 when increasing La doping from 1.7 to 2.7 mol. %. Two La dopants are compensated by the formation of one positively charged VO.

Domains: Materials; Physics [physics]; Chemical Sciences

W. Hamouda, C. Lubin, S. Ueda, Y. Yamashita, O. Renault, et al.. Interface chemistry of pristine TiN/La: Hf 0.5 Zr 0.5 O 2 capacitors. Applied Physics Letters, 2020, 116 (25), pp.252903. ⟨10.1063/5.0012595⟩. ⟨cea-03695427⟩