As optical lithography advances into the 65nm technology node and beyond, minimum feature size outpaces the lithography wavelength. As a result, mask/wafer manufacturing yield improvement and cost reduction have been widely accepted as key factors for aggressive technology scaling. This thesis is concerned with the following four manufacturability/manufacturing problems. Fracturing: Mask manufacturing for the 90nm and 65nm nodes increasingly deploys variable shaped beam mask writing machines. The pervasive use of OPC leads to dramatic increase in the number of thin trapezoids, which significantly decrease the mask manufacturing yield. This thesis suggests an optimal integer linear programming based fracturing approach and a fast heuristics which substantially reduce sliver count in comparison to leading commercial fracturing tools. MPW: Multiple project wafers (MPW) provide an attractive mask manufacturing cost reduction solution for low-volume production designs by sharing the cost of mask tooling among up to tens of designs. This thesis proposes a comprehensive MPW flow aimed at minimizing the manufacturing cost which includes (1) multi-project reticle floorplanning, and (2) wafer shot-map and dicing plan definition. PSM: In the context of wafer manufacturing, Alternating-Aperture Phase Shift Masking (AAPSM) will be used to image critical features on the polysilicon layer at smaller technology nodes. This technology imposes additional constraints on the layouts beyond traditional design rules. Phase conflicts have to be detected and removed to enable the use of AAPSM. This thesis has two key contributions: (1) a new computationally efficient approach to detect a minimal set of phase conflicts, which when corrected will produce a phase-assignable layout; (2) a novel layout modification scheme for correcting these phase conflicts in standard- cell blocks. Redundant Vias: Finally, a large part of wafer manufacturing yield loss is due to via voids, which can be relieved by redundant vias insertion or via doubling. This thesis proposes perfect matching based post -route via doubling which achieves optimum yield improvement. Redundant interconnects or "short loops& quot; are introduced to maximize the number of doubled vias. Experimental results show that near 100% via doubling coverage can be achieved with simultaneously optimal redundant via and short loop insertion in the post -route stage

Most Chinese words are compounds formed through the combination of meaningful characters. Yet, due to compositional complexity, it is poorly understood how this combinatorial process affects the access to the whole-word meaning. In the present study, we turned to the recent development in compositional distributional semantics (Marelli et al., 2017), and employed a deep neural network to learn the less-than-systematic relationship between the constituent characters and the compound words. Based on the compositional representations derived from the computational model, we quantified compositionality as the degree of overlap between the compositional and the lexicalized representations as well as the degree of distinctness of the compositional representation. We observed that these two compositional attributes can affect compound recognition over and above the effects of constituent character features and compound features. Moreover, we found that this effect was increasingly stronger when holistic access to the compound meaning became more challenging. These findings therefore, from a computational perspective, provided new evidence for the combinatorial process involved in Chinese word recognition, which also shed light on the universal process of compound comprehension.

We study signal integrity effects on statistical timing analysis, e.g., interconnect and gate delay variations induced by crosstalk aggressor alignment, i.e., difference in signal arrival times in coupled neighboring interconnects. Such effects bring significant source of variation, and must be taken into account in statistical timing analysis. We establish a functional relationship between signal propagation delay and crosstalk alignment by deterministic circuit simulation, and derive closed form formulas for statistical distributions of output signal arrival times. Our proposed method can be smoothly integrated into a static timing analyzer, which runtime is dominated by sampling deterministic delay calculation, while probabilistic computation and updating take constant time. Our experimental results on 70nm technology global interconnect structures and 130nm technology industry designs show that lack of statistical crosstalk alignment consideration could lead to up to 114.65% (71.26%) differences in interconnect delay means (standard deviations), and 159.4% (147.4%) differences in gate delay means (standard deviations), while our method gives within 1.28% (3.38%) mismatch in interconnect output signal arrival time means (standard deviations), and within 2.57% (3.86%) mismatch in gate output signal arrival time means (standard deviations), respectively.

