Towards Plasma Enhanced Atomic Layer Deposition

The fabrication of microelectronics relies on thin film technologies. As the demand for improved performance of microchips continues to escalate, atomic layer deposition (ALD) has emerged as a crucial technique in enabling precise and controlled thin film deposition. Plasma-enhanced ALD in particular is an energy-enhanced method for synthesizing thin films with mono-layer resolution. Unlike conventional thermal ALD processes where chemical precursors react with a heated substrate to deposit the thin film, forming a plasma of the ALD precursors allows for alternate reaction paths, potentially leading to improved film density, crystallinity, and mechanical properties at lower deposition temperatures. Plasma exposure during ALD can also assist in the removal of surface contaminants during the deposition process. In this project, a capacitively coupled plasma is generated by applying a direct current (DC) bias between the powered and grounded electrodes in a quartz chamber, inducing an electric field. This couples with the precursor gas to create a high-energy plasma that produces energetic reactive species, which can then be directed to the substrate, providing novel reaction pathways having a more desired thermal budget to achieve the desired film properties. This chamber will be integrated into an ALD system to enable plasma-enhanced ALD. The chemical, physical, and electrical properties of the resulting films will be characterized