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This chapter describes best practices for one of the most important decisions a fabless MEMS company will make: selecting a foundry partner for volume wafer manufacturing.

For every company embarking on commercialization of a new product, a crucial question will be, “How much is it going to cost to develop this technology into a product?” Investors and executives need foresight on how much budget might be consumed prior to the arrival of revenue. In this chapter, we describe a method for estimating MEMS product development costs.

MEMS prototype fabrication can be expensive and very time-consuming. In this chapter, we introduce some basic strategies to minimize the risk of failure and to maximize learning and data-gathering in every prototyping run.

A MEMS design and the process flow that creates it are inseparable. In this chapter, we describe some MEMS process integration strategies, and what decisions can be made along the way in order to enable a new process flow and mask set to have a high probability of success in the fab.

This chapter presents insights and tools for creating unit cost models for ongoing production (recurring cost). A unit cost model is essential to establish the viability of a future business that must profit from selling its MEMS product. Although this chapter focuses on unit cost models for MEMS devices, the content will also be applicable to modeling any wafer-manufactured product, such as semiconductor, photonic, or nanotechnology devices.

In this chapter, we provide details regarding the steps of technology transfer in the context of working with a MEMS wafer foundry. The best practices and guidelines we describe, however, also apply to transferring any component to a third-party volume manufacturing vendor, such as an OSAT (off-shore assembly and test).

The MEMS product is a system composed of more than just the MEMS device. The MEMS product also includes the package, electronics, software, and possibly other components. This chapter introduces the typical components of a MEMS product, their roles, the partitioning of functions among components of the system, and the possible levels of physical integration. We limit the discussion in this chapter to an overview of the function partitioning and do not discuss the very wide variety of possible physical implementations.

Manufacturing test benefits the MEMS product company in many ways, including continuous improvement of the product, its yields, and its unit cost. Achieving these goals requires significant investment in equipment and a dedicated team. This chapter discusses the opportunity and cost of manufacturing test and strategies to manage risks.

The MEMS device is only one part of the MEMS product that includes the package, the electronics, and potentially other components. The development of the package and the electronics can each take years, so serial development is not practical. This chapter discusses methods to codevelop the MEMS, package, and electronics in parallel.

Micro electromechanical systems, or MEMS, are a technology that encompasses an amazing variety of devices that enrich products in diverse applications such as consumer electronics, automobiles, medical devices, industrial equipment, spacecraft, and more. While that variety creates valuable product differentiation and business opportunities, it also stubbornly resists standardization, which poses a challenge to commercialization. This chapter motivates the strategies and best practices, described throughout this book, for enabling successful MEMS product development.

Understanding the infrastructure for semiconductor device manufacturing provides important context for MEMS development. However, MEMS devices differ from other semiconductor devices, and these differences impact MEMS device development. This chapter discusses the semiconductor device manufacturing infrastructure and highlights ways MEMS device manufacture is both similar and different.

Completed wafers from the foundry go through the back-end-of-line (BEOL) to become individually packaged and tested die. The back end process imposes requirements on the MEMS die design and wafer layout, which are best accommodated in the early development stages. This chapter describes BEOL activities and points out some of the requirements imposed on MEMS die design and wafer layout.

Transferring technology from a research and development facility to a volume production facility is a critical turning point in MEMS product commercialization. This chapter discusses the technical and business factors needed to determine your company’s readiness to make this important transition.

The MEMS field may be rapidly maturing, but there are still few shortcuts through the stages of MEMS product development. Whether you are launching a breakthrough product or a next-generation design of an existing product, your product must go through multiple stages of development to achieve commercialization. This chapter outlines the significance and the challenges of five stages of MEMS product development: proof-of-concept prototype, advanced prototypes, foundry feasibility, foundry pilot production, and foundry production. Understanding why you need these stages, when these stages occur, and what evaluation gates exist between stages can ease your company through the MEMS product development process and, most importantly, ensure you have enough resources to reach your final goal.

MEMS product development requires a team of people to supply necessary expertise and functional roles. The team will have both internal and external members, the latter including key service vendors and material suppliers. The team composition must evolve and enlarge to reflect the progressing needs of MEMS development. This chapter outlines the essential functional roles needed at different development stages, as well as for different company profiles, during MEMS product development.

This chapter describes how to begin the task of designing a MEMS device from scratch, an effort that will proceed in parallel with design of other key pieces of the MEMS product system, such as the package and electronics. We describe how to use analytical models to efficiently estimate the design space of a novel device and thereby assess feasibility in the context of practical manufacturing and operational limits. We also describe when and how to effectively deploy computational modeling, accounting for uncertainty in input values, in order to save time and cost during product development.

A critical turning point of product commercialization is transferring the product technology and prototype from the R&D facility where the advanced prototype development occurred to the manufacturing facilities (or team) for foundry production. The MEMS product technology must be documented thoroughly to make the transfer process as efficient as possible. In this chapter, we provide an overview of the minimum set of documentation needed for the transfer process and our best practices for effective documentation.

In this chapter, we describe business strategies for acquiring and using third-party intellectual property to accelerate the development of new MEMS products. Disclaimer: This chapter does not provide legal advice. Please consult with a qualified intellectual property attorney for appropriate legal advice.

