82 results about "Langmuir probe" patented technology

A plasma processing system is provided with diagnostic apparatus for making in-situ measurements of plasma properties. The diagnostic apparatus generally comprises a non-invasive sensor array disposed within a plasma processing chamber, an electrical circuit for stimulating the sensors, and means for recording and communicating sensor measurements for monitoring or control of the plasma process. In one form, the sensors are dynamically pulsed dual floating Langmuir probes that measure incident charged particle currents and electron temperatures in proximity to the plasma boundary or boundaries within the processing system. The plasma measurements may be used to monitor the condition of the processing plasma or furnished to a process system controller for use in controlling the plasma process.

There is provided by this invention a wafer probe for measuring plasma and surface characteristics in plasma processing environment that utilizes integrated sensors on a wafer substrate. A microprocessor mounted on the substrate receives input signals from the integrated sensors to process, store, and transmit the data. A wireless communication transceiver receives the data from the microprocessor and transmits information outside of the plasma processing system to a computer that collects the data during plasma processing. The integrated sensors may be dual floating Langmuir probes, temperature measuring devices, resonant beam gas sensors, optical emission sensors, or other sensors of plasma or surface properties. There is also provided a self-contained power source that utilizes the plasma for power that is comprised of a topographically dependent charging device or a charging structure that utilizes stacked capacitors.

A Langmuir probe for measuring characteristics of a plasma driven by radio frequency (RF) power comprises an elongated conductor 10 having an exposed tip 1 for insertion into an RF plasma and an outer end 3 for connection to external measuring circuitry. In order to reduce distortion over a range of RF frequencies, the probe includes an RF voltage divider 11, 12, 13, 14 in series between the tip and outer end of the conductor.

The invention relates to a method for acquiring a voltage-current characteristic curve of plasma. The method is characterized in that plasma parameters are probed by using a Langmuir probe under the condition of radio-frequency discharge mode; a point to be probed is probed by the Langmuir probe under the control of a scanning voltage to acquire sampling values of the parameters, thereby, the voltage-current characteristic curve of the plasma is acquired, wherein one-time probe working time comprises a plurality of discharge cycles; the stable scanning voltage is applied to the Langmuir probe during the same discharge cycle; and each discharge cycle corresponds to one different scanning voltage.

The invention discloses an active control device and method for a spacecraft structure potential. The device comprises a Langmuir probe, a hollow cathode and an extraction electrode. The Langmuir probe is arranged on one side of the hollow cathode and arranged on the outer wall of a spacecraft structure, the hollow cathode is arranged outside the spacecraft structure, the hollow cathode is connected with a structure ground of the spacecraft, the extraction electrode is arranged opposite to a nozzle of the hollow cathode, and the extraction electrode is connected with a power source. The control method includes the steps that the Langmuir probe is started, the structure potential of the spacecraft is obtained, then the hollow cathode and the extraction electrode are controlled to emit electrons to space, and therefore the structure potential of the spacecraft is controlled. The active control device and method have the advantages that the structure potential of the spacecraft can be rapidly decreased; the structure potential of the spacecraft can be kept about 0V; by changing the gas flow and a potential of the extraction electrode, the requirements for controlling structure potentials of spacecrafts different in orbit and structure can be met.

The invention discloses a cylindrical probe used for plume measurement of a magnetic plasma thrustor. The cylindrical probe includes single probe modules, a four-hole ceramic tube and a Langmuir probe protection tube module. The single probe module includes a thick single-hole ceramic tube, a thin single-hole ceramic tube and a tungsten filament. One end of the thin single-hole ceramic tube and one end of the thick single-hole ceramic tube are flush to each other and are fixed to each other. The tungsten filament is inserted to the thin single-hole ceramic tube. An end face of the four-hole ceramic tube is provided with four through holes. Three identical single probe modules are inserted into three of the four through holes. The Langmuir probe protection tube module includes a protection tube, a flat gasket, a fastening screw, a nut and a spring gasket. The four-hole ceramic tube with the fixed single probe modules is inserted from the protection tube and gets fixed. The cylindrical probe provided by the invention has advantages that the four-hole ceramic tube, the thick single-hole ceramic tube, the thin single-hole ceramic tube and the tungsten filament made of aluminum oxide which is common in market can bear plume temperature of the magnetic plasma thrustor; structural stability can be kept through clearance fit; and the cylindrical probe is simple in structure.

