Picosun Group, a provider of atomic layer deposition (ALD) equipment based in Finland, and the Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO) report that Picosun’s plasma-ALD technology successfully deposited a high-quality thin-film titanium nitride (TiN). Since the beginning of 2017. SINANO and Picosun have collaborated to develop advanced high-electron-mobility transistors (HEMTs), laser diodes, and lithium-ion batteries utilizing ALD in their joint lab in Suzhou.
SINANO and Picosun say TiN Deposition Requires Right Conditions and Manufacturing Method
SINANO wanted to avoid the performance drawbacks of using pure metals such as titanium as the ohmic contact between the metallic and semiconductor layers. For this reason, SINANO proposed titanium nitride (TiN) as a substitute. TiN is also metallic, and its conductivity and thermal stability are better than those of pure titanium metal. However, the conditions and manufacturing method are critical in obtaining high-quality TiN films.
Picosun says that its remote plasma ALD (RPEALD) provides a superior method for fabricating high-quality TiN thin films. The company’s approach positions the plasma source far enough from the substrate so that instead of energetic ion bombardment, the highly reactive radicals react at the substrate surface. This surface reactivity allows low process temperatures but does not cause the thermal stress or physical ion damage to the substrate. It also enables the deposition of conductive materials without the risk of short-circuiting or gas back-diffusion into the plasma source.
The proper selection of the precursor chemicals and the plasma gases ensures high purity TiN films. Furthermore, the process can be used on a large variety of substrate materials because the process works with a broad range of parameters and temperatures.
Prof. Sunan Ding from the Nano-X lab of SINANO noted the scalability of taking the processes to production scale due to the same core design of the R&D units and full-scale industrial production platforms.