Abstract: Focused ion bean (FIB) milling through a power plane of a device to expose or cut a hidden, lower-layer conductor requires accurate positioning relative to the hidden conductor of a box defining boundaries of the FIB operation. This can in general be done by aligning surface information (topology or voltage contrast) visible in a FIB or scanning electron microscope (SEM) image with an overlay image generated from stored data describing the device. The location of the hidden conductor relative to the visible surface information is determined from the stored data. Advanced integrated circuits often do not provide enough unique surface information near the FIB operation area to align the images with sufficient accuracy.

Abstract: Methods and apparatus are disclosed for positioning the field of view in a system for IC probing or repair, where the system comprises means for supporting an IC device having multiple physical layers and multiple internal nets, and controllable positioning means for positioning the field of view relative to the device. A data set is prepared which describes each physical layer of the device as a plurality of reduced polygons. Each of the reduced polygons is associated with a physical layer of the device and with at least one net of the device. For each of a plurality of selected nets, polygons associated with the net are dilated to define the periphery of a region encompassed by the field of view when a point within the field of view is traced around the periphery of a reduced polygon. A bit plane of the dilated polygons is mapped for each net, and regions of overlap the mapped bit planes are identified.

Abstract: Focused ion beam (FIB) systems are used for IC mask or reticle repair and imaging and other applications. The impinging ions can cause an undesirable charge build-up on the specimen. Prior to beginning repair operations in a FIB system, a fluid containing a conductive material such as dimethyl ammonium salt is applied to the reticle, mask or device and allowed to dry, leaving a thin conductive layer on the specimen. A leakage path is preferably provided from the thin conductive layer to ground, to prevent charge buildup on the specimen. The FIB is used to cut through the conductive layer before commencing FIB deposition, to assure proper bonding of the deposited material. The technique also has application with electron beam imaging systems.

Abstract: An electron-beam test probe system (400) in which a pulsed laser-beam source (404) and a photocathode assembly (430) are used with an electron-beam column (426) to produce a pulsed electron beam at a stabilized repetition frequency. A pulse picker (414) allows the pulse repetition frequency of the pulsed electron beam to be reduced to a submultiple of the pulsed laser repetition frequency. A test pattern generator (416) is programmable to apply a desired pattern of test vector patterns to an electronic circuit to be probed, the test vector patterns being synchronized with the stabilized laser-beam pulse repetition frequency. A timebase circuit (412) allows the test vector patterns to be time-shifted relative to the pulsed electron beam. The electronic circuit under test can thus be probed at any desired point in the applied test vector pattern by control of the pulse picker and by time-shifting the test vector pattern.

Abstract: A surface is probed with a pulsed electron beam and secondary electrons are detected to produce a detector signal. First portions of the detector signal are substantially dependent on the voltage of the surface being probed, while second portions of the detector signal are substantially independent of the voltage of the surface being probed. In general, the first and second portions of the detector signal include unwanted noise caused by low-level sampling due to beam leakage and/or by scintillator afterglow in the secondary-electron detector. The detector signal is sampled during the first signal portions and is sampled during the second signal portions. The sampled first signal portions are combined with the complement of the sampled second signal portions to produce a measured voltage signal representing voltage of the conductor. In a preferred sampling scheme, alternate electron-beam sampling pulses are held-off.

Abstract: Methods and apparatus are disclosed for conditional acquisition of potential measurements in integrated circuits, with the aid of electron-beam probes. The conditional acquisition enables display of waveform images which permit diagnosis of the causes and/or origins of failure in circuits which fail intermittently. Data is acquired in the normal manner on each pass through the test pattern. At the end of each test pattern execution a pass/fail signal from the tester exercising the circuit is used to reject or accept the acquired data. In this fashion, it is possible to accumulate only that data which carries information about the failure of interest and to reject data which does not. Over several test pattern repetitions it is possible to display only that data which shows the failure. Engineers are thus able to efficiently diagnose intermittent failures without the need to change device operating parameters.

Abstract: Apparatus is provided which includes a FIB column having a vacuum chamber for receiving an IC, means for applying a FIB to the IC, means for detecting secondary charged particles emitted as the FIB is applied to the IC, and means for electrically stimulating the IC as the FIB is applied to the IC. The apparatus may be used, for example, (1) to locate a conductor buried under dielectric material within the IC, (2) for determining milling end-point when using the FIB to expose a buried conductor of the IC, and (3) to verify the repair of an IC step-by-step as the repair is made.

