0.18μm铜金属双重镶嵌工艺中空间成像套刻精度分析

由于空间成像套刻(Overlay)技术的预算随集成电路(IC)设计规范的紧缩而吃紧,因此,Overlay测量技术准确度的重要意义也随之提高。通过对后开发(AfterDevelopDI)阶段和后蚀刻(AfterEtchFI)阶段的Overlay测量结果进行比较,研究了0.18μm设计规范下的铜金属双重镶嵌工艺过程中的Overlay准确度。在确保对同一个晶圆进行后开发(DI)阶段和后蚀刻(FI)阶段测试的条件下,我们对成品晶圆的5个工艺层进行了比较。此外,还利用CD-SEM(线宽-扫描电子显微镜)测量了某个工艺层(PolyGate)上的芯片内Overlay,并与采用分割线方法的光学Overlay测量结果进行了比较。发现对芯片内overlay的校准存在着严重的局限性,即在应用CD-SEM时缺乏合适的结构进行Overlay测量。我们还将继续为大家提供定量的比较结果,同时也会向大家推荐组合的CD-SEM测量结构,使其能够被应用到今后的光刻设计中。     

Cleaning UF membranes with simple and formulated solutions

The ultrafiltration membranes fouled by proteins are typically cleaned by consecutive soaking in alkali, surfactant and oxidizing solutions. We combined all three chemicals into a formulated cleaning agent and examined its efficiency to restore the water flux without damaging the membrane or enhancing protein fouling. Lower concentrations of ingredients in the composite were required to restore the water flux to the initial level. The membrane after the cleaning remained intact and subsequent filtration left trace protein amount on the membrane surface. We propose a mechanism of cleaning based on a fast penetration of alkali and oxidizing ingredients through a fouling layer and efficient micellation of detached foulants with surfactant.     

Prediction of the delayed neutron yields for actinide nuclides

Prediction of delayed neutron yields for actinides which are important in the nuclear energy field is given. The prediction is based on a correlation related to a suggested cluster structure of the nucleus.     

Minimization of matrices in the inverse perturbation method

A derivative of a functional with respect to matrices is defined. This definition is useful as a vehicle for obtaining a matrix that possesses a minimal norm. This minimization is required for determining the ‘generalized bias operator’. The latter is used in calculations aimed at improving the agreement between the calculated and measured parameters of physical systems.     

Lower Bounds on the Query Complexity of Non-uniform and Adaptive Reductions Showing Hardness Amplification

Hardness amplification results show that for every Boolean function f, there exists a Boolean function Amp(f) such that if every size s circuit computes f correctly on at most a 1 ? δ fraction of inputs, then every size s′ circuit computes Amp(f) correctly on at most a ${1/2+\epsilon}$ fraction of inputs. All hardness amplification results in the literature suffer from “size loss” meaning that ${s' \leq \epsilon \cdot s}$ . We show that proofs using “non-uniform reductions” must suffer from such size loss. A reduction is an oracle circuit ${R^{(\cdot)}}$ which given oracle access to any function D that computes Amp(f) correctly on a ${1/2+\epsilon}$ fraction of inputs, computes f correctly on a 1 ? δ fraction of inputs. A non-uniform reduction is allowed to also receive a short advice string that may depend on both f and D. The well-known connection between hardness amplification and list-decodable error-correcting codes implies that reductions showing hardness amplification cannot be uniform for ${\epsilon < 1/4}$ . We show that every non-uniform reduction must make at least ${\Omega(1/\epsilon)}$ queries to its oracle, which implies size loss. Our result is the first lower bound that applies to non-uniform reductions that are adaptive, whereas previous bounds by Shaltiel & Viola (SICOMP 2010) applied only to non-adaptive reductions. We also prove similar bounds for a stronger notion of “function-specific” reductions in which the reduction is only required to work for a specific function f.     

Practical Thermal Multi–Scale Analysis for Composite Materials–Mechanical-Orientated Approach

This paper describes a thermal multi-scale formulation for composite materials based on a mechanical homogenization approach. The presented formulation evaluates the effective macroscopic thermal conductivity of the composite materials and also the microscopic heat flux field by scaling down to the micro-scale level. The effective thermal conductivity of the composite materials was calculated by applying the homogenization theory over the unit cell. The uniqueness of the presented multi-scale analysis related to the elastic problems solved at the microscopic scale (unit cell). This method has the advantage of applying periodic boundary conditions and uniform macroscopic temperature gradient over the unit cell. The proposed thermal multi-scale analysis was verified and its efficiency was demonstrated on large scale problem.     

Coming challenges in microarchitecture and architecture

In the past several decades, the world of computers and especially that of microprocessors has witnessed phenomenal advances. Computers have exhibited ever-increasing performance and decreasing costs, making them more affordable and in turn, accelerating additional software and hardware development that fueled this process even more. The technology that enabled this exponential growth is a combination of advancements in process technology, microarchitecture, architecture, and design and development tools. While the pace of this progress has been quite impressive over the last two decades, it has become harder and harder to keep up this pace. New process technology requires more expensive megafabs and new performance levels require larger die, higher power consumption, and enormous design and validation effort. Furthermore, as CMOS technology continues to advance, microprocessor design is exposed to a new set of challenges. In the near future, microarchitecture has to consider and explicitly manage the limits of semiconductor technology, such as wire delays, power dissipation, and soft errors. In this paper we describe the role of microarchitecture in the computer world present the challenges ahead of us, and highlight areas where microarchitecture can help address these challenges     

Production outsourcing: A linear programming model for the Theory-Of-Constraints

This paper presents an analysis of the outsourcing problem. Pertinent variables are identified and the relationships between them are defined. We formulate the outsourcing problem as a Linear-Programming (LP) problem and identify an analytical solution. We proceed with an example examining three decision models: standard cost accounting, standard Theory-Of-Constraints (TOC) and our own solution. The model enables managers to determine which products to manufacture and which to outsource. The solution of the LP formulation enables managers to apply the model by computing an operational ratio, without having to solve a linear programming problem. The final model is simpler to apply and requires the computation of fewer variables than other prevalent models.     

Local versus Global in Quasi-Conformal Mapping for Medical Imaging

A method and algorithm of flattening folded surfaces, for two-dimensional representation and analysis of medical images, are presented. The method is based on an application to triangular meshes of classical results of Gehring and Väisälä regarding the existence of quasi-conformal and quasi-isometric mappings.The proposed algorithm is basically local and, therefore, suitable for extensively folded surfaces encountered in medical imaging. The theory and algorithm guarantee minimal distance, angle and area distortion. Yet, the algorithm is relatively simple, robust and computationally efficient, since it does not require computational derivatives. Both random-starting-point and curvature-based versions of the algorithm are presented.We demonstrate the algorithm using medical data obtained from real CT images of the colon and MRI scans of the human cortex. Further applications of the algorithm, for image processing in general are also considered. The globality of this algorithm is also studied, via extreme length methods for which we develop a technique of computing straightest geodesics on polyhedral surfaces.