Atomic layer chemical vapor deposition of SiO2 thin films using a chlorine-free silicon precursor for 3D NAND applications. Issue 13 (1st July 2021)

• Record Type: Journal Article
• Authors: Baek, GeonHo; Baek, Ji-hoon; Kim, Hye-mi; Lee, Seunghwan; Jin, Yusung; Park, Hyung Soon; Kil, Deok-Sin; Kim, Sangho; Park, Yongjoo; Park, Jin-Seong
• Is Part Of: Ceramics international. Volume 47:Issue 13(2021)
• Page Start: 19036
• Page End: 19042
• Publication Date: 2021-07-01
• Subjects: Cl-free Si precursor -- High-temperature process -- Thermal atomic layer deposition -- 3D NAND flash memory -- Tunneling oxide layer; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2021.03.249
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Atomic layer deposition and atomic layer chemical vapor deposition (ALD, ALCVD) of SiO2 films were investigated over a wide range of high temperatures (from 525 °C to 700 °C) using chlorine-free amino silane as the Si precursor and O3 as the oxygen reactant. The ALD window occurred at 550–600 °C. The growth per cycle (GPC) of the SiO2 films was about 1.14–1.58 Å/cycle for deposition temperatures between 525 and 700 °C. There were no chlorine impurities detected in any of the deposited ALCVD films. Above a deposition temperature of 750 °C, the SiO2 films exhibited conventional chemical vapor deposition (CVD) behavior due to precursor decomposition, as evidenced by high GPC (5.51 Å/cycle) and a significant impurity content (carbon 0.2 at% and nitrogen 0.4 at%). The SiO2 films had high film density (2.3 g/cm 3 ), minimal roughness (rms ~ 0.16 nm). In addition, the wet etch rate (WER) of the SiO2 films decreased from 3.0 to 2.1 nm/min. The ALD SiO2 film at 600 °C exhibited excellent electrical performance, such as a leakage current density of 5.03 × 10 −9 A/cm 2 (at 3 MV/cm) and a breakdown field of 10.3 MV/cm.