An electron beam microscope includes an energy-sensitive detector to detect backscattered electrons and a signal processor for processing detection signals of the detector. The signal processor includes an analog amplifier. The signal processor also includes a window comparator having a signal input connected to an output of the analog amplifier. A signal generated at an output of the signal processor is generated based on a signal provided at an output the window comparator. The window comparator is configured to output a predetermined signal only if the amplified signal supplied to its signal input is less than or equal to an upper threshold and greater than or equal to a lower threshold.

Methods are disclosed to detect plasma light emissions during plasma processing, to analyze light intensity data associated with the plasma source, and to adjust operating parameters for the plasma source and/or the process chamber based upon light intensity distributions associated with the plasma processing. The light intensity distributions for the plasma sources and related analysis can be conducted across multiple processing tools. For some embodiments, plasma discharge stability and/or chamber-to-chamber matching information is determined based upon light intensity data, and the operation of the processing tools are adjusted or controlled based upon stability and/or matching determinations. The disclosed embodiments thereby provide simple, low-cost solutions to assess and improve plasma sources and discharge stability for plasma processing tools such as plasma etch and deposition tools.

An electron sensor and a system with a plurality of electron sensors for electron microscopy using an electron microscope. More specifically, the electron microscope generates an electron beam that includes at least one electron that impacts on a lateral reception surface of said electron sensor and this generates an electrical charge of electron-hole (e-h) pairs that are detected and/or measured by at least electrodes linked to an electric circuit unit to form a high dynamic range image and measure the energy of the electrons impacting each pixel of the image.

A detector may be provided for a charged particle apparatus comprising: a sensing element including a diode; and a circuit configured to detect an electron event caused by an electron impacting the sensing element, wherein the circuit comprises a voltage monitoring device and a reset device, wherein the reset device is configured to regularly reset the diode by setting a voltage across the diode to a predetermined value, and wherein the voltage monitoring device is connected to the diode to monitor a voltage across the diode in between resets.

A monolithic detector may be used in a charged particle beam apparatus. The detector may include a plurality of sensing elements formed on a first side of a semiconductor substrate, each of the sensing elements configured to receive charged particles emitted from a sample and to generate carriers in proportion to a first property of a received charged particle, and a plurality of signal processing components formed on a second side of the semiconductor substrate, the plurality of signal processing components being part of a system configured to determine a value that represents a second property of the received charged particle. The substrate may have a thickness in a range from about 10 to 30 m. The substrate may include a region configured to insulate the plurality of sensing elements formed on the first side from the plurality of signal processing components formed on the second side.

An electron microscope comprising: A specimen holder, for holding a specimen; An electron beam column, for producing an array of electron beams and concurrently irradiating an array of target areas of said specimen therewith; A scanning assembly, for producing relative scanning motion of said beam array with respect to the specimen; A detector, for detecting radiation emanating from the specimen in response to said irradiation,
wherein said detector is: A backscattered electron detector that can be disposed proximal to the specimen at a side thereof facing said electron beam column; Provided with an array of apertures that allow passage of said electron beams from said column to the specimen; Provided with a functionally sub-divided detection surface that enables segregated detection of a backscattered electron flux produced by each individual beam.

A detector may be provided with an array of sensing elements. The detector may include a semiconductor substrate including the array, and a circuit configured to count a number of charged particles incident on the detector. The circuit of the detector may be configured to process outputs from the plurality of sensing elements and increment a counter in response to a charged particle arrival event on a sensing element of the array. Various counting modes may be used. Counting may be based on energy ranges. Numbers of charged particles may be counted at a certain energy range and an overflow flag may be set when overflow is encountered in a sensing element. The circuit may be configured to determine a time stamp of respective charged particle arrival events occurring at each sensing element. Size of the sensing element may be determined based on criteria for enabling charged particle counting.

The present disclosure describes a detector used in critical dimension scanning electron microscopes (CD-SEM) and review SEM systems. In one embodiment, the detector includes a semiconductor structure having a p-n junction and a hole through which a scanning beam is passed to a target. The detector also includes a top electrode for the p-n junction (e.g., anode or cathode) that provides an active area for detecting electrons or electromagnetic radiation (e.g., backscattering from the target). The top electrode has a doped layer and can also have a buried portion beneath the doped layer to reduce a series resistance of the top electrode without changing the active area. In another embodiment, an isolation structure can be formed in the semiconductor structure near sidewalls of the hole to electrically isolate the active area from the sidewalls. A method for forming the buried portion of the top electrode is also described.

A scanning electron microscope incorporates a multi-pixel solid-state electron detector. The multi-pixel solid-state detector may detect back-scattered and/or secondary electrons. The multi-pixel solid-state detector may incorporate analog-to-digital converters and other circuits. The multi-pixel solid state detector may be capable of approximately determining the energy of incident electrons and/or may contain circuits for processing or analyzing the electron signals. The multi-pixel solid state detector is suitable for high-speed operation such as at a speed of about 100 MHz or higher. The scanning electron microscope may be used for reviewing, inspecting or measuring a sample such as unpatterned semiconductor wafer, a patterned semiconductor wafer, a reticle or a photomask. A method of reviewing or inspecting a sample is also described.

A method of operating a charged particle microscope comprising the following steps: Providing a specimen on a specimen holder; Using a source to produce a beam of charged particles that is subject to beam current fluctuations; Employing a beam current sensor, located between said source and specimen holder, to intercept a part of the beam and produce an intercept signal proportional to a current of the intercepted part of the beam, the beam current sensor comprising a hole arranged to pass a beam probe with an associated probe current; Scanning said probe over the specimen, thereby irradiating the specimen with a specimen current, with a dwell time associated with each scanned location on the specimen; Using a detector to detect radiation emanating from the specimen in response to irradiation by said probe, and producing an associated detector signal; Using said intercept signal as input to a compensator to suppress an effect of said current fluctuations in said detector signal,
wherein: The beam current sensor is configured as a semiconductor device with a sensing layer that is oriented toward the source, in which: Each charged particle of said intercepted part of the beam generates electron/hole pairs in said sensing layer; Generated electrons are drawn to an anode of the semiconductor device; Generated holes are drawn to a cathode of the semiconductor device, thereby producing said intercept signal.