Abstract: The present invention provides methods and apparatus for rapid compression of images composed of pixels into high-resolutions, compressed icon images, and for dynamic fault imaging of operating faults in integrated circuit devices employing such methods. Displaying a plurality of such icons juxtaposed on a screen permits ready tracing of a fault in an IC device under test, even by persons having little knowledge of the functionality of the devices.In accordance with the invention, an image made up of n.times.n pixels may be compressed into an icon of p.times.p pixels, where n.dbd.P.multidot.q and q is an integer, by dividing the image into p tiles of q.times.q pixels, selecting q pixels from each tile, where each of said selected q pixels is representative of predetermined directional orientations within the tile, and calculating the mean value of the selected q pixels, to produce a single pixel representative of the tile. The pixels representative of said tiles thus form an icon of p.times.p pixels.

Abstract: Methods and apparatus are disclosed for rapid and interactive "warping" of a first image made up of pixels to form a resulting image made up of pixels which are aligned, pixel-for-pixel, with a second image made up of pixels. The images may be stroboscopic voltage contrast images representing operating states of two integrated circuit devices--a failing device and a fully functional device. The aligned images permit an engineer who may have little knowledge of the device to diagnose dynamic failures of the failing device by comparing the aligned images to produce an image showing the differences.

Abstract: Methods are disclosed which provide for quantifying and characterizing the mineral content of a formation as a function of depth. Elemental data derived from logging tools are input into an element-mineral transform operation, preferably a matrix which is constructed using multivariate statistical analysis on previously available data, to determine the quantity of at least one or more dominant minerals in the formation. From the mineral quantity information and the elemental log data, the formation minerals are further characterized. Information regarding the character and quantities of formation minerals is further used to obtain improved determinations of formation characteristics such as the cation exchange capacity and water saturation, and the grain density and formation porosity, as well as to obtain an increased understanding of the formation such as the depositional environment of the formation.

Abstract: A method for acoustically investigating characteristics of formations penetrated by a borehole such as fractures by taking differential Stoneley wave acoustic energy measurements between pairs of receivers of an array of receivers carried by a logging tool. The receivers of each pair all have the same spacing. The energy is that detected by the receivers in response to acoustic pulses generated by a transmitter spaced from the receivers on the tool. The differential energy measurements are stacked to obtain a stacked differential energy log.

Abstract: In order to increase the angular field of observation of a logging sonde usable, in particular for dip metering, the sonde is equipped with measuring pads each comprising two independent flaps. The flaps of the same pad are hinged to a central element which is held permanently parallel to the axis of the sonde body, and they are applied against the wall of a borehole by blade springs. Each of the flaps carries an array of electrodes. The flaps of each of the measuring pads are circumferentially offset relative to each other so that the angular field of observation is increased without increasing the diameter of the sonde, once the pads have been retracted.

Abstract: Apparatus and method for investigating a borehole casing. The preferred apparatus generally comprises: a housing which is connected to a cable; sets of electrodes, each set being axially spaced from another set, with the electrodes in each set being circumferentially spaced at an axial depth; a positioning device provided in the housing for bringing the electrodes into contact with the casing; a measuring circuit provided inside of the housing and electrically connected to the electrodes for measuring at least the potential difference of the casing between the electrode locations, wherein the potential difference information is amplified by the measuring circuit, and the amplified information is transmitted through the cable for processing; and a control circuit provided in the housing for controlling the operation of the positioning device and the measuring circuit.

Abstract: A method of velocity filtering seismic signals and an installation for implementing the method. A two-dimensional signal g(z,t) is available built up from a set of signals .sub.i (t) for I>i>n as produced by sound wave detectors located at different depths z.sub.1, . . . z.sub.n in a borehole in response to sound waves being emitted from a source as seismic waves, with said detected signals including upgoing waves and downgoing waves. In order to reinforce the upgoing waves (or conversely the downgoing waves) in the signal g(z,t), an operator A is applied recursively to said signal, where: A=1/2[Id+.epsilon..B.H.sub.t.D.sub.z ] where: Id is the identity operator; .epsilon.=+1(or -1); B is normalization factor whose value depends on the signal g(z,t) to which the operator A is applied; H.sub.t is the one-dimensional Hilbert operator relating to the variable t; and D.sub.z is a differentiation operator relating to the variable z.

