Advanced patterning solutions based on the "shrink process assisted by double exposure" (SPADE)

Abstract

By combining chemical and thermal curing techniques, we developed a simple "hybrid" curing system which offers precise CD control of the first patterns after double patterning. This hybrid curing system involves thermal curing followed by a liquid rinse process using a double patterning primer (DPP). DPP is an aqueous solution formulated with surface curing agent (SCA) components and enhances "positive" interaction between L1 and L2 patterns. Taking advantage of the CD growth with DPP treatment, we further developed three advanced patterning schemes: 1. "Shrink Process Assisted by Double Exposure" (SPADE TM I Process), 2. "Space Patterning Assisted by Double Exposure" (SPADE II), and 3. "Sidewall Patterning Assisted by Double Exposure" (SPADE III). Using SPADE I, contact hole CD was reduced by 10~30nm and excellent through pitch performance was achieved. Using SPADE II, the first example of self-aligned double patterning of contact holes has been demonstrated. After SPADE II, the contact hole pitch was reduced by 30%. A novel method was developed to form sidewalls on the existing patterns using SPADE III. The 2D sidewall patterning with contact holes was demonstrated and ~40nm sidewalls were formed using SPADE III. This can also be applied to form sidewall patterns on line and space patterns to self-aligned double patterning of lines. In this paper, our recent progress with SPADE technology is described and its potential use in the advanced patterning schemes is discussed.Keywords: double patterning primer, self-aligned double patterning, SPADE, shrink process assisted by double exposure (SPADE I), space patterning assisted by double exposure (SPADE II), sidewall patterning assisted by double exposure (SPADE III),