Pre-2018 CSE ID: CS2007-0883

The aggressive scaling of VLSI feature size and the pervasive use of advanced reticle enhancement technologies leads to dramatic increases in mask costs, pushing prototype and low volume production designs at the limit of economic feasibility. Multiple project wafers (MPW), or "shuttle" runs, provide an attractive solution for such designs, by providing a mechanism to share the cost of mask tooling among up to tens of designs. However, MPW reticle floorplanning and wafer dicing introduce complexities not encountered in typical, single-project wafers. Recent works attempting to address these challenges have several drawbacks, including (i) assuming equal production volume requirement for all designs, (ii) assuming that the same dicing plan in used for all wafers or for all rows/columns of reticle images on a wafer, (iii) assuming unrealistic wafer models such as a rectangular array of projections, and (iv) disregarding important practical constraints on the maximum reticle size. In this report we propose a comprehensive MPW flow aimed at minimizing the number of wafers needed to fulfill given die production volumes. Our flow includes three main steps: (1)multi-project reticle floorplanning, (2) wafer shot-map definition, and (3) wafer dicing plan definition. For each of these steps we propose improved algorithms as follows. Our reticle floorplanner uses hierarchical quadrisection combined with simulated annealing to generate ``diceable'' floorplans observing given maximum reticle sizes. The new wafer shot-map definition step allows to fully utilize round wafer real estate by extracting the maximum number of functional dies from both fully and partially printed reticle images. Finally, our dicing planner allows multiple side-to-side dicing plans for different wafers as well as different reticle projection rows/columns within a wafer, and further improves dicing yield by partitioning each wafer into a small number of parts before individual die extraction. Experiments on industry testcases show that our methods outperform significantly not only previous methods in the literature, but also reticle floorplans manually designed by experienced engineers.

Pre-2018 CSE ID: CS2005-0823

For optimal water and fertilizer management under furrow irrigation, it is important to understand the water and solute dynamics on the land surface and in the subsurface. An efficient mathematical tool is required to describe these dynamic processes. We propose a coupled model in which surface water flow and solute transport are described using the zero-inertia equation and the average cross-sectional convection-dispersion equation, respectively, while the two-dimensional Richards equation and the convection-dispersion equation are used to simulate water flow and solute transport in soils, respectively. Solutions are computed numerically using finite differences for surface water flow and finite volumes for solute transports in furrow. Subsurface water flow and solute transport equations are solved using the CHAIN_2D code. An iterative method is used to couple computations of surface and subsurface processes. Both surface and subsurface water flow and solute transport modules are coded in program subroutines and functions in the Intel FORTRAN environment. The coupled model was validated by comparing its simulation results with measured data. Results showed that simulated water front advances in the furrow and water contents in the soil agreed with the observations reasonably well. Good simulations can be achieved with a relatively fine temporal resolution. Numerical oscillations can be eliminated by adopting appropriate time steps. As compared with the traditional furrow irrigation model, the proposed model can better quantify soil water and solute dynamics by considering interactions between surface and subsurface water flow and solute transport processes. The proposed model can be used as a decision tool to design and manage furrow irrigation.

Direct far-field visualization and characterization of surface plasmon polaritons (SPPs) are of great importance for fundamental studies and technological applications. To probe the evanescently confined plasmon fields, one usually requires advanced near-field techniques, which is typically not applicable for real-time, high-throughput detecting or mapping of SPPs in complicated environments. Here, we report the utilization of rare-earth-doped nanoparticles to quantitatively upconvert invisible, evanescently confined SPPs into visible photoluminescence emissions for direct far-field visualization of SPPs in a complicated environment. The observed interference fringes between the SPPs and the coherent incident light at the metal surface provide a quantitative measurement of the SPP wavelength and the SPP propagating length and the local dielectric environments. It thus creates a new signaling pathway to sensitively transduce the local dielectric environment change into interference periodicity variation, enabling a new design of directly measurable, spectrometer-free optical rulers for rapid, ultrasensitive label-free detection of various biomolecules, including streptavidin and prostate-specific antigen, down to the femtomolar level.

RATIONALE: Adjunct intra-arterial alteplase has been shown to potentially improve clinical outcomes in patients with large vessel occlusion (LVO) stroke who have undergone successful endovascular thrombectomy. Tenecteplase, known for its enhanced fibrin specificity and extended activity duration, could potentially enhance outcomes in stroke patients after successful reperfusion when used as an adjunct intra-arterial therapy. AIM: To explore the safety and efficacy of intra-arterial tenecteplase after successful endovascular thrombectomy in patients with LVO stroke. SAMPLE SIZE: To randomize 498 participants 1:1 to receive intra-arterial tenecteplase or no intra-arterial adjunctive thrombolysis therapy. METHODS AND DESIGN: An investigator-initiated, prospective, randomized, open-label, blind-endpoint multicenter clinical trial. Eligible patients with anterior circulation LVO stroke presenting within 24 h from symptom onset (time last known well) and excellent to complete reperfusion (expanded Thrombolysis In Cerebral Infarction (eTICI) scale 2c-3) at endovascular thrombectomy are planned to be randomized. OUTCOMES: The primary outcome is freedom from disability (modified Rankin Scale, mRS, of 0-1) at 90 days. The primary safety outcomes are mortality through 90 days and symptomatic intracranial hemorrhage within 48 h. DISCUSSION: The POST-TNK trial will evaluate the efficacy and safety of intra-arterial tenecteplase in patients with LVO stroke and excellent to complete reperfusion.