Inhibitor-free area-selective atomic layer deposition of dielectrics via atomic layer nucleation engineering

Chun Yi Chou^1*, Yu-Tung Yin¹, Miin-Jang Chen¹

¹Materials Science and Engineering, National Taiwan University, Taipei, Taiwan

* Presenter:Chun Yi Chou, email:D07527011@ntu.edu.tw

With the rapid development of semiconductor technology, aggressive device scaling leads to high demand for area-selective atomic layer deposition (AS-ALD). In this article, a novel “atomic layer nucleation engineering (ALNE)” technique is proposed to achieve inhibitor-free AS-ALD of Al₂O₃ and AlN. The selectivity reaches ~100% between dielectric growth area (GA, SiO₂) and metal non-growth area (NGA, Pt) up to 100 ALD cycles. A radio-frequency substrate bias step (ALNE) is added after the precursor pulse and purge. The substrate bias generates plasma and control the plasma energy to remove the precursors on the NGA based on the relatively lower binding energy compared with that on the GA, as revealed by the first-principle calculation. Therefore, the film growth on NGA can be suppressed while that on GA still proceed, leading to AS-ALD. The critical ALNE step achieves AS-ALD with high thickness differences of ~8.7 and ~14.9 nm for AlN and Al₂O₃, respectively, between the GA and NGA surfaces. The novel ALNE technique is also capable of realizing AS-ALD of oxide and nitride on patterned substrates. The ALNE technique paves the way toward inhibitor-free AS-ALD, which is essential to the extension of Moore’s law.

Keywords: area-selective atomic layer deposition, atomic layer nucleation engineering, inhibitor-free, substrate biasing