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Among the chemistries/polymers reported for the 193nm photoresist applications, methacrylate copolymers consisting of 2-methyl-2-adamantane methacrylate (2-MadMA) and mevalonic lactone methacrylate (MLMA) and cycloolefin polymers derived from derivatives of norbornene have shown promising results. We have studied the lithographic properties of these two different promising chemistries. Both systems offer linear resolutions down to 130 nm dense lines using conventional 193 nm illumination and high sensitivity at standard developer conditions. The etch rates of the methacrylate and cycloolefin based resists for polysilicon were found to be 1.4 and 1.3 times higher than that of novolak resist. Calculation of the normalized image log-slope (MILS) for both resist types shows that they can still resolve aerial images with a NILS of about 1.0, which is also confirmed by their 248 nm performance. The potential of 193 nm lithography is estimated at 110 nm dense line resolution if resists can be improved to match the performance of dense line resolution if resists can be improved to match the performance of the best current 248 nm resists which can resolve NILS values of about 0.7

Hard masks used in lithography processes play a vital role in pattern transfer to the desired substrate. Hard mask materials can be categorized into organic and inorganic types. Examples of organic type hard masks include amorphous carbon, organo siloxane based materials with reflection control properties. These organic hard masks are deposited either by CVD process or spin-on processes. SiN, SiON and TiN are some examples of inorganic type hard masks and typically these hard masks are deposited through CVD process. In either type, key requirement is etch resistance to either oxygen rich plasma or halogen rich plasma depending on the substrate to be etched away. However, in the advanced lithography processes, in addition to good etch resistance, they also need to possess good wet removability, fill capability in high aspect ratio contacts and trenches. In this paper, we discuss the advances made in the spin-on organic and inorganic hard masks. The spin-on option provides high throughput and several alternate material options compared to CVD option. Spin-on carbon (SOC) is a high carbon containing polymer solution and as a coating material, the polymers need to be soluble in organic solvent and insoluble after curing for coating upper layer materials. Recent progress made in good filling, low outgas, high thermal stability and planarization properties required for double and quadruple patterning is presented. Similarly, novel spin-on type inorganic formulations providing Ti, W, and Zr oxide hard masks with high etch selectivity, wet removal capability and good shelf-life stability are described. These novel AZ ® Spin-on MHM formulations can be used in several new applications and can potentially replace any metal, metal oxide, metal nitride or silicon-containing hard mask films currently deposited using CVD process in the semiconductor manufacturing process.