Molecular Glass Resists Based on Tetraphenylsilane Derivatives: Effect of Protecting Ratios on Advanced Lithography

Abstract

A series of t -butyloxycarbonyl ( t -Boc) protected tetraphenylsilane derivatives (TPSi-Boc x , x = 60, 70, 85, 100%) were synthesized and used as resist materials to investigate the effect of t -Boc protecting ratio on advanced lithography. The physical properties such as solubility, film-forming ability, and thermal stability of TPSi-Boc x were examined to assess the suitability for application as candidates for positive-tone molecular glass resist materials. The effects of t -Boc protecting ratio had been studied in detail by electron beam lithography. The results suggest that the TPSi-Boc x resist with different t -Boc protecting ratios exhibit a significant change in contrast, pattern blur, and the density of bridge defect. The TPSi-Boc 70% resist achieves the most excellent patterning capability. The extreme ultraviolet (EUV) lithography performance on TPSi-Boc 70% was evaluated by using the soft X-ray interference lithography. The results demonstrate that the TPSi-Boc 70% resist can achieve excellent patterning capability down to 20 nm isolated lines at 8.7 mJ/cm 2 and 25 nm dense lines at 14.5 mJ/cm 2 . This study will help us to understand the relationship between the t -Boc protecting ratio and the patterning ability and supply useful guidelines for designing molecular resists.

Nonchemically Amplified Molecular Resists Based on Sulfonium-Functionalized Sulfone Derivatives for Sub-13 nm Nanolithography

“…Several materials, including calixarene derivatives, , polyphenols, Noria molecules, , and fullerene derivatives, have been explored as MG resists in EUV or e-beam lithography. Our recent work has led to the development of a series of MG resists based on bisphenol A, spirobifluorene, tetraphenylsilane, and adamantane derivatives , for EUV and electron beam lithography (EBL), successfully delivering patterns with high resolution and low LER. Most of the research focused on molecular CAR, while non-CAR based on MGs is relatively unexplored.…”

A Single-Component Molecular Glass Resist Based on Tetraphenylsilane Derivatives for Electron Beam Lithography

“…The modification of TPSi is facile. 48 , 49 Our recent research has demonstrated that MG resists based on TPSi derivatives exhibit excellent thermal stability, film-forming ability, and high-resolution pattern performances. 49 Further, a new strategy of dual-tone developed molecular resists was proposed in our report, demonstrating a promising method to improve overall lithographic performance.…”

“… 48 , 49 Our recent research has demonstrated that MG resists based on TPSi derivatives exhibit excellent thermal stability, film-forming ability, and high-resolution pattern performances. 49 Further, a new strategy of dual-tone developed molecular resists was proposed in our report, demonstrating a promising method to improve overall lithographic performance. 50 As a continuation, a novel PAG-bound MG (TPSiS) was designed and prepared by modifying TPSi with eight t -butyloxycarbonyl ( t -Boc) groups and one sulfonium salt unit ( Figure 1 ).…”

Chemically Amplified Molecular Glass Photoresist Regulated by 2-Aminoanthracene Additive for Electron Beam Lithography and Extreme Ultraviolet Lithography

“…PAG is a photosensitive compound; in the post exposure baking (PEB) process, it will stimulate the reaction of the acid sensitive group on the main chain of the resin and generate new acid components. To improve lithography performance, the development of more advanced photoresist materials is significant. − Lawson’s team designed molecules with epoxy structure and used them for negative-tone photoresist. − After exposure, PAGs generate photoacid and catalyze the self-cross-linking reaction of the epoxy compounds, finally forming a dense network which drives the solubility switch. In addition, the huge cross-linked network can effectively improve the mechanical properties of the photoresist.…”