The invention discloses a highly-integrated Langmuir probe diagnosis system and method. The highly-integrated Langmuir probe diagnosis system comprises a Langmuir probe, a trigger, a scanning power supply, a data acquisition unit and a data processing unit. The trigger transmits a pulse trigger signal to the scanning power supply via an optical fiber to trigger generation of sawtooth voltage with designated amplitude, period and repeat account, and the sawtooth voltage is loaded onto the Langmuir probe; the data acquisition unit carries out rapid, multiple and synchronous acquisition and storage on the voltage and current data of the Langmuir probe; and after completion of data acquisition, all the results are sent to the data processing unit in one shot, a data processing program on a computer is employed for automatic processing and analysis, and an acquired volt-ampere characteristic curve and acquired plasma parameters are displayed. The highly-integrated Langmuir probe diagnosis system has high automation degree and integrated level, can realize high-speed synchronous data acquisition and large-quantity data storage and communication, employs data processing for automatic processing and analysis of acquired data and provides a good man-machine interaction interface for displaying and recording of processing results.

A wafer integrated plasma diagnostic apparatus for semiconductor wafer processing system having a multiplicity of plasma probe assemblies arranged on a wafer in a planar array fashion such that one plasma probe assembly is in the center and eight more plasma probe assemblies are at intermediate positions such that they lie along the radius from the center to the corners; such corners forming four corners of a square box near the edge of the wafer. At each location and in each of the plasma probe assemblies, there are six possible probe elements having a relative geometrical area such that they are capable of making simultaneous measurements of both spatial resolution and real time measurement of different plasma characteristics at the wafer surface, such as: D.C. potential, A.C. potential, shading induced potentials, ion fluxes, ion energy distribution, and the electron part of the I-V Langmuir probe characteristic.

The invention discloses a fast electron measurement probe system suitable for magnetic confinement plasma. The fast electron measurement probe system comprises an insulating shell, a fast electron probe assembly, a Langmuir probe assembly and a ceramic base. The insulating shell is formed by processing high-temperature-resistant boron nitride, the ceramic base is made of machinable ceramic, a plurality of Langmuir probes are distributed at the front end of the probe system, and a plurality of fast electron probes are uniformly and symmetrically distributed on two side surfaces of the probe system and are used for collecting electron current. The fast electronic probe and the Langmuir probe respectively comprise a graphite probe, a copper binding post, a wire and the like, the graphite probes and the copper binding posts are connected through threads, the copper binding posts and the wire are connected through crimping pliers in a crimping mode, connection is reliable, and high temperature resistance is achieved. According to the fast electron probe, the radius of an electron Larmor in magnetic confinement plasma is far smaller than that of ions, and the ions can be effectively repelled by setting the width and the depth of a small hole to collect electrons. The system can work in a high-temperature environment in the magnetic confinement fusion device, and is stable in mechanical performance, reliable in signal, high in spatial resolution and small in occupied space.

This invention relates to a Langmuir probe plasma diagnosis method based on a virtual instrument for diagnosing spacial potential, charge density and electronic temperature of plasmer characterizing in using a quasi-DC probe bias signal to replace conventional sawtooth wave scan bias signal and utilizing a virtual instrument to replace conventional scan signal generator to generate a probe bias signal and collect and analyze its voltage and current signals, which does not need to collect voltage and current signals synchronously and increases the S/N ratio of data by multiple collections, and further changes the collection rate flexibly to overcome the interference of fluctuation of plasma.

The invention relates to a microwave and plasma interacting device in magnetic plasma, in particular to a microwave and plasma interacting device in magnetic plasma under the condition that a magnetic field and an electric field are perpendicular. The microwave and plasma interacting device aims to solve the problem that no microwave and plasma interacting device under the characteristic situation of the different magnetic plasma exists in the prior art. The microwave and plasma interacting device comprises a microwave generator, a ferrite isolator, an attenuator, a directional coupler, a waveguide tube, an insulation microwave window, a vacuum cavity, a plurality of solenoids, a diaphragm, a plasma source, two Langmuir probes, a cut-off tube, a matching microwave load, a loop antenna, a magnetic probe, an electrostatic probe, a multiple-grid probe and a plasma visualizer, wherein the plasma source is a sparking plasma source, generated sparking voltage is used for controlling the density of the plasma, and the attenuator is used for adjusting microwave power. The microwave and plasma interacting device is used for researching the interaction between the microwave and the plasma under the characteristic condition of the different magnetic plasma.

The invention discloses a Langmuir probe, a Langmuir probe diagnostic system and a diagnostic method thereof, which relate to the technical field of plasma. The Langmuir probe according to the invention comprises a collector, an electrically conductive screw lead, a ceramic sheath and a hexagon nut; the conductive screw lead is screwed into the collector and connected with the collector, the ceramic sheath is arranged on the conductive screw lead, and one end part is in contact with the collector, and the hexagon nut is screwed with the conductive screw lead and in contact with the other end part of the ceramic sheath; The Langmuir probe can avoid the contact between the lead wire and the plasma, eliminate the lead wire interference and reduce the measurement error.

