Advanced Metal Gate Electrode Options Compatible with ALD and AVD® HfSiOx-Based Gate Dielectrics

Abstract

We have investigated metal gate electrodes for use with high k HfSiOx gate dielectric films using AVD ® and ALD technology. First, we report on the characterization of the AVD ® and ALD deposition techniques where both HfO 2 and SiO 2 are combined for the formation of HfSiOx. Nitrogen is then incorporated using both in-situ and ex-situ methods to form HfSiON and the resulting film properties are compared. Using an AVD process a work-function of >4.7eV for Ru and RuO 2 gate electrode metals in combination with HfSiOx was obtained. A TaN-based metal gate was also characterized to target a promising pMOS solution using different compositions. Together with its high flexibility and composition control, both ALD and AVD ® can become key processes for advanced high-k dielectrics as well as compatible CMOS metal electrodes.

(Invited) Innovative Deposition Technology for Advanced Materials

“…The evaporated precursor is then transported into a showerhead and mixed with reactive gases to allow deposition of multi-component materials with high throughput and precise composition control even for metal-organic precursors with low volatility, low thermal stability and instability in air (9,10). AVD and ALD using this vaporizer technology have been reported for deposition of HfSiOx based gate dielectrics (11) and TaCN based gate metal electrodes (12).…”

AVD and MOCVD TaCN-based Films for Gate Metal Applications on High k Gate Dielectrics

“…Obtaining PMOS solutions has been a challenge to meet band-edge work function of ~5.2eV. In the case of high k dielectric in combination with a metal, ruthenium has been reported as one promising p-type gate metal candidate, with its work function in the order of ~5.2eV (2). By optimizing AVD process conditions, a work function of >5.2 eV for Ru and RuO 2 was obtained.…”