Development test is part of the design-fabrication-test workflow loop to develop a new MEMS device. This chapter first defines and distinguishes different types of test, including development test, manufacturing test, and qualification test. The chapter then discusses identifying test requirements, establishing test capability, and strategies for failure analysis during development.

This paper introduces the design of a high fill-factor (>99%) micromirror array that consists of 1 mm 2 hexagonal mirrors, which are expected to each independently achieve continuous, closed-loop control of three degrees of freedom (DOFs)-tip, tilt, and piston-over large ranges (> ± 10° rotation and > ± 30μm translation) at high speeds (~45 kHz for a 1° amplitude of rotational oscillation). The flexure topology of this array is designed using the freedom, actuation, and constraint topologies synthesis approach, which utilizes geometric shapes to help designers rapidly consider every flexure topology that best achieves a desired set of DOFs driven by decoupled actuators. The geometry of this array's comb-drive actuators is optimized in conjunction with the geometry of the system's flexures using a novel approach. The analytical models underlying this approach are verified using finite-element analysis and validated using experimental data. The capabilities of this new mirror array will enable, or significantly improve, the performance of a variety of high-impact optical technologies such as advanced optical switches, spatial-light modulators, displays, and laser steering or scanning devices.

We describe and validate a new failure prediction methodology specifically designed for single-crystal microelectromechanical systems (MEMS) devices under general service loadings. The methodology uses experimental data efficiently generated from fracture testing of simple test specimens to calculate a series of Weibull parameters descriptive of specific surface conditions. These data, combined with finite element modeling, are used to predict the fracture probability for any MEMS device fabricated by the same processes under any type of loading. We demonstrate the accuracy of our method by comparing predicted fracture probabilities against actual fracture test results for a micromirror in two distinct multiaxial loading configurations.

In the above paper [1] , there was an error in the first footnote regarding author contribution. The corrected author contribution information is as follows: (Jonathan B. Hopkins and Robert M. Panas are co-first authors.)

A 1296-port MEMS transparent optical crossconnect with 5.1dB/spl plusmn/1.1dB insertion loss at 1550 nm is reported. Measured worst-case optical crosstalk in a fabric was n38 dB and nominal switching rise/fall times were 5 ms. A 2.07 petabit/s switch capacity was verified upon cross-connecting a forty-channel by 40 Gb/s DWDM data stream through a prototype fabric.

Optical Micro-Electro-Mechanical Systems (Optical MEMS, or MOEMS) comprise a disruptive technology whose application to telecommunications networks is transforming the horizon for lightwave systems. The influences of materials systems, processing subtleties, and reliability requirements on design flexibility, functionality and commercialization of MOEMS are complex. A tight inter-dependent feedback loop between Component/ Subsystem/ System Design, Fabrication, Packaging, Manufacturing and Reliability is described as a strategy for building reliability into emerging MOEMS products while accelerating their development into commercial offerings.

We present a study of the anodic oxidation of MEMS poly-Silicon electrodes and wires in ambients with high relative humidity and high voltages. MEMS poly-Si electrodes that are hermetically packaged in dry ambients show no signs of degradation on a time scale of years even when operated at hundreds of volts. To accelerate electrical failure modes, we expose unpackaged chips to ambients with high relative humidity. We then observe anodic oxidation of the most positively biased poly-Si structures on a time scale of minutes or hours. We describe this anodic oxidation as a function of relative humidity and voltage, and its dependence on surface leakage currents.

While considerable press has been given to characterization of mechanical properties of MicroElectroMechanical Systems (MEMS) as related to reliability, environmental robustness, and lifetimes studies, characterization of electrical properties of MEMS have not been widely published. In this paper we present an examination of electrical properties (surface and substrate leakage currents, sheet resistance, substrate contact resistance and interlayer contact resistances) of polysilicon thin films used in surface micromachined MEMS test structures. Environmental and electrical overstress conditions that affect leakage have been studied. Two test structures have been used to independently study surface and substrate leakage currents at different levels of humidity (0% to 80% RH) and applied voltage (100 to 150 volts). Both static and lifetime studies have been conducted. Significant differences in surface and substrate leakage lifetime characteristics are observed, suggesting different failure mechanisms for these two important electrical phenomena in MEMS reliability.

We present a full factorial study of the effect of relative humidity and voltage on the oxidation of surface-micromachined poly-silicon wiring and electrodes. Our system consists of 500 nm thick poly-Si wires and electrodes insulated from the substrate wafer by 600 nm of Si-rch SixNy, fabricated using a surface-micromachinging process. In dry ambients, oxidation or damage to the bottom poly-Si layer (the Poly0 layer) in MicroElectroMechanical Systems (MEMS) devices occurs so slowly that little can be learned in a timely manner, even when stressing the electrodes at electric fields close to dielectric breakdown. We observe however that in ambient with elevated relative humidity the Poly0 wires and electrodes anodically oxidize within a short period of time when operated at moderately large voltages. Only the most positively biased poly-Si structures oxidize, and we describe the anodic oxidation and association volume expansion as a function of a number of accelerating factors including relative humidity and voltage. A threshold is observed in relative humidity bot not in voltage.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In the above titled paper (ibid., vol., 18, no. 4, pp. 962-970, Aug. 2009), there is a typographical error in equation (7). The correct equation is presented here.