Systems, methods and mediums are provided for dynamic adjustment of sampling plans in connection with a wafer (or other device) to be measured. The invention adjusts the frequency and/or spatial resolution of measurements on an as-needed basis when one or more events occur that are likely to indicate an internal or external change affecting the manufacturing process or results. The dynamic metrology plan adjusts the spatial resolution of sampling within-wafer by adding, subtracting or replacing candidate points from the sampling plan, in response to certain events which suggest that additional or different measurements of the wafer may be desirable. Further, the invention may be used in connection with adjusting the frequency of wafer-to-wafer measurements.

Dynamic metrology schemes and sampling schemes for advanced process control in semiconductor processing

The advances in Industry 4.0 provide both challenges and opportunities for digital manufacturing and assembly systems. This paper first addresses the state-of-the-art readiness for Industry 4.0 concerning assembly and manufacturing systems through a literature review of the relevant papers recently published. Then it assesses the challenges faced nowadays by assembly and manufacturing systems. Third, it focuses on the most promising future developments and evolution of such production systems as well as their digitalisation. Finally, this manuscript illustrates the content of the papers selected for this special issue. Through the study presented in this special issue, valuable contributions to both theory and application in this area have been achieved, and a useful reference for future research is given.

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Design and management of digital manufacturing and assembly systems in the Industry 4.0 era

Generic interface adapter builder software generates an interface adapter to tie tools into a centralized manufacturing execution system. As contemplated by embodiments of the present invention, the interface adapter allows a tool in a semiconductor manufacturing assembly to communicate with other hardware and software in the centralized manufacturing execution system in accordance with a standard protocol and be operable from a common view graphical user interface. The generic interface builder software uses a classification of the type library and desired parameters for a particular tool to generate the interface adapter that maps the interface methods of the tool to the interface of the manufacturing execution system and handles long running service request support. In one aspect of the invention, the tool to be integrated into the manufacturing assembly may be a material control system. As contemplated by embodiments of the present invention, the material control system uses COM-based interface methods, and may optionally include a COM-based protocol converter, and may expose its interface methods via a type library.

Generic interface builder

A method of controlling surface non-uniformity of a wafer in a polishing operation includes (a) providing a model for a wafer polishing that defines a plurality of regions on a wafer and identifies a wafer material removal rate in a polishing step of a polishing process for each of the regions, wherein the polishing process comprises a plurality of polishing steps, (b) polishing a wafer using a first polishing recipe based upon an incoming wafer thickness profile, (c) determining a wafer thickness profile for the post-polished wafer of step (b), and (d) calculating an updated polishing recipe based upon the wafer thickness profile of step (c) and the model of step (a) to maintain a target wafer thickness profile. The model can information about the tool state to improve the model quality. The method can be used to provide feedback to a plurality of platen stations.

Feedback control of a chemical mechanical polishing device providing manipulation of removal rate profiles

A method, apparatus and medium of conditioning a planarizing surface includes installing a wafer to be polished in a chemical mechanical polishing (CMP) apparatus having a polishing pad and a conditioning disk, polishing the wafer under a first set of pad conditioning parameters selected to maintain wafer material removal rates with preselected minimum and maximum removal rates, determining a wafer material removal rate occurring during the polishing step, calculating updated pad conditioning parameters to maintain wafer material removal rates within the maximum and minimum removal rates, and conditioning the polishing pad using the updated pad conditioning parameters, wherein the updated pad conditioning parameters are calculated by a pad wear and conditioning model that predicts the wafer material removal rate of the polishing pad based upon the rotational speed and direction of the conditioning disk.

Control of chemical mechanical polishing pad conditioner directional velocity to improve pad life

Increasing fab construction costs, shortening product life cycles, and eroding market prices have become critical realities for today's semiconductor manufacturers. Consequently, many semiconductor facilities are now facing increasing pressure to quickly reach and maintain profitability by achieving faster yield ramps and sustaining higher product yields, while concurrently keeping the operational costs to a minimum. Inherently, these goals are in constant conflict, and the problem of optimally allocating various types of defect inspection equipment in an advanced semiconductor manufacturing line can be complex. The optimal sampling requirements are also dynamic, and are dependent upon the process technology, the product operational phase, and the business environment.

