EUV underlayer materials for 22nm HP and beyond

Progress in EUV Underlayer Materials

“…19 All of AZ® EBL materials have EUV absorption ranging from 1.5/g to 8.0/g (Conventional ArF BARC AZ ® ArF-1C5D has a EUV absorption value of ~ 1.2/g). 16 The EBL underlayer can function well with a film thickness as low as 5 nm. For sub-30 nm imaging, the sensitivity of resist can be improved by more than 10% using EBL underlayer instead of conventional ArF BARC.…”

“…For our first generation of AZ ® EBL materials, ArF bottom antireflective coating (BARC) platform are used to reduce substrate reflectivity and enhance EUV imaging performance. 16 High EUV absorption elements are incorporated in polymer syntheses. However, ArF underlayer materials only have strong absorbance below 210 nm, the OOB radiation at longer wavelength especially from 220 nm -260 nm have not been absorbed sufficiently.…”

“…AZ ® EBL materials mostly are based on polymer matrix containing high EUV photon absorption (EPA) unit which can efficiently absorb and convert EUV photo energy to generate secondary electrons and eventually help produce photo acid in resists. 16 The polymer platform uses AZ's ArF bottom antireflective coating (BARC) platform. The structure of the polymer is displayed in Figure 1.…”

“…2 Several groups have developed underlayer materials that can improve sensitivity, pattern profile and processing in EUV lithography. [12][13][14][15][16] Our first generation of EUV underlayer materials AZ ® EBL are based on polymer matrix with high EUV photon Absorption. 16 The combination of increased total film absorbance (TFA) and antireflective properties in AZ ® EBL underlayers can effectively enhance the overall EUV performances.…”

“…[12][13][14][15][16] Our first generation of EUV underlayer materials AZ ® EBL are based on polymer matrix with high EUV photon Absorption. 16 The combination of increased total film absorbance (TFA) and antireflective properties in AZ ® EBL underlayers can effectively enhance the overall EUV performances. The EUV lithography on AZ ® EBL underlayers has improved sensitivity, imaging capability, dissolution contrast, resolution and process window.…”