Titanium oxide film for the bottom antireflective layer in deep ultraviolet lithography

Byung-Hyuk Jun, Sang-Soo Han, Kyong-Sub Kim, Joon-Sung Lee, Zhong-Tao Jiang, Byeong-Soo Bae, Kwangsoo No, Dong-Wan Kim, Ho-Young Kang, Young-Bum Koh
1997 Applied Optics  
Titanium oxide thin film, fabricated with tetraisopropyltitanate and oxygen by electron cyclotron resonance-plasma-enhanced chemical vapor deposition, is investigated as a potential candidate for the antireflective layer in KrF excimer laser ͑248-nm͒ lithography. The oxygen flow-rate dependence of the optical properties such as the refractive index ͑n͒ and the extinction coefficient ͑k͒ of the film at the 248-nm wavelength has been characterized, and the films with the expected combinations of
more » ... ed combinations of n and k values for the antireflective layer have been deposited. Simulation results indicate that reflectance values of less than 4% and as low as 1.2% can be reached at the interface between the photoresist and the film postulating the structures of the photoresist͞300-Å TiO x film͞c-Si substrate and the W-Si substrate, respectively, by selected proper combinations of n and k values. Moreover the reflectance can be further reduced to almost zero by changing the film thickness. Thus it is found that titanium oxide thin films can be used as the bottom antireflective layer in KrF excimer laser lithography.
doi:10.1364/ao.36.001482 pmid:18250825 fatcat:ov2ituv2cjgefov5r4yeeudglu