Integrated in situ self-aligned double patterning process with fluorocarbon as spacer layer

Abstract

Self-aligned double patterning (SADP), or spacer lithography, is a widely used technique in the semiconductor industry for high-throughput nanoscale pattern definition and thus is of great significance for very-large-scale integration, large-area photonic device fabrications, and other applications. In a standard SADP flow, chemical vapor deposition or atomic layer deposition is used to deposit a conformal spacer layer, which is typically a dielectric material. The spacer composition and film quality will influence downstream critical dimension control. However, samples have to go through multiple processing environments, and fabrication complexity is thus increased. In this work, an in situ SADP process is proposed, with all the fabrication steps being integrated into a single process inside a commercially available plasma etching equipment. The spacer layer is a plasma-deposited fluorocarbon film, which has a uniform step coverage and a good etch selectivity to silicon. Various nanostructures have been fabricated to prove the capability of this technique. With its high integrity and technical convenience, this method can be promising to improve the throughput and efficiency of nanofabrication in the semiconductor industry, microelectromechanical systems, and photonic engineering.

Flexible BioMEMS devices enabled by micromachining of plasma-polymerized fluorocarbon

“…Firstly, PPFC is deposited on a pristine Si wafer by C 4 F 8 -based plasma with a commercially available plasma etching system (a), the deposition mechanism is similar as a plasmaenhanced chemical vapor deposition (PECVD) process and has been investigated in previous studies by the authors. [16] Before further processes, the samples are baked above the glass transition temperature of PPFC (around 115 • C [17]) to reduce the surface roughness and the primary polymers on the PPFC surface. Patterns are then defined with standard UV lithography method (b1/b2), and PPFC is not dissolved or eroded by photoresist or developer due to its chemical inertness.…”

Thermal Reflow of Plasma-Polymerized Fluorocarbon for Nanochannels and Particle Encapsulation

“…The deposition rate is estimated to be around 400 nm/min, which is measured by a spectroscopic ellipsometry system (Ellipsometer VASE, J. A. Woolam), and the PPFC deposition mechanism has been discussed in detail in previous studies [16]. Thermal treatments were performed by a hotplate with various temperatures.…”

Plasma-Assisted Microcontact Printing

“…Normally, these processes apply liquid-based ink solutions, which can be transported to substrate surfaces by chemical bonds, diffusions, or fluid dynamical processes, and sub-micrometer feature sizes have been demonstrated on a wafer scale. Specifically, PPL has attracted a lot of research interests by combining μCP and dip pen lithography (DPL), , and multiple modified versions have been developed on the basis of novel ink materials or new duplication mechanisms. − …”