Journal of Microlithography, Microfabrication, and Microsystems

Inverse lithography for 45-nm-node contact holes at 1.35 numerical aperture

Monica Laurel Kempsell, Eric Hendrickx, Alexander Tritchkov et al.
Inverse lithography technology (ILT) is a procedure that optimizes the mask layout to produce an image at the wafer with the targeted aerial image. For an illumination condition optimized for dense pitches, ILT inserts model-based subresolution assist features (AF) to improve the imaging of isolated ... [J. Micro/Nanolith. MEMS MOEMS 8, 043001 (2009)] published Wed Nov 18, 2009.

Fabrication of silicon microring resonator with smooth sidewalls

Yao Chen, Junbo Feng, Zhiping Zhou et al.
Fabrication of silicon microring resonators was optimized by using electron-beam lithography (EBL) and inductively coupled plasma (ICP) etching with different mask materials. Sidewall roughness of less than 10 nm was revealed by high-resolution scanning electron microscopy (SEM) without any post-et ... [J. Micro/Nanolith. MEMS MOEMS 8, 043060 (2009)] published Fri Nov 13, 2009.

Predicting distortions and overlay errors due to wafer deformation during chucking on lithography scanners

Kevin T. Turner, Sathish Veeraraghavan, and Jaydeep K. Sinha
Chucking of substrates with wafer shape and thickness variations results in elastic deformation that can cause significant in-plane distortions that lead to overlay errors in lithographic patterning. As feature sizes shrink, overlay errors due to the combination of wafer geometry and chucking become ... [J. Micro/Nanolith. MEMS MOEMS 8, 043015 (2009)] published Fri Nov 6, 2009.

Nonionic photoacid generator behavior under high-energy exposure sources

Richard A. Lawson, David E. Noga, Laren M. Tolbert et al.
A series of nonionic photoacid generators (PAGs) are synthesized and their acid generation efficiency measured under deep ultraviolet (DUV) and electron beam exposures. The acid generation efficiency is determined with an on-wafer method that uses spectroscopic ellipsometry to measure the absorbance ... [J. Micro/Nanolith. MEMS MOEMS 8, 043010 (2009)] published Fri Nov 6, 2009.

Analysis of Coulomb and Johnsen-Rahbek electrostatic chuck performance in the presence of particles for extreme ultraviolet lithography

Michael R. Sogard, Andrew R. Mikkelson, Vasu Ramaswamy et al.
The successful implementation of extreme ultraviolet lithography (EUVL) requires the use of an electrostatic chuck to both support and flatten the mask during scanning exposure. The EUVL Mask Standard, SEMI P37, specifies the nonflatness of the mask frontside and backside, as well as the thickness v ... [J. Micro/Nanolith. MEMS MOEMS 8, 041506 (2009)] published Mon Nov 2, 2009.

Gap regulation for suspended rotating disk used for microgyroscopes

Nan-Chyuan Tsai, Bing-Hong Liou, and Chih-Che Lin
An innovative magnetic module that is concurrently capable of performing as an actuator and a sensor is proposed and analyzed. The magnetic module is basically similar to a microscale linear variable differential transformer (LVDT), which is employed to actively adjust the height of a rotating seism ... [J. Micro/Nanolith. MEMS MOEMS 8, 043045 (2009)] published Thu Oct 29, 2009.

Novel approach for microassembly of three-dimensional rotary MOEMS mirrors

Lidai Wang, James K. Mills, and William L. Cleghorn
We present a novel approach to construct 3-D 1 x N rotary micromirrors, which are fundamental components in optical switching systems. A rotary micromirror consists of two microparts: a rotary micromotor and a micromirror. Both of the two microparts are fabricated with PolyMUMPs, (MEMSCAP, Research ... [J. Micro/Nanolith. MEMS MOEMS 8, 043035 (2009)] published Thu Oct 29, 2009.

