Wafer Plane Inspection (WPI) is a novel approach to inspection, developed to enable high inspectability on fragmented
mask features at the optimal defect sensitivity. It builds on well-established high resolution inspection capabilities to
complement existing manufacturing methods. The production of defect-free photomasks is practical today only because
of informed decisions on the impact of defects identified. The defect size, location and its measured printing impact can
dictate that a mask is perfectly good for lithographic purposes. This inspection - verification - repair loop is timeconsuming
and is predicated on the fact that detectable photomask defects do not always resolve or matter on wafer.
This paper will introduce and evaluate an alternative approach that moves the mask inspection to the wafer plane. WPI
uses a high NA inspection of the mask to construct a physical mask model. This mask model is used to create the mask
image in the wafer plane. Finally, a threshold model is applied to enhance sensitivity to printing defects. WPI essentially
eliminates the non-printing inspection stops and relaxes some of the pattern restrictions currently placed on incoming
photomask designs. This paper outlines the WPI technology and explores its application to patterns and substrates
representative of 32nm designs. The implications of deploying Wafer Plane Inspection will be discussed.
Hyperspectral image data can provide very fine spectral resolution with more than 200 bands, yet presents challenges for
visualization techniques for displaying such rich information on a tristimulus monitor. This study developed a
visualization technique by taking advantage of both the consistent natural appearance of a true color image and the
feature separation of a PCA image based on a biologically inspired visual attention model. The key part is to extract the
informative regions in the scene. The model takes into account human contrast sensitivity functions and generates a
topographic saliency map for both images. This is accomplished using a set of linear "center-surround" operations
simulating visual receptive fields as the difference between fine and coarse scales. A difference map between the
saliency map of the true color image and that of the PCA image is derived and used as a mask on the true color image to
select a small number of interesting locations where the PCA image has more salient features than available in the
visible bands. The resulting representations preserve hue for vegetation, water, road etc., while the selected attentional
locations may be analyzed by more advanced algorithms.
Proc. SPIE. 6233, Algorithms and Technologies for Multispectral, Hyperspectral, and Ultraspectral Imagery XII
KEYWORDS: Hyperspectral imaging, Principal component analysis, Independent component analysis, Visualization, Sensors, Colorimetry, Associative arrays, Human vision and color perception, Color vision, RGB color model
This study investigated appropriate methodologies for displaying hyperspectral imagery based on knowledge of human color vision as applied to Hyperion and AVIRIS data. Principal Component Analysis (PCA) and Independent Component Analysis (ICA) were used to reduce the data dimensionality in order to make the data more amenable to visualization in three-dimensional color space. In addition, these two methods were chosen because of their underlying relationships to the opponent color model of human color perception. PCA and ICA-based visualization strategies were then explored by mapping the first three PCs or ICs to several opponent color spaces including CIELAB, HSV, YCrCb, and YUV. The gray world assumption, which states that given an image with sufficient amount of color variations, the average color should be gray, was used to set the mapping origins. The rendered images are well color balanced and can offer a first look capability or initial classification for a wide variety of spectral scenes.
Single mode 650 nm AlGaInP quantum well laser diodes grown by low pressure metal organic chemical vapor deposition was reported in this paper. Selected buried rigewaveguide were applied for single mode operation especially for DVD use. The operating temperature over 90 degree at CW output power 5 mW was achieved.
High performance uncooled 1.55 micrometers InGaAsP/InP strained layer quantum well lasers grown by low pressure metal organic chemical vapor deposition (LP-MOCVD) were reported in this paper. Whole MOCVD over growth method were applied in this work. The threshold currents of 5 mA and the highest lasing temperature of 122 degree(s)C were obtained.
Low threshold current and high temperature operation of 650nm AlGaInP quantum well laser diodes grown by low pressure metal organic chemical vapor deposition are reported in this paper. 650nm laser diodes with threshold current as low as 22-24mA at room temperature, and the operating temperature over 90 degrees C at CW output power 5 mW were achieved in this study. These lasers are stable during 72 hours burn in under 5mW at 90 degrees C.
High performance 1.3 micrometers and 1.55 micrometers InGaAsP/InP strained layer quantum well (SL-QW) lasers grown by low pressure metal organic chemical vapor deposition are reported in this paper. 1.3 micrometers SL-QW lasers and 1.55 micrometers SL-QW lasers with broad area threshold current densities as low as 400 A/cm2 and 450 A/cm2 (at cavity length 400 micrometers ), DC-PBH stripe device threshold currents of 5 approximately 10 mA and 6 approximately 10 mA were obtained, respectively. The prediction life time of 1.3 micrometers SL-QW lasers is more than 106 hrs at 25 degree(s)C, and degeneration activated energy is 0.682 eV according to the accelerate aging tests.