Improvement of AlN Film Quality Using Plasma Enhanced Atomic Layer Deposition with Substrate Biasing

• Published in: ACS applied materials & interfaces Vol. 12; no. 35; pp. 39870 - 39880
• Main Authors: Legallais, Maxime, Mehdi, Hussein, David, Sylvain, Bassani, Franck, Labau, Sébastien, Pelissier, Bernard, Baron, Thierry, Martinez, Eugenie, Ghibaudo, Gérard, Salem, Bassem
• Format: Journal Article
• Language: English
• Published: American Chemical Society 02-09-2020; Washington, D.C. : American Chemical Society
• Subjects: Engineering Sciences; Micro and nanotechnologies; Microelectronics; Surfaces, Interfaces, and Applications; XPS; PEALD; aluminum nitride; ion energy; substrate biasing; MIS capacitors; 12; 39870−39880 Read Online Metrics & More Article Recommendations aluminum nitride; ACS Appl. Mater. Interfaces 2020
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.0c10515

In recent years, plasma enhanced atomic layer deposition (PEALD) has emerged as a key method for the growth of conformal and homogeneous aluminum nitride (AlN) films at the nanoscale. In this work, the utilized PEALD reactor was equipped not only with a traditional remote Inductively Coupled Plasma source but also with an innovative additional power supply connected to the substrate holder. Thus, we investigate here the substrate biasing effect on AlN film quality deposited on (100) silicon. We report that by adjusting the ion energy via substrate biasing, the AlN film quality can be significantly improved. Indeed, compared to films commonly deposited without bias, AlN deposited with a platen power of 5 W displays a 14% increase in the number of N–Al bonds according to X-ray spectroscopy analysis. Moreover, after having integrated them into Metal–AlN–Si capacitors, the 5 W AlN film exhibits a permittivity increase from 4.5 to 7.0 along with a drastic drop of leakage current density of more than 5 orders of magnitude. The use of substrate biasing during PEALD is thereby a promising strategy for the improvement of AlN film quality.