Types of Resists
There are primarily two types of resists:
positive resists and
negative resists. Positive resists become soluble when exposed to radiation, while negative resists become insoluble.
Components of Resist Formulations
A typical resist formulation comprises three main components: Why is Resist Sensitivity Important?
Resist sensitivity determines how much exposure energy is required to induce the desired chemical changes. Higher sensitivity resists are preferred for
high-resolution applications as they require less energy and shorter exposure times.
Challenges in Resist Formulations
Formulating resists for nanotechnology presents unique challenges, such as: Line-edge roughness (LER): Variations at the edges of the patterns can affect device performance.
Resolution: Achieving smaller feature sizes without losing pattern fidelity.
Environmental stability: Resists must withstand various processing conditions, such as high temperatures and chemicals.
Advancements in Resist Technology
Recent advancements include the development of
EUV resists (extreme ultraviolet), which allow for even smaller feature sizes. Another promising area is the use of
nanocomposite resists, which incorporate nanoparticles to enhance performance.
Future Directions
The future of resist formulations lies in addressing current limitations and enhancing performance. This includes improving
etch resistance, reducing environmental impact, and developing new materials that can operate at even smaller scales.
