Texas Instruments Corporation

Prutec Limited

Trialsite Limited

William C Nixon

Simon C Garth

Bernard C Breton

John T Thong

Charles E Bryan

Scanning beam apparatus adapted to display two views of a surface for stereoscopic viewing, wherein two series of electrical signals are obtained by scanning the surface with a normal and then tilted beam characterized by a frame store (36) to which the two series of electrical signals are supplied, the frame store including a feedback loop and input and feedback multiplying means (38, 40) and forming a recursive filter, and signal converter means for (42) including a red/green/blue look-up table memory means for generating red/green/blue signals for display by a color monitor (44). Alternate tilting of the beam is achieved by adjusting during alternate scans the currents flowing in the gun alignment coils (12) of the SEM so as to shift the beam, and simultaneously introducing an offset in the signals applied to at least one other element (14 or 16) in the beam forming and focusing assembly, to counteract the shift introduced by the alignment adjustment, whereby the point of intersection of the beam axes follows the focal plane as focus is altered. The two video signals may be correlated to produce a correlation signal whose value for each point in the surface indicates the apparent shift in position of that point as between the normal and tilted beam scans, to produce a signal indicative for the surface topography. The correlating signal may be converted to a focusing control signal and may be enhanced by process for successive approximations.

Charged particle beam scanning apparatus

Charged particles from a line emitter are focussed as a line image on a means for selectively blocking part of the image to produce a flat beam of controllable length. The blocking means may be an apertured plate with means for rotating and/or translating the image relative to the aperture to produce the required beam length. After passage through the aperture the beam may be twisted and/or translated to its original or some other orientation and position. The beam may be of electrons or ions and may be used in the manufacture or testing of integrated circuits. An alternative form of blocking means is a row of controllable gate electrodes which can block selected parts of the line beam; this is of particular value in producing c.r.t. displays.

Charged particle sources

Method of manufacturing a light valve

Electron detector apparatus and method for detecting secondary electrons released from a body, of particular utility in testing integrated circuits in an operational state. The apparatus utilizes a magnetic lens having an axis of symmetry, for producing a magnetic field that progressively weakens along the axis, so that the secondary electrons travel through the magnetic lens in progressively elongated helical paths and approach an electron retarding means, for example a planar grid, at approach angles to the direction of the axis such that their approach speeds along the axis are substantially equal to their actual speeds. The secondary electrons are collected after passage through the retarding means. Alternatively, the secondary electrons may be directed through a magnetic lens having an axis of symmetry to focus them at a small region at one end of the lens on which a part spherical electron retarding electrode is centered, such that the focussed secondary electrons proceed along radial paths to the retarding electrode, such that their approach speeds are substantially equal to their actual speeds.

Electron detector

Growing community of inventors

Cambridge, United Kingdom

William C Nixon