A comparison of SALELE with traditional lithography and anti-spacer technology

Advanced patterning solutions, such as spacer-assisted pitch splitting, have enabled continuous scaling in the face of delayed introduction of next lithography wavelengths and technologies for the past couple decades. Self-aligned double patterning (SADP)[ref] and self-aligned litho-etch-litho-etch (SALELE)2 are two such solutions, where the greatest utility comes from the ability to self-align features; however, these techniques require deposition and etch of multiple materials, which reduces throughput and increases manufacturing costs compared to directly printing the desired feature. Anti-spacer technology1,[ref], on the other hand, enables both self-aligned pitch splitting and high throughput via a single pass track-based process. In this work, we are comparing a manufacturing flow for a SALELE [2] process with traditional lithography vs an Anti-spacer technology based SALELE Process in details. Using an anti-spacer technology for lithography gives a huge relief in initial litho CD resulting in a quarter of the design pitch with Anti-spacer technology vs half the design pitch with traditional lithography. This will help with CDU, LER and Stochastics to reduce defectivity. Starting with layout decomposition, where the drawn layer is decomposed into 4 Masks: 2 Metal-like Masks, and 2 Block-like Masks. Then each of these masks is subjected to Optical Proximity Correction (OPC) process, and here we explain more about the OPC recipe development for each mask. We will then compare the two process for variation and EPE verification the OPC verification