Chemically Amplified Resist Process Research Articles

Edge Roughness Study of Chemically Amplified Resist in Low-Energy Electron-Beam Lithography Using Computer Simulation

We investigated the line edge roughness (LER) of chemically amplified resist (CAR) in the high-sensitivity resist process in low-energy electron beam lithography (LEEBL). We have confirmed that a sub-100 nm pattern having a small line edge roughness could be obtained at the exposure dose below sub-1 µC/cm2 for LEEBL. In order to explain the experimental results, we have proposed a resist exposure model, considering the generation yield and diffusion of secondary electrons (SEs). Based on the proposed model, we analyzed the LER for LEEBL using a simulation. When the beam blur and the acceptable LER were 30 nm (σ) and 2 nm (σ), the acceptable exposure doses for 2–5 keV and 50 keV were 0.3 µC/cm2 and 2.5 µC/cm2, respectively. This means that a high-sensitivity CAR process at the exposure dose below 0.5 µC/cm2 can be achieved in LEEBL.

An optimization design method for chemically amplified resist process control

A novel optimization method called chemically-amplified resist process optimization design (CARPOD) applicable to the chemically amplified resist (CAR) process development is described. The method finds the optimal process conditions and the design center (maximum process tolerance space) of a CAR process with minimum experimental runs. First a modified response surface method is used to form the numerical response surface of a CAR, and its most sensitive point, which is the minimum requirement of X-ray dose, is located as an optimal process condition by an optimization method called POSM under the constraint of the contrast of the photoresist. Second, the design center is found to maximize the process tolerance space around the optimal process condition. Third, verifications are made on the optimal design as well as the design center. The process optimization of AZ PF-514 has been used as an example to show that the CARPOD method can identify the optimal process condition as well as the maximum tolerable parameter space with minimum experimental runs. >

Optimization design program for chemically amplified resist process

In this article, a novel optimization program applicable to chemically amplified resist (CAR) process development, which is based on the method named as chemically amplified resist process optimization design developed in CXrL, is described. This program is separated as three subprograms. The first program called vertices is used to find most efficient sampling space. The second program called OPTIM1 is used to find the optimal process conditions. The third program called OPTIM2 is used to find the design center (maximum process tolerance space) of a CAR process with minimum experimental runs. In this article, the process optimization of AZ PF-514 has been used as an example to show that the program can identify the optimal process condition as well as the maximum tolerable parameter space with minimum experimental runs.