International Business Machines Corporation

Other

Kabushiki Kaisha Toshiba

Emily E Fisch

Arne Watson Ballantine

Ronald A Warren

Gary L Milo

Scott Alan Estes

Hirofumi Inoue

Max Gerald Levy

Masami Aoki

Bruce Walter Porth

Harald F Okorn-Schmidt

James Allan Bruce

Orest Bula

William Alfred Syverson

Glenn Walton Gale

Louis M Kindt

Victor R Nastasi

James P Levin

Reginald R Bowley, Jr

Debra L Meunier

Paul C Buschner

Carey T Williams

Michael R Schmidt

In a process using a hot phosphoric acid etchant () to etch silicon nitride on a semiconductor wafer () submerged in a tank () of the etchant (), a recirculating path is established for the etchant (). A porous filter () is coated with silicon nitride and installed in the recirculating path. As the etchant () in the recirculating path flows through the porous filter (), the silicon nitride on the porous filter () dissolves into the etchant (). In the tank (), the silicon nitride dissolved in the etchant () significantly suppresses the etch of silicon dioxide on the semiconductor wafer (), thereby enhancing the etch selectivity of the process. Monitoring and maintaining the concentration of the silicon nitride in the etchant () stabilizes the etch selectivity of the process.

Etch apparatus

An extreme ultraviolet lithography (EUVL) mask structure and associated method of formation. A first conductive layer is provided between a buffer layer and an absorber layer such that the buffer layer is on a multilayer stack. The multilayer stack is adapted to substantially reflect EUV radiation incident thereon. The absorber layer is adapted to absorb essentially all of EUV radiation incident thereon. A mask pattern is formed in the absorber layer. Formation of the mask pattern in the absorber layer is accompanied by inadvertent formation of a defect in the absorber layer. The defect is subsequently repaired. The mask pattern may be extended into the first conductive layer and into the buffer layer in a substantially defect-free process that exposes a portion of the multilayer stack. A second conductive layer may be provided on the absorber layer, wherein the mask pattern is also formed in the second conductive layer.

EUVL mask structure and method of formation

In a process using a hot phosphoric acid etchant ( ) to etch silicon nitride on a semiconductor wafer ( ) submerged in a tank ( ) of the etchant ( ), a recirculating path is established for the etchant ( ). A porous filter ( ) is coated with silicon nitride and installed in the recirculating path. As the etchant ( ) in the recirculating path flows through the porous filter ( ), the silicon nitride on the porous filter ( ) dissolves into the etchant ( ). In the tank ( ), the silicon nitride dissolved in the etchant ( ) significantly suppresses the etch of silicon dioxide on the semiconductor wafer ( ), thereby enhancing the etch selectivity of the process. Monitoring and maintaining the concentration of the silicon nitride in the etchant ( ) stabilizes the etch selectivity of the process.

Etch process and apparatus therefor

A method and system for measuring lithographic image foreshortening. The method comprises the steps of providing a critical dimension scanning electron microscope, and using that critical dimension scanning electron microscope to measure lithographic image foreshortening. Preferably, a defined feature is formed using a lithographic process, and the critical dimension scanning electron microscope is used to measure foreshortening of that feature. For example, the feature may be a line, and the critical dimension scanning electron microscope may be used to measure foreshortening of the line. Also, the feature may be two arrays of lines, and the critical dimension scanning electron microscope may be used to measure the separation distance between the arrays. That separation distance may be used to determine a focus of the lithographic process.

Array foreshortening measurement using a critical dimension scanning electron microscope

A control target structure and method for monitoring the lithographic affects on minimum feature in a lithographic process. The control target uses line array elements having a nominal width. By changing the shape of the line-ends of the elements the control target can be optimized for controlling either focus or dose.

Structure for lithographic focus control features

A process for eliminating roughness on a silicon nitride trench liner is disclosed. A capping film on the top of the trench is formed in a self-aligned manner. This capping film prevents short circuits between a storage node and a passing word-line.

Self-aligned trench capacitor capping process for high density DRAM cells

A method for detecting physical interference with desired transport of an article. The method includes the step of detecting an operative acoustic signal representing the structure-borne sound pattern of an article during said article transport, and detecting the presence of interference based on the acoustic signal. A system for performing the method includes a transport device adapted to transport the article through a predetermined path and an acoustic sensor in structure-borne acoustic contact with the transport device and capable of producing an acoustic signal indicative of physical interference.

Structure and method for detection of physical interference during transport of an article

An array of ultrasonic or megasonic transducers is used to clean a substrate. An interference signal that is the superposition of the signals from each transducer enhances the cleaning. The system improves cleaning by providing a higher intensity beam than is available from uncoupled transducers to facilitate removal of smaller particles. In addition, the beam can be swept across the substrate to provide a uniform cleaning of the entire surface, avoiding dead spots. The system can be adapted for use in a vessel or for single wafer processing with a stream of fluid or a puddle of fluid.

Sonic cleaning with an interference signal

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Burlington, VT, United States of America

Emily E Fisch