Amorphous Carbon Layer (ACL) and SiON system has been proven to be a good hardmask
combination. These layers are formed by a high cost, low throughput CVD process. This paper discloses a
reliable, low cost, high throughput process using a simple spin on layer structure. Through manipulation of
various parameters, additional BARC layer is eliminated and the process is further simplified to a tri-layer
structure. Also, PR/SiON/C-SOH (Carbon-Spin-On-Hardmask) system has been compared to PR / Si-SOH
(Si-Spin-On-Hardmask ) / C-SOH system and found their performances are comparable. This indicates the
PR / Si-SOH / C-SOH process is an economical yet comparable substitute.