Feedback-stabilized deformable membrane mirrors for focus control

Sarah J. Lukes, Phillip A. Himmer, Eric J. Moog et al.
This paper describes a method to extend the range of motion of a deformable, continuous membrane mirror beyond the limit of open-loop electrostatic instability through feedback control. The feedback scheme employs capacitive sensing directly at the mirror actuation electrodes and is based on frequen ... [J. Micro/Nanolith. MEMS MOEMS 8, 043040 (2009)] published Tue Oct 27, 2009.

Effects of layers and vias on continuous-wave laser heating and damage of surface-micromachined structures

Justin R. Serrano and Leslie M. Phinney
The response of microsystem components to laser irradiation is relevant to processes and applications such as laser processing, optical diagnostics, and optical microelectromechanical systems (MEMS) device design and performance. The dimensions of MEMS, which are on the order of several micrometers, ... [J. Micro/Nanolith. MEMS MOEMS 8, 043030 (2009)] published Thu Oct 22, 2009.

Development progress of optics for extreme ultraviolet lithography at Nikon

Katsuhiko Murakami, Tetsuya Oshino, Hiroyuki Kondo et al.
The full-field extreme ultraviolet (EUV) exposure tool named EUV1 is integrated and exposure experiments are started with a numerical aperture of the projection optics of 0.25, and conventional partial coherent illumination with a coherence factor of 0.8. 32-nm elbow patterns are resolved in a full ... [J. Micro/Nanolith. MEMS MOEMS 8, 041507 (2009)] published Mon Oct 5, 2009.

Imaging budgets for extreme ultraviolet optics: ready for 22-nm node and beyond

Marc Bienert, Aksel Gohnemeier, Oliver Natt et al.
We derive an imaging budget from the performance of extreme ultraviolet (EUV) optics with NA = 0.32, and demonstrate that the requirements for 22-nm applications are met. Based on aerial image simulations, we analyze the impact of all relevant contributors, ranging from conventional quantities like ... [J. Micro/Nanolith. MEMS MOEMS 8, 041509 (2009)] published Mon Oct 5, 2009.

Flare in extreme ultraviolet lithography: metrology, out-of-band radiation, fractal point-spread function, and flare map calibration

Gian F. Lorusso, Frieda Van Roey, Eric Hendrickx et al.
The critical role of flare in extreme ultraviolet (EUV) lithography is well known. In this work, the implementation of a robust flare metrology is discussed, and the proposed approach is qualified both in terms of precision and accuracy. The flare measurements are compared to full-chip simulations u ... [J. Micro/Nanolith. MEMS MOEMS 8, 041505 (2009)] published Mon Oct 5, 2009.

Process liability evaluation for extreme ultraviolet lithography

Hajime Aoyama, Kazuo Tawarayama, Yuusuke Tanaka et al.
This work concerns the readiness of extreme ultraviolet lithography (EUVL) for high-volume manufacturing based on accelerated development in critical areas, and the construction of a process liability (PL) test site that integrates results in these areas. Overall lithography performance is determine ... [J. Micro/Nanolith. MEMS MOEMS 8, 041508 (2009)] published Mon Oct 5, 2009.

Performance results of laser-produced plasma test and prototype light sources for EUV lithography

Norbert R. Bowering, Igor V. Fomenkov, David C. Brandt et al.
Improved performance and specific results are reported for several test and prototype extreme ultraviolet (EUV) light sources developed for next-generation lithography. High repetition rate and high-power CO laser-produced plasma sources operating on tin droplet targets are described. Details of las ... [J. Micro/Nanolith. MEMS MOEMS 8, 041504 (2009)] published Mon Oct 5, 2009.

Study of the contour-based optical proximity correction methodology

Liang Zhu, Xiaohui Kang, Yili Gu et al.
As design rule continues to shrink, resolution enhancement techniques (RET) such as optical proximity correction (OPC) become more and more complex to enable design printability. As we know, typically integrated circuit (IC) layouts are simple shapes such as rectangles. However, high spatial frequen ... [J. Micro/Nanolith. MEMS MOEMS 8, 043005 (2009)] published Fri Oct 2, 2009.

