Abstract: An apparatus for examining a specimen with a beam of charged particles, where charging of the specimen is avoided or reduced by injecting inert gas onto the sample's surface. In order to avoid interactions with the electron optics, various embodiments are disclosed for providing a rotationally symmetrical nozzles and/or electrodes. Additionally, embodiments are disclosed wherein a plurality of gas conduits are arranged in a rotationally symmetrical manner. Alternatively, the conduit is incorporated into an element of the electron optics, such as the magnetic lens. Also, in order to reduce or eliminate interaction of the electrons with the gas molecules, embodiments are disclosed wherein the gas is pulsated, rather than continually injected.

Abstract: A two dimensional sensor array is used to collect light diffracted from the inspected substrate. The signal generated by each individual sensor is passed through a threshold. Those signals which are below the threshold are amplified and are summed up. The summed signal is then passed through a second threshold. Summed signals which pass the second threshold are flagged as indicating suspect locations on the substrate. In the preferred embodiment, the entire circuitry is provided in the form of a CMOS camera which is placed in the Fourier plane of the diffracted light.

Abstract: A system and method are presented for optical inspection of reticles by simulating the operation of a selected stepper. The system utilizes a flying spot inspection technique and includes a scanning apparatus and a detection unit. The scanning apparatus uses a laser source similar to that of the stepper of interest. First and second light directing assemblies are accommodated in the optical paths of, respectively, incident and transmitted light, and are designed so as to provide coherence of the light substantially equal to that of the stepper.

Abstract: A method of reticle inspection, comprising generating a test reticle comprising a plurality of test pattern-features thereon; manufacturing a wafer using the reticle; and determining a transfer of at least one of said plurality of pattern features from said reticle to said wafer. Preferably, a neural network is trained using the determination. Preferably, a reticle is inspected by running detected defects through the neural network to determine if the detected defect has a consequence.

Abstract: A charged particle beam column comprises: a particle source; an objective lens; a pre-lens deflection unit for deflecting a beam of charged particles away from the optical axis on such a path that the combined action of the objective lens and the pre-lens deflection unit directs the beam of charged particles towards the optical axis to hit the specimen surface from a first direction; and an in-lens deflection unit arranged in the vicinity of the objective lens for redirecting the deflected beam of charged particles on such a path that the combined action of the objective lens and the in-lens deflection unit redirects the beam of charged particles towards the optical axis to hit the specimen surface under said large beam landing angle from a second direction substantially opposite to said first direction.

Abstract: A method and apparatus for reducing speckle during inspection of articles used in the manufacture of semiconductor devices, including wafers, masks, photomasks, and reticles. The coherence of a light beam output by a coherent light source, such as a pulsed laser, is reduced by disposing elements in a light path. Examples of such elements include optical fiber bundles; optical light guides; optical gratings; an integrating sphere; and an acousto-optic modulator. These various elements may be combined as desired, such that light beams output by the element combinations have optical path length differences that are greater than a coherence length of the light beam output by the coherent light source.

Abstract: A yield enhancement system organizes defect classification and attribute information into a global classification scheme. The global classes are used to identify defect sources and to generate inspection and review plans. The system accumulates defect information in a database and continually refines the information to improve the accuracy of the classification assignments and the identification of the defect sources.

Abstract: Method and assembly are presented for focusing a charged particle beam while directing it onto a specimen. The assembly comprises a lens arrangement producing a focusing field and first and second deflectors. The first deflector is accommodated within the focusing field, and the second deflector is accommodated downstream of the first deflector with respect to the direction of beam propagation, and is operable in a predetermined manner with respect to the operational mode of the first deflector.

Abstract: A photocathode having a gate electrode so that modulation of the resulting electron beam is accomplished independently of the laser beam. The photocathode includes a transparent substrate, a photoemitter, and an electrically separate gate electrode surrounding an emission region of the photoemitter. The electron beam emission from the emission region is modulated by voltages supplied to the gate electrode. In addition, the gate electrode may have multiple segments that are capable of shaping the electron beam in response to voltages supplied individually to each of the multiple segments.

Abstract: A method and apparatus for reducing speckle during inspection of articles used in the manufacture of semiconductor devices, including wafers, masks, photomasks, and reticles. The coherence of a light beam output by a coherent light source, such as a pulsed laser, is reduced by disposing elements in a light path. Examples of such elements include optical fiber bundles; optical light guides; optical gratings; an integrating sphere; and an acousto-optic modulator. These various elements may be combined as desired, such that light beams output by the element combinations have optical path length differences that are greater than a coherence length of the light beam output by the coherent light source.

Abstract: Data converter apparatus for converting in real time data stored in an input compact format into an output expanded real time format. The data including a plurality of groups and repetition of the groups. The groups including, each, many basic geometric figures (BGF). The data converter includes a processor adapted to selecting data relating to a predetermined division, dividing and processing the data into consecutive bins according to scan order, which bins have structural correspondence to the input format. The data converter is further capable of sub-dividing the division into sub-divisions which have structural correspondence to the output format. The data processor is further capable of processing and allocating the BGFs in the bins to sub-divisions to thereby produce a division data stream in the output expanded real time format.

Abstract: A method is provided for the detection of defects on a semiconductor wafer by checking individual pixels on the wafer, collecting the signature of each pixel, defined by the way in which it responds to the light of a scanning beam, and determining whether the signature is that of a faultless pixel or of a pixel that is defective or suspect to be defective. An apparatus is also provided for the determination of such defects, which comprises a stage for supporting a wafer, a laser source generating a beam that is directed onto the wafer, collecting optics and photoelectric sensors for collecting the laser light scattered by the wafer in a number of directions and generating corresponding analog signals, an A/D converter deriving from the signals digital components defining pixel signatures, and selection systems for identifying the signatures of suspect pixels and verifying whether the suspect pixels are indeed defective.

Abstract: A defect detection system for inspecting objects such as reticles, photomasks, semiconductor wafers, flat panel displays and other patterned objects has two or more stages, whereby the object is examined separately for fine defects, by inspecting a binary level representation of the object, and for ultra fine defects, by inspecting a gray level representation of the object. The system also includes re-inspection apparatus for re-inspection of detected defects, thereby to reduce the false alarm rate, and for classifying the remaining defects by size, area and type.