58 results about "Gunn diode" patented technology

A monopulse vehicular radar system for tracking a target about an automotive vehicle senses a transmitted signal reflected back from the target and received at two different locations, determines the sum and the difference of the reflected signals sensed at the two locations, and compares the sum and difference to determine the deviation of the target from a reference azimuth. A source frequency provided by a Gunn diode is applied to and transmitted by a two-lobe monopulse antenna. The antenna lobes detect the reflected signals from the target by sensing them at the two different lobes. A hybrid junction provides sum and difference signals to mixers which homodyne the signals to produce sum and difference Doppler frequency signals using the source frequency. The Doppler frequency signals are amplified and then compared to determine the deviation of the target from the reference azimuth. The comparison process can be done digitally by converting the amplified frequency signals to digital signals which are then processed in a digital signal processor, or the comparison may be done in analog fashion using a phase / quotient detector. The range or distance of the target is determined by shifting the source frequency between two frequencies during transmission and frequency shifting the sum and difference Doppler frequency signals in similar fashion following reception by the antenna.

The invention discloses a terahertz GaN Gunn diode based on an SiC substrate and a manufacturