A Combined Infrared/Visible Photoemission Microscope

Author(s):  
A.D. Trigg

Abstract The photoemission microscope (PEM) is a powerful and widely used tool for location and identification of failure sites on integrated circuit (IC) chip and wafers. A PEM operating in the infrared (IRPEM) offers several advantages over systems operating in the visible part of the spectrum.. A combined PEM/IRPEM has been built having a cooled (77K) mercury cadmium telluride (MCT) focal plane array (FPA) sensitive in the range 800 to 2500 nm, an intensified charge coupled device (CCD) camera sensitive in the range 350 to 900 nm and a conventional, colour CCD camera. A cooled filter wheel enables the user to select the spectral range of the FPA. Direct comparison of photoemission images obtained in the IR and visible parts of the spectrum is straightforward, while the colour camera permits easy navigation around the device and facilitates probing of wafers. Comparing the sensitivity of the IRPEM with a conventional PEM camera (GEN III intensifier) indicates that for forward bias emission and NMOS emission the IRPEM is approximately 500 times more sensitive. Applications of the system to failure analysis in ICs, sensor devices and electronics packaging are described.

1995 ◽  
Vol 167 ◽  
pp. 213-220
Author(s):  
J. C. Cuillandre ◽  
Y. Melliers ◽  
R. Murowinski ◽  
D. Crampton ◽  
G. Luppino ◽  
...  

MOCAM is a wide field CCD camera, currently nearing completion, which will be offered to the Canada-France-Hawaii Telescope (CFHT) user community in 1995. The project is a collaboration between the CFHT, the Dominion Astronomical Observatory (DAO, Canada), the Institut des Sciences de l'Univers (INSU, France), Laboratoire d'Astrophysique de Toulouse (LAT, France) and the University of Hawaii (UH). In the interests of producing a reliable and effective camera in the shortest time, it was decided to use existing technologies rather than innovative ones. Two-edge buttable 2048 × 2048 15 μm pixel CCDs were obtained from the LORAL aerospace foundry, based on a mask designed by J. Geary at Smithsonian Astrophysical Observatory (SAO). They are mounted in a dewar designed by G. Luppino (UH); the focal plane mounting keeps the mosaic flat to within two pixels and the CCDs are aligned to within two pixels. A mechanical interface designed and fabricated by the DAO holds a 150 mm shutter and a filter wheel which has a positioning repeatability better than five μm.The four CCDs are operated in parallel by a San Diego GenIII controller adapted by LAT. The mosaic is read out in seven minutes and a single 33 Mb FITS file is generated to enable convenient on-line preprocessing. The user will control the system through a single CFHT Pegasus environment session. The camera field is 14′ × 14′ with a 0.″2 pixel sampling and the readout noise is less than seven electrons. The scientific goals of the initiators of the project are studies of distant clusters, deep galaxy counts and quasars surveys.


Author(s):  
S-H Chen ◽  
T-T Liao ◽  
C-T Chen

This study presents a rapid and reliable machine vision technique for measuring the principal features of interest in an integrated circuit carrier tape, namely the diameters of the circular sprocket perforations and centre hole, the width of the carrier tape, and the width and length of the centre cavity. In performing the measurement process, the quality of the image acquisition process is enhanced by using two auxiliary light sources to suppress the effects of natural variations in the environmental lighting conditions. Having acquired the image using a charge coupled device (CCD) camera, the features of interest are separated from the background region of the image using a two-threshold algorithm based on the Otsu threshold selection method. The edge of each feature is then extracted from the binary image using the Canny edge detection method. The dimensions of the circular features are obtained by fitting four right-angle triangles within the periphery of the extracted circular edge and then computing the circle diameter by taking the mean of the hypotenuse values of the four triangles as computed using the Pythagorean theorem.


2015 ◽  
Vol 9 (1) ◽  
pp. 170-174 ◽  
Author(s):  
Xiaoling Zhang ◽  
Qingduan Meng ◽  
Liwen Zhang

The square checkerboard buckling deformation appearing in indium antimonide infrared focal-plane arrays (InSb IRFPAs) subjected to the thermal shock tests, results in the fracturing of the InSb chip, which restricts its final yield. In light of the proposed three-dimensional modeling, we proposed the method of thinning a silicon readout integrated circuit (ROIC) to level the uneven top surface of InSb IRFPAs. Simulation results show that when the silicon ROIC is thinned from 300 μm to 20 μm, the maximal displacement in the InSb IRFPAs linearly decreases from 7.115 μm to 0.670 μm in the upward direction, and also decreases linearly from 14.013 μm to 1.612 μm in the downward direction. Once the thickness of the silicon ROIC is less than 50 μm, the square checkerboard buckling deformation distribution presenting in the thicker InSb IRFPAs disappears, and the top surface of the InSb IRFPAs becomes flat. All these findings imply that the thickness of the silicon ROIC determines the degree of deformation in the InSb IRFPAs under a thermal shock test, that the method of thinning a silicon ROIC is suitable for decreasing the fracture probability of the InSb chip, and that this approach improves the reliability of InSb IRFPAs.


