Generating sub-30-nm polysilicon gates using PECVD amorphous carbon as hardmask and anti-reflective coating

Atomic layer deposition for nonconventional nanomaterials and their applications

“…a-C, a randomly hybridized carbon with sp 3 and sp 2 configurations, is one of the most fascinating materials for the hard mask for multiple patterning processes [44,45,46], owing to its etch selectivity, hardness, and cost-effectiveness. As devices are being scaled down, photolithography encounters the physical limitation for sub-40 nm device fabrication [47,48].…”

“…In this patterning process, a-C is an essential material since a-C hard mask can resist any dry etch chemistry during the multiple patterning process with its superior etch selectivity, and it can be simply removed by oxygen plasma ashing without leaving behind any residue [49,50,51,52]. Currently, most of the a-C deposition is conducted by plasma-enhanced chemical vapor deposition (PE-CVD), which ensures high-throughput [45,51]. As technology node decreases to the sub-10-nm scale, a further complex patterning process, i.e., quadruple, sextuple, or octuple patterning, is required [53,54], and a deposition technique that ensures excellent conformality on the high-aspect-ratio structure spacer is needed for a-C deposition.…”

Beyond k1=0.25 lithography: 70-nm L/S patterning using KrF scanners

“…These materials have very high etching selectivity against the target films and they can be easily stripped away after target film etching. 3 The thin film thicknesses of APF TM (550Å) and DARC (250Å) are also helpful for this double exposure approach because the second lithography step only needs to image patterns over 800Å after-etch topography. The first etch and resist stripping process do not have any serious impact to the DARC and APF TM film.…”

Effect of N doping on the microstructure and dry etch properties of amorphous carbon deposited with a DC sputtering system

“…However, amorphous carbon lms fabricated through PE-CVD inevitably contain hydrogen due to the CH-based precursor, which causes degradation of the physical properties according to the hydrogen concentration, making it challenging to obtain high-aspect-ratio patterning. [10][11][12][13][14] To overcome this problem and improve the performance of the hardmask, studies have been conducted to predict a method that may have high resistance to uorine, a major etching gas, through DFT calculation. As a result of the calculation, a method of controlling the amount of hydrogen bonded to carbon or doping other substances was suggested.…”