In situ measurement of gas diffusion properties of polymeric seals used in MEMS packages by optical gas leak testing

Changsoo Jang, Arindam Goswami, Bongtae Han et al.
A novel inverse approach is proposed for in situ measurement of gas diffusion properties of polymeric seals used in microelectromechanical systems (MEMS) packages. The cavity pressure evolution of a polymer-sealed MEMS package subjected to a constant bombing pressure is documented as a function of t ... [J. Micro/Nanolith. MEMS MOEMS 8, 043025 (2009)] published Fri Oct 2, 2009.

Effects of plasma spatial profile on conversion efficiency of laser-produced plasma sources for EUV lithography

Ahmed Hassanein, Valeryi Sizyuk, Tatyana Sizyuk et al.
Extreme ultraviolet (EUV) lithography devices that use laser-produced plasma (LPP), discharge-produced plasma (DPP), and hybrid devices need to be optimized to achieve sufficient brightness with minimum debris generation to support the throughput requirements of high-volume manufacturing lithograph ... [J. Micro/Nanolith. MEMS MOEMS 8, 041503 (2009)] published Fri Oct 2, 2009.

Thick-membrane-operated radio frequency switches with wafer-level package using gold compressive bonding

Jongseok Kim, Sangwook Kwon, Youngtack Hong et al.
An electrostatically actuated radio frequency (rf) switch is fabricated using a thick silicon membrane, and the device is packaged using a high resistivity silicon cap wafer with a gold (Au) thermocompressive bonding method. To achieve an rf switch that can operate at low voltage, a thick membrane w ... [J. Micro/Nanolith. MEMS MOEMS 8, 043020 (2009)] published Fri Oct 2, 2009.

Estimating the out-of-band radiation flare levels for extreme ultraviolet lithography

Simi A. George, Patrick P. Naulleau, Senajith Rekawa et al.
For the commercialization of extreme ultraviolet lithography (EUVL), discharge or laser-produced, pulsed plasma light sources are being considered. These sources are known to emit into a broad range of wavelengths that are collectively referred to as out-of-band (OOB) radiation by lithographers. Mul ... [J. Micro/Nanolith. MEMS MOEMS 8, 041502 (2009)] published Fri Oct 2, 2009.

How does a reviewer make a difference?

Burn J. Lin
Abstract not available. [J. Micro/Nanolith. MEMS MOEMS 8, 030101 (2009)] published Tue Sep 29, 2009.

Fluid-photoresist interactions and imaging in high-index immersion lithography

Hoang V. Tran, Eric Hendrickx, Frieda Van Roey et al.
Optical immersion lithography using fluids with refractive indices greater than that of water (1.436) can enable numerical apertures of 1.55 or above for printing sub-45-nm lines. Two second-generation immersion fluid candidates, IF132 and IF169, both have indices above 1.64 and have been optimized ... [J. Micro/Nanolith. MEMS MOEMS 8, 033006 (2009)] published Wed Sep 23, 2009.

Hotspot management and its applications in ultralow k lithography

Kohji Hashimoto, Satoshi Usui, Shigeki Nojima et al.
We have constructed a hotspot management flow and applied the flow to large-scale integration (LSI) manufacturing in the ultralow k lithography era. This flow involves three main management steps: hotspot reduction, hotspot extraction, and hotspot monitoring. Hotspot reduction works with lithography ... [J. Micro/Nanolith. MEMS MOEMS 8, 033007 (2009)] published Mon Sep 21, 2009.

Calibration of physical resist models: methods, usability, and predictive power

Ulrich Klostermann, Thomas Mulders, Denis Ponomarenco et al.
We discuss the methodology of physical resist model calibration for a rigorous lithography simulator under various aspects and assess the resulting predictive accuracy. The study is performed on an extensive optical proximity correction (OPC) dataset, which includes several thousands of critical dim ... [J. Micro/Nanolith. MEMS MOEMS 8, 033005 (2009)] published Fri Sep 18, 2009.

Guest Editorial: Computational Lithography

Donis Flagello and Chris Mack
Abstract not available. [J. Micro/Nanolith. MEMS MOEMS 8, 031401 (2009)] published Fri Sep 18, 2009.

