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Semiconductor industries, mainly integrated circuit (IC), MEMS/NEMS (Micro/Nanoelectromechanical systems), III-V device and sensor manufacturers have successfully employed ALD for several years already in their manufacturing processes to realize a wide selection of electronics components and devices. Due to the constantly decreasing component/device size and at the same time, increased level of system integration, most of the conventional thin film manufacturing methods fall short when reliably uniform, dense, conformal and pinhole-, crack- and defect-free films have to be deposited on advanced modern electronics components. For example through-silicon-via contact metallizations or other thin films for high aspect ratio geometries common in today’s chip architectures are practically impossible to prepare evenly and conformally enough with other thin film deposition methods, e.g. PVD or CVD, whereas the ALD method’s gas-phase, surface-controlled and self-saturating nature ensures high quality film formation even on the most challenging nanoscale geometries. Gate dielectrics (e.g. Al2O3, Ta2O5 and HfO2) and metals, etch mask and etch-stop layers, metallic layers for contacts and charge dissipation, seed layers, anti-stiction layers, adhesion layers, nucleation layers for self-assembled monolayers (SAMs), hermetic layers, layers improving device quality by reducing the effect of wear, stress or friction, protective layers against electrical shorts, optical layers, filters, capacitors’ metal contact films and dielectric capacitive films, and sensor elements are just a few examples of ALD’s enormous potential and indispensability in this field.
And, to realize long and failure-free operating time of the semiconductor devices, ALD is the optimal method to isolate the components from environmental exposure (moisture, oxygen, impurities) by depositing a hermetic encapsulant coating on them.