Optimized sample planning for wafer defect inspection

The fabless-foundry partnership for integrated circuit (IC) manufacturing business is expected to grow from 12% in 1995 to approximately 17% (i.e., $45B) of the total IC market in 2000. The growth of this market will be even more significant for subquarter micron technologies-whose growth is driven by the multimedia industry. The customer base will extend beyond traditional fabless IC companies into vertically integrated IC manufacturers and system vendors. Given the rate of growth and the high technology profile of products, substantial investments in capital, technology, and skilled workforce have to be dedicated and managed effectively for ensuring a successful partnership. In this paper, we outline the potential coordination problems that may arise in such partnerships, and propose a framework for analyzing issues related to yield information sharing and yield improvement. Our analysis indicates that fabless-foundry contracts that are based on a fixed number of good dies, and better yield information are more profitable.

Fabless-foundry partnership: models and analysis of coordination issues

We study a programmable robotic part feeder that relies on a sequence of three conveyor belts to singulate and re‐circulate parts In industrial practice, belt speeds are set in an ad hoc fashion Experience with real feeders reveals that throughput can suffer owing to: starvation where no parts are visible to the camera; and saturation, where too many parts are visible, which prevents identifying part pose or grasping due to obstruction by nearby parts This motivates our search for a systematic approach to setting belt speeds Our goal is to optimize throughput, measured in terms of how many parts per second are delivered from the robotic feeder We describe a 1D model of the belts with a Poisson arrival process to stochastically model how belt speeds affect throughput Initially, we study the finite case where N parts are placed into the feeder and re‐circulated until they are all delivered by the robot Our first insight is that the vision belt should be run at maximum achievable velocity We run simulations to empirically determine optimal buffer belt velocity as a function of lot size Finally, we develop a theoretical model for the case where N = ∞ which approximates common usage where the buffer is replenished before it becomes empty From this model, we derive the optimal buffer belt velocity and show that it produces throughput five times greater than that achieved with ad hoc settings

Tuning robotic part feeder parameters to maximize throughput

Critical dimension (CD) control in lithography and etch processing is imperative in order to achieve optimum device yield and speed performance for semiconductor manufacturing As linewidths are reduced, the sources of CD errors do not automatically scale, and the detection of process excursions becomes more critical An optimized CD measurement sampling plan can ensure an economical baseline control and the effective detection of process excursions In this paper, we discuss the strengths and weaknesses of existing measurement sampling, analysis, and control techniques in their ability to identify certain CD process exclusions We present a comprehensive methodology to characterize the process baseline variations and process excursions Sampling plan choices ape evaluated and based on the balance between leaving material at risk (beta error) and generating false alarms (alpha risk) With the availability of specific fab data such as wafer starts and die selling price, the sample planning model can be used to evaluate costs and risk of alternate sampling plans Specific fab cost data also allows for the calculation of the cost optimal sampling plan for a given inspection capacity

Critical dimension sample planning for sub-0.25 micron processes

Purpose – This paper aims to study a commercially available industrial part feeder that uses an industrial robot arm and computer vision system. Three conveyor belts are arranged to singulate and circulate parts, bringing them under a camera where their pose is recognized and subsequently manipulated by the robot arm. The problem is addressed of optimizing belt speeds and hence throughput of this feeder that avoid: starvation, where no parts are visible to the camera and saturation, where too many parts prevent part pose detection or grasping.Design/methodology/approach – Models are developed for intermittent and continuous motion feeding based on a 2D Poisson process. Renewal theory is applied to model intermittent motion and an M/G/1 queue with customer impatience to model continuous motion feeding. These models are verified using discrete event simulation.Findings – The models predict and optimize feeder behaviour very accurately and it is possible to compute optimal settings for different part sizes a...

D. Gudmundsson

Papers

Optimized sample planning for wafer defect inspection

Fabless-foundry partnership: models and analysis of coordination issues

Tuning robotic part feeder parameters to maximize throughput

Critical dimension sample planning for sub-0.25 micron processes

Optimizing robotic part feeder throughput with queueing theory