Abstract: The invention is directed to a locking mechanism for locking a tool to an anchor seat located in the tubing of a well, the locking mechanism comprising keys which are radially movable relative to the axis of the tool, the keys emerging via apertures in the body of the tool to engage in a groove of an anchor seat located in the well conduit. The groove of the anchor seat has an internal diameter smaller than the internal diameter of the well conduit. Each key is axially movable within the aperture between a high position and a low position. Structure is provided for retaining the keys in the high position, positioning the keys in a radially retracted position, so that the keys do not cause the tool to be secured in the anchor seat. Structure is also provided for positioning the keys in a radially extended position, causing the keys to contact the groove of the anchor seat, thereby locking the tool to the anchor seat.

Abstract: The present invention is directed to a method of inverting seismic traces Sk by determining the series R={r.sub.i } representative of the seismic reflection coefficients from geological strata. The method includes the steps of determining an approximate solution to R.degree. by minimizing an entropy type function H(R)=.SIGMA.f(r.sub.i) under constraints related to the upgoing wavefield Uk and the downgoing wavefield Dk; determining a correction value .DELTA.R by minimizing a linear function J(.DELTA.R) under linear constraints related to the noise in the traces and to the time-depth curve extracted from the traces; and calculating R=R.degree.+.DELTA.R, representative of the reflection coefficients. In a variant, the selection of the approximate solution R.degree. is guided by taking into account information contained in one or more logs, and determining .DELTA.R so that the series R satisfies the stacking velocities which result from surface seismic processing.

Abstract: A method and system for computer programming provides a graphical editor function for creation and editing of a computer program by manipulation of graphical images on a high-resolution display. The program is specified in terms of a definition language which can be executed by a simulation function. This function simulates execution of the program on a different, target processor as if the program were expressed in a different language which can be executed by the target processor; in addition the simulation function incorporates a simulation of the external environment of the target processor and of the interaction of the program with that environment. The graphical display of the program is animated during execution so that the user can observe and check the program's operation. When the simulated execution is satisfactory the definition-language version of the program is tanslated into the language executable on the target processor.

Abstract: Waveform data obtained in a borehole by a tool having a sonic source and an array of sonic detectors is analyzed to obtain an image of formation features within several tens of feet of the borehole, such as fractures, bed boundaries and other boreholes. A value of background sonic slowness is derived from the data and used to determine the sonic energy transit time from the source to each detector via each point in a grid of points extending into the formation and along the borehole. The time for a particular detector/point pair is used to extract the amplitude of the waveform from that detector at that time relative to operation of the source. Such amplitudes for the same point and for different detectors and tool positions are cumulated. The final values for all points are plotted as a variable density display which provides the desired image.

Abstract: Three-axis vertical seismic profile measurements are analyzed to derive values for the velocity v.sub.p and angel of incidence .PSI..sub.p of a plane compressional wave at the borehole and for the shear wave velocity v.sub.s and angle of incidence .PSI..sub.s of a plane shear wave at the borehole. In the described embodiment this is accomplished by finding values for these parameters which maximize the expression.SIGMA..sub..omega. .vertline.(a.sub.p +a.sub.s).sup.H u(.omega.).vertline..sup.2 /.parallel.a.sub.p +a.sub.5 .parallel..sup.2 +.vertline.(a.sub.p -a.sub.s).sup.H u(.omega.).vertline..sup.2 /.parallel.a.sub.p -a.sub.s .parallel..sup.2where.omega. is angular frequency;a.sub.p and a.sub.s are column vectors representing compressional and shear wave particle motions at frequency .omega. at a multiplicity of locations in the borehole;u(.omega.) represents components in a plane of waveform measurements obtained at these locations;.parallel. .parallel.

Abstract: Systems, for investigating casings which are fitted into boreholes that traverse earth formations and which are suitable for use in evaluating and/or optimizing the cathodic protection of casings and for finding the location and rate of casing corrosion, generally includes a downhole tool capable of investigating the casing along a measurement control unit located around the surface of the earth formation, and a cable having one end connected to the downhole tool and the other connected to the measurement control unit, with the cable including at least a plurality of first connection lines. The tool invention generally includes at least a first pair of longitudinally spaced electrodes, at least a pair of second connection lines, each of the second connection lines having one end connected to a corresponding one of the electrodes, and relays interposed between the first connection lines and the second connection lines.