Author(s):  
J. Gordon Robertson

Abstract One of the basic parameters of a charge coupled device (CCD) camera is its gain, that is, the number of detected electrons per output Analogue to Digital Unit (ADU). This is normally determined by finding the statistical variances from a series of flat-field exposures with nearly constant levels over substantial areas, and making use of the fact that photon (Poisson) noise has variance equal to the mean. However, when a CCD has been installed in a spectroscopic instrument fed by numerous optical fibres, or with an echelle format, it is no longer possible to obtain illumination that is constant over large areas. Instead of making do with selected small areas, it is shown here that the wide variation of signal level in a spectroscopic ‘flat-field’ can be used to obtain accurate values of the CCD gain, needing only a matched pair of exposures (that differ in their realisation of the noise). Once the gain is known, the CCD readout noise (in electrons) is easily found from a pair of bias frames. Spatial stability of the image in the two flat-fields is important, although correction of minor shifts is shown to be possible, at the expense of further analysis.


1997 ◽  
Vol 51 (5) ◽  
pp. 607-616 ◽  
Author(s):  
John W. Olesik ◽  
Jeffery A. Kinzer ◽  
Garrett J. McGowan

An instrument to obtain optical emission and laser-induced fluorescence images of atom or ion clouds, each produced from isolated, monodisperse droplets of sample in an inductively coupled plasma, is described. An excimer laser pumped dye laser is used to produce a large (28-mm × 24-mm) beam for saturated fluorescence from atoms or ions throughout a large portion of the ICP. An intensified charge-coupled device (ICCD) detects optical emission or laser induced fluorescence snapshot images at the focal plane of an aberration-corrected slitless spectrograph. Images produced from a single laser pulse can be detected. Double-exposure emission images with 1-μs gate times can be acquired to monitor the movement of atom or ion clouds produced from a single droplet of sample solution. Variations in the number of atoms or ions produced as a function of time (or height) in the plasma can be monitored. Excitation in the plasma can be assessed from ratios of emission to fluorescence intensities.


2002 ◽  
Vol 68 (11) ◽  
pp. 5737-5740 ◽  
Author(s):  
Ariel Maoz ◽  
Ralf Mayr ◽  
Geraldine Bresolin ◽  
Klaus Neuhaus ◽  
Kevin P. Francis ◽  
...  

ABSTRACT Bioluminescent mutants of Yersinia enterocolitica were generated by transposon mutagenesis using a promoterless, complete lux operon (luxCDABE) derived from Photorhabdus luminescens, and their production of light in the cheese environment was monitored. Mutant B94, which had the lux cassette inserted into an open reading frame of unknown function was used for direct monitoring of Y. enterocolitica cells on cheeses stored at 10°C by quantifying bioluminescence using a photon-counting, intensified charge-coupled device camera. The detection limit on cheese was 200 CFU/cm2. Bioluminescence of the reporter mutant was significantly regulated by its environment (NaCl, temperature, and cheese), as well as by growth phase, via the promoter the lux operon had acquired upon transposition. At low temperatures, mutant B94 did not exhibit the often-reported decrease of photon emission in older cells. It was not necessary to include either antibiotics or aldehyde in the food matrix in order to gain quantitative, reproducible bioluminescence data. As far as we know, this is the first time a pathogen has been monitored in situ, in real time, in a “real-product” status, and at a low temperature.


2018 ◽  
Vol 16 (36) ◽  
pp. 199-205
Author(s):  
Eman A A. Aboob

Based on nonlinear self- diffraction technique, the nonlinear optical properties of thin slice of matter can be obtained. Here, nonlinear characterization of nano-fluids consist of hybrid Single Wall Carbon Nanotubes and Silver Nanoparticles (SWCNTs/Ag-NPs) dispersed in acetone at volume fraction of 6x10-6, 9x10-6, 18x10-6 have been investigated experimentally. Therefore, CW DPSS laser at 473 nm focused into a quartz cuvette contains the previous nano-fluid was utilized. The number of diffraction ring patterns (N) has been counted using Charge - Coupled- Device (CCD) camera and Pc with a certain software, in order to find the maximum change of refractive index ( of fluids. Our result show that the fraction volume of 18x10-6 is more nonlinearity than others.


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