DRE: A Framework for Early Co-Evaluation of Design Rules, Technology Choices, and Layout Methodologies

Abstract

Abstract-Design rules have been the primary contract between technology developers and designers and are likely to remain so to preserve abstractions and productivity. While current approaches for defining design rules are largely unsystematic and empirical in nature, this paper offers a novel framework for early and systematic evaluation of design rules and layout styles in terms of major layout characteristics of area, manufacturability, and variability. The framework essentially creates a virtual standard-cell library and performs the evaluation based on the virtual layouts. Due to the focus on the exploration of rules at an early stage of technology development, we use first order models of variability and manufacturability (instead of relying on accurate simulation) and layout topology/congestion-based area estimates (instead of explicit and slow layout generation). Such a framework can be used to co-evaluate and co-optimize design rules, patterning technologies, layout methodologies, and library architectures.

Layout pattern-driven design rule evaluation

“…In our previous work, 1 we proposed DRE, a framework for the systematic evaluation of design rules, layout styles, and library architectures. However, DRE was not pattern-aware, and hence, we propose pattern-DRE in this work.…”

“…We use the device-layers generator of DRE. 1 As part of the device-layers generation, the contact locations forming the nets are generated. (A change has been performed on the gate contact locations generated by DRE such that the gate contacts are not all generated on the same horizontal level; instead, connected gates have contacts that are aligned at the same y-location for ease of routing, but unconnected gates can have their poly contacts at different y-locations.…”

Role of Design in Multiple Patterning: Technology Development, Design Enablement and Process Control

“…Technology developers then need to decide on which layout configurations to enable -by pushing the manufacturing process -and which ones to forbid in the design. To make such decision, a prediction of the design implications of forbidding/allowing each configuration is needed [1]- [3].…”

“…Designing with MP rules is believed to be a hassle and conservative rules are expected to have a significant cost in terms of area [18,19]. Additionally, in a previous work [1], we develop a framework for design rules evaluation, UCLA_DRE, and use it to evaluate the density impact of using conservative MP rules for standard-cell layout generation that would virtually eliminate any possibility of MP conflicts. The results are depicted in Figure 3.…”

Comprehensive die-level assessment of design rules and layouts

“…More recently, the work of [6] offers a framework for evaluating design rules, at early stages of technology development, through fast layouttopology generation of standard-cell layouts and estimation of variability and manufacturability using first-order models. This work has two major limitations.…”