Mechatronic Spatial Atomic Layer Deposition for Closed-Loop and Customizable Process Control

A customized atmospheric-pressure spatial atomic layer deposition (AP-SALD) system is designed and implemented, which enables mechatronic control of key process parameters, including gap size and parallel alignment. A showerhead depositor delivers precursors to the substrate while linear actuators and capacitance probe sensors actively maintain gap size and parallel alignment through multiple-axis tilt and closed-loop feedback control. Digital control of geometric process variables with active monitoring is facilitated with a custom software control package and user interface. AP-SALD of TiO2 is performed to validate self-limiting deposition with the system. A novel multi-axis printing methodology is introduced using x-y position control to define a customized motion path, which enables an improvement in the thickness uniformity by reducing variations from 8% to 2%. In the future, this mechatronic system will enable experimental tuning of parameters that can inform multi-physics modeling to gain a deeper understanding of AP-SALD process tolerances, enabling new pathways for non-traditional SALD processing that can push the technology towards large-scale manufacturing. A customized atmospheric-pressure spatial atomic layer deposition (AP-SALD) system enables mechatronic control of key process parameters. Sensors and actuators actively monitor and adjust the gap size and relative alignment between the depositor and substrate in real time with closed-loop control. TiO2 films are deposited, and film uniformity is improved with multi-axis printing to define a customized motion path. image