The invention provides a method and a device for equivalently measuring terahertz wave transmission characteristics in a plasma sheath. The method comprises the following steps: acquiring the electrondensity and distribution of a target plasma sheath in a Langmuir probe mode; carrying out simulation modeling on the target plasma sheath according to the electron density and distribution of the target plasma sheath, and simulating the target plasma sheath by adopting equivalent plasma generated by high-voltage discharge; and equivalently measuring the transmission characteristic of the terahertz wave in the target plasma sheath according to the transmission characteristic of the terahertz wave in the equivalent plasma generated by high-voltage discharge. The technical bottleneck that at present, terahertz wave energy is weak, and terahertz wave transmission characteristic experimental data in a plasma sheath cannot be directly obtained is solved. Therefore, the equivalent measurement ofthe transmission characteristics of the terahertz waves in the plasma sheath is fully carried out.

The invention discloses a method and system for measuring electron temperature and plasma density in a galatea magnetic well. The system comprises a Langmuir probe module, a peripheral circuit module,a signal selection module, a signal acquisition module and a signal processing module; the Langmuir probe module comprises a plurality of Langmuir probes arranged in an array mode, and the total number and the positions of the Langmuir probes are decided by the plasma distribution condition in the galatea magnetic well, the magnitude order of the electron temperature and the plasma density and spatial configuration of a magnetic field region; the peripheral circuit module is connected with the Langmuir probe module and is used for detecting a current signal in each Langmuir probe and a voltage signal at the two ends of the probe; the signal selection module is connected with the peripheral circuit module and is used for selectively receiving the current signals and the voltage signals ofthe Langmuir probes; the signal acquisition module is connected with the signal selection module; the signal processing module is connected with the signal acquisition module and is used for obtaininga characteristic curve of the Langmuir probes according to the current signals and the voltage signals acquired by the Langmuir probes and further calculating the electron temperature and plasma density of each channel. The method and the system are convenient, rapid, accurate, high in efficiency and high in reliability.

The invention provides a Langmuir probe sensor used on a sounding rocket. The Langmuir probe sensor comprises an upper hemisphere (1), a lower hemisphere (2), a connecting rod (4), a telescopic rod and a signal wire, wherein the upper hemisphere (1), the lower hemisphere (2) and the connecting rod (4) are in cavity structures; the upper hemisphere (1) and the lower hemisphere (2) are connected through an insulating partition plate (3); one end of the connecting rod (4) penetrates in along a central shaft at one side of the spherical surface of the lower hemisphere (2); the connecting rod (4) and the lower hemisphere (2) are connected and fixed through an insulating pad (6) embedded in one end of the connecting rod (4), the other end of the connecting rod (4) is connected and fixed together with the telescopic rod; one end of the signal wire is connected with the upper hemisphere (1), the other end of the signal wire (1) penetrates through the insulating pad (6) and the inner cavity of the upper hemisphere (1), and is guided out from the inner cavity of the connecting rod (4); the upper hemisphere (1) is used as a collecting electrode, and the lower hemisphere (2) is used as a protective pole.

Provided is a technique capable of ascertaining the process condition of the boundary between electrically positive and negative plasma regions. In a vacuum chamber, one of the parameters of process conditions is stepwisely changed to generate a plasma under at least three process conditions. The parameters include a flow rate ratio between an electrically negative gas and an electrically positive gas, a pressure in the vacuum chamber and the magnitude of an energy supplied to the gases. Next, a voltage is applied to a Langmuir probe positioned in that plasma, and a current-voltage curve indicating the relationship between the applied voltage and the electric current to flow through the probe is acquired for each of the process conditions. On the basis of the current-voltage curve group acquired, the process conditions are determined for the boundary between the electrically positive and negative plasma regions.

The invention discloses a probe and method for measuring plasma space potential by the aid of bias currents. The method includes: acquiring relative coupling potential by coupling the spherical probe with plasma around the spherical probe; allowing 'suspension type' constant-current source circuit to applying the bias current to the probe; internally installing a high-impedance coupling potential detection circuit and a bias current circuit in the spherical probe; allowing a signal processing unit to process coupling potential signals of the probes and provide control voltage signals to the bias current. The equivalent mode of application of the bias current is adopted for the probe, floating point potential of the probe is changed and approaches to plasma space potential around the floating point potential; plasma parameters are diagnosed according to the Langmuir probe, the initial value of the applied bias current is acquired from calculation, and rapid convergence of the bias current value is realized; the plasma space potential is finally acquired through final measurement with a continuous bias current increasing method; thermionic emission of the emission probe and space-charge effect thereof can be avoided, and measurement precision of the probe on the plasma space potential can be improved.