Guest Editorial: Reliability, Packaging, Testing, and Characterization of MEMS and MOEMS

Rajeshuni Ramesham and Allyson L. Hartzell
Abstract not available. [J. Micro/Nanolith. MEMS MOEMS 8, 031301 (2009)] published Wed Sep 16, 2009.

Mechanical characterization and insertion performance of hollow microneedle array for cell surgery

Takahiro Kawashima, Takahiro Sakai, Norihisa Kato et al.
In order to implement cell surgery on a chip-based system, we have been developing microneedle arrays capable of introducing desired biomolecules (nucleic acids, proteins, etc.) into living cells and the parallel extracting biomolecules expressed in the cells. An array of hollow silicon dioxide (SiO ... [J. Micro/Nanolith. MEMS MOEMS 8, 033014 (2009)] published Tue Sep 15, 2009.

Patterning of multilayer dielectric optical filters using metal masks fabricated by electroforming and photolithography

Cheng-Chung Jaing, Chii-Rong Yang, Chun-Ming Chang et al.
Ni films, replacing photoresists, serve as masks in the selective deposition of optical thin films by electron-beam gun evaporation at a substrate temperature of 300 degrees C. Photolithography is adopted herein to define the growth of Ni films by electroforming. Mosaic patterns with a width of 20 ... [J. Micro/Nanolith. MEMS MOEMS 8, 033009 (2009)] published Thu Sep 10, 2009.

Novel optical sensor based on morphology-dependent resonances for measuring thermal deformation in microelectromechanical systems devices

Anisur Rahman, Reginald Eze, and Sunil Kumar
We have reported a novel optical sensor based on whispering gallery mode (WGM) resonance for measuring thermal deformation in microelectromechanical systems (MEMS) devices. New asymptotic expressions for transverse electric and transverse magnetic waves are developed based on electromagnetic theory ... [J. Micro/Nanolith. MEMS MOEMS 8, 033071 (2009)] published Wed Sep 9, 2009.

Critical study of high-sensitivity pressure sensors with silicon/porous silicon composite membranes

L. Sujatha, Vishwas S. Kale, and Enakshi Bhattacharya
Since porous silicon (PS) has a much lower Young's modulus than single crystalline silicon, Si/PS composite membranes deflect more and can be used to fabricate pressure sensors with improved sensitivity. However, PS has some drawbacks, like weaker structural stability and being more susceptible to h ... [J. Micro/Nanolith. MEMS MOEMS 8, 033070 (2009)] published Thu Sep 3, 2009.

Analyses of whispering-gallery modes in small resonators

Haiyong Quan and Zhixiong Guo
Whispering-gallery (WG) modes in photonic microdevices made of dielectric circularly planar resonators are analyzed. The wave equation is solved by using the method of separation of variables based on the eigenvalue technique. The resonant frequency at an azimuthal mode is decided by iteration using ... [J. Micro/Nanolith. MEMS MOEMS 8, 033060 (2009)] published Fri Aug 28, 2009.

Optimal approximation of transfer cross coefficient for system transmission based on tensorial signal methods

Romuald Sabatier, Caroline Fossati, Salah Bourennane et al.
In photolithography, aerial image simulation of the mask has become mandatory. To compute aerial images, transmission cross coefficients (TCCs), drawn from Hopkins optical system transmission function, are arranged as a four-way array (four-entry table) called a fourth-order tensor. To estimate the ... [J. Micro/Nanolith. MEMS MOEMS 8, 031407 (2009)] published Fri Aug 28, 2009.

Aerial image back propagation with two-dimensional transmission cross coefficient

Kenji Yamazoe, Yoshiyuki Sekine, and Tokuyuki Honda
We present the basic concept of a fast mask optimization method that utilizes target-intensity back propagation. This method decomposes the target-intensity using a two-dimensional (2-D) transmission cross coefficient. After applying normal incidence approximation to the decomposed target intensity, ... [J. Micro/Nanolith. MEMS MOEMS 8, 031406 (2009)] published Tue Aug 25, 2009.