Phase-shift mask

About: Phase-shift mask is a research topic. Over the lifetime, 2088 publications have been published within this topic receiving 18058 citations.

Improvement in metrology on new 3D-AFM platform

Abstract: According to the 2007 edition of the ITRS roadmap, the requireme nt for CD uniformity of isolated lines on a binary or attenuated phase shift mask is 2.1nm (3 1 ) in 2008 and requires improvement to1.3 nm (3 1 ) in 2010. In order to meet the increasing demand for CD uniformity on photo masks, improved CD metrology is required. A next generation AFM, InSight TM 3DAFM, has been developed to meet these increased requirements for advanced photo mask metrology. The new system achieves 2X improvement in CD and depth precision on advanced photo masks features over the previous generation 3D-AFM. This paper provides measurement data including depth, CD, and sidewall angle metrology. In addition the unique capabilities of damage-free defect inspection and Nanoimprint characterization by 3D AFM are presented. Keywords: Reference metrology, measurement uncertainty, critical dimension, 3D-AFM, photo mask, defect characterization, Nanoimprint 1. INTRODUCTION With the transition to the 32 nm node around the corner and the aggressive use of OPC to enhance resolution, feature sizes on photo masks will rapidly shrink below 100nm. This presents new challenges for defect characterization during mask inspection and repair. Furthermore, the requirements fo r critical dimension (CD) and depth measurements start to challenge traditional inspection methods with their inherent limitations such as material bias, proximity effects, as well as global and local charging. Effects such as line edge roughness that did not significantly contribute to the measured CD value above 100nm start to take up a significant amount of the total CD budget and need to be characterized. According to the 2007 edition of the ITRS roadmap the requirements for CD uniformity for isolated features on binary or attenuated phase shift masks is currently 2.1 nm (3 1 ) and will decrease to 1.3 nm (3 1 ) by 2010. In addition to these requirements the 2007 ITRS roadmap has replaced precision with a new quality me tric, measurement uncertainty (m. u.). Measurement uncertainty includes precision, but also accounts for additional errors due to tool matching, sampling uncertainty, and others making it a more stringent method to evaluate metrology performance. In this paper we introduce the InSight • 3D-AFM automated mask metrology platform and evaluate its performance as a dimensional reference metrology tool on chrome and resist features. We characterize baseline tool precision, measurement uncertainty on NIST-traceable metrology standards and precision on chrome and resist features. In addition we present small trench measurement capabilities on nano -imprinted resist structures and explorer its imaging capabilities for defect characterization.

Production of blank for halftone phase shift mask

Abstract: PURPOSE:To obtain a blank for halftone phase shift photomask which is usable for high-resolution lithography having transmittance sufficient to short- wavelength light. CONSTITUTION:This blank for halftone phase shift photomask is obtd. by forming the film of chromium evaporated or sputtered from metal chromium or chromium compd. in plasma formed from a fluorine atom-contg. gas on a transparent substrate 405, thereby forming at least one layer of layers consisting essentially of a chromium fluoride compd on the substrate.

Repair method for phase shift mask in semiconductor device

Abstract: The present invention is directed to prevent generating repair by-products during a repair process of a phase shift mask, and defects on a quartz substrate. According to the present invention, a repair method for phase shift mask in a semiconductor device so as to remove a bridge formed between a phase shift layer on a quartz substrate, comprises the steps of: first repairing the bridge by implanting a charging ion according to a focused ion beam(“FIB”) method; and second repairing the first repaired bridge portion by emitting laser and then removing the bridge.

Method for fabricating phase shift mask comprising the use of a second photoshield layer as a sidewall

Abstract: A method is provided for fabricating a phase shift mask of the out rigger sub-resolution type capable of accurately fabricating an ultra-fine semiconductor circuit. The method includes the steps of depositing a first photoshield metal layer and a first phase shift material layer over a transparent substrate, defining a transmission region for forming an actual pattern and a sub-pattern region for the transmission region, and removing portions of the photoshield metal layer and phase shift material layer disposed at the defined regions, depositing a second phase shift material layer over the resulting structure, and selectively etching back the second phase shift material layer to form phase shift material side walls, depositing over the resulting structure a photoresist film, and etching back the optional material layer such that both the first and second phase shift material layers are sufficiently exposed at their upper surfaces, etching back the first and second phase shift material layers such that they are flush with the first photoshield metal layer to form a phase shift layer at the sub-pattern region, and depositing a second photoshield material layer over the resulting structure, and etching back the second photoshield material layer to form second photoshield material side walls on the phase shift layer side walls.

Method of correcting defect of photomask and scanning probe microscope

Abstract: PROBLEM TO BE SOLVED: To provide a method of correcting the defects of a photomask which is capable of precisely removing the residual defects below 500 nm without the damage on a quartz substrate and segments exclusive of the defects after the correction of the remaining defects formed on a mask and is capable of easily detecting even the end point of the correction and a scanning probe microscope used for the same. SOLUTION: In the method of correcting the residual defects generated on the photomask formed with light shielding film patterns on a translucent substrate or the phase shift mask formed with phase shifter patterns, the method of correcting the defect of the photomask comprising acquiring the three- dimensional images of the residual defects by using the scanning probe microscope to obtain the three-dimensional images of the residual defects, then removing the residual defects by scanning the surfaces of the residual defects by the probe of the scanning probe microscope after making the load value of the probe greater than that when the three-dimensional images are acquired and the scanning probe microscope used for the same are provided.