The invention discloses a device for cleaning the contaminants on the surface of a spherical Langmuir probe, comprising a hollow spherical Langmuir probe, a cleaning halogen lamp, a ceramic halogen lamp bracket, a coaxial lead for the power supply of the cleaning halogen lamp, a temperature measuring resistor, a coaxial lead for supplying power to the temperature measuring resistor, a hollow columnar spherical Langmuir probe bracket, a ceramic insulating base, a temperature measuring power supply interface and a cleaning halogen lamp power supply interface. One end of coaxial lead for the power supply of the cleaning halogen lamp penetrates through hollow columnar spherical Langmuir probe bracket and the ceramic halogen lamp bracket and is connected with the cleaning halogen lamp, and the other end is connected with the power supply of the cleaning halogen lamp; the temperature measuring resistor is adhered to the surface of the hollow cavity of the spherical Langmuir probe; one end of the coaxial lead for supplying power to the temperature measuring resistor penetrates through hollow columnar spherical Langmuir probe bracket and is connected with the temperature measuring resistor, and the other end is connected with a temperature measuring power supply. The device can be used for effectively clean the spherical Langmuir probe when the satellite runs in the orbit during the satellite ion electric propulsion plume monitoring, and the device can be heated by consuming lower power.

The invention provides a Langmuir probe, a Langmuir probe detection system and a detection method, and relates to the electric thruster vacuum plume parameter detection equipment technology field. A probe, a limiting shell, a sliding inner shell and a rotating shaft are included. A first end of the probe is stretched out of the first end of the sliding inner shell, and a second end is connected with a rotating shaft. The limiting shell is fixed, the first end of the sliding inner shell is stretched out of the first end of the limiting shell, and the limiting shell limits the sliding inner shell to rotate around an axial direction. An inner side wall of the sliding inner shell is in threaded connection with an outer side wall of the rotating shaft. The rotating shaft is rotated to drive thesliding inner shell to slide relative to the limiting shell along the axial direction. In the invention, a length of the probe can be changed without moving the probe, accuracy of a position of the probe is ensured, space precision is ensured, an interference is not brought to a flow field, and measurement accuracy is improved.

The invention discloses a Langmuir probe, a Langmuir probe diagnosis system and a diagnosis method thereof, which relate to the technical field of plasmas. The Langmuir probe comprises a collector, aconductive screw lead, a ceramic sheath and a nut, wherein the collector comprises a first cylindrical sub collector and a second cylindrical sub collector; the diameter of the first sub collector islarger than that of the second sub collector, the first sub collector and the second sub collector have a concentric structure, and the first sub collector and the second sub collector are integrallyformed; the conductive screw lead is screwed to the second sub collector to be connected with the second sub collector; the ceramic sheath is boss-shaped and sleeves the side surface of the first subcollector and the side surface of the second sub collector and is in interference fit with the first sub collector and the second sub collector; and a hexagon nut is in screw joint with the conductivescrew lead and is in butt joint with the ceramic sheath. The Langmuir probe can prevent the side surface of the probe from gathering particles, the probe gathering area is reduced, and the measurement precision is improved.

The invention discloses a Verification method for a spacecraft suspension potential test including steps of setting up a space suspension potential measurement simulation test platform for the spacecraft, connecting the plasma generator housing on the test platform to the first contact of the three-state switch, adopting The second contact and the third contact of the three-state switch to form the charge loop and the discharge loop respectively. The plasma density and the capacitance voltage in the vacuum chamber are measured by the oscilloscope and the Langmuir probe electrically connectedwith the plasma generator housing to verify the change of the spacecraft floating potential in the space environment. The method of the invention can accurately and quickly judge the change of the floating potential of the spacecraft through a plurality of tests and actual measurements, and the test data obtained by using the measuring means of the oscilloscope and the Langmuir probe are true andaccurate.

The invention discloses a positive and negative amplitude-modulation pulse driven electrostatic probe and a data acquisition and analysis integrated device. After being amplified, a square wave pulse signal having an adjustable amplitude is used as the bias voltage of a Langmuir probe; a current signal acquisition system rapidly acquires current in a specific current acquisition point on each pulse bias voltage; then, the voltage is decreased to 0; after being naturally cooled, the probe applies and acquires the next pulse square wave; therefore, the self-heating effect of the probe is avoided; furthermore, a soft-switching technology and a large-range current measurement means are adopted in the current signal acquisition system; the precision disadvantage of micro-nano acquisition of ionic current is avoided; finally, after synchronous voltage signals and current signals are processed and calculated through a DSP data processing system, the parameters of the Langmuir probe, such as the V-I characteristic curve, the electronic temperature, the energy distribution, the electron density and the space potential, are obtained; and the parameters are conveniently displayed in an upper computer system.