Ebook: Plasma Etching Processes for Interconnect Realization in VLSI

This is the first of two books presenting the challenges and future prospects of plasma etching processes for microelectronics, reviewing the past, present and future issues of etching processes in order to improve the understanding of these issues through innovative solutions.

This book focuses on back end of line (BEOL) for high performance device realization and presents an overview of all etch challenges for interconnect realization as well as the current etch solutions proposed in the semiconductor industry. The choice of copper/low-k interconnect architecture is one of the keys for integrated circuit performance, process manufacturability and scalability.

Today, implementation of porous low-k material is mandatory in order to minimize signal propagation delay in interconnections. In this context, the traditional plasma process issues (plasma-induced damage, dimension and profile control, selectivity) and new emerging challenges (residue formation, dielectric wiggling) are critical points of research in order to control the reliability and reduce defects in interconnects. These issues and potential solutions are illustrated by the authors through different process architectures available in the semiconductor industry (metallic or organic hard mask strategies).

• Presents the difficulties encountered for interconnect realization in very large-scale integrated (VLSI) circuits
• Focused on plasma-dielectric surface interaction
• Helps you further reduce the dielectric constant for the future technological nodes

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Constraint Programming aims at solving hard combinatorial problems, with a computation time increasing in practice exponentially. The methods are today efficient enough to solve large industrial problems, in a generic framework. However, solvers are dedicated to a single variable type: integer or real. Solving mixed problems relies on ad hoc transformations. In another field, Abstract Interpretation offers tools to prove program properties, by studying an abstraction of their concrete semantics, that is, the set of possible values of the variables during an execution. Various representations for these abstractions have been proposed. They are called abstract domains. Abstract domains can mix any type of variables, and even represent relations between the variables.

In this work, we define abstract domains for Constraint Programming, so as to build a generic solving method, dealing with both integer and real variables. We also study the octagons abstract domain, already defined in Abstract Interpretation. Guiding the search by the octagonal relations, we obtain good results on a continuous benchmark. We also define our solving method using Abstract Interpretation techniques, in order to include existing abstract domains. Our solver, AbSolute, is able to solve mixed problems and use relational domains.

• Exploits the over-approximation methods to integrate AI tools in the methods of CP
• Exploits the relationships captured to solve continuous problems more effectively
• Learn from the developers of a solver capable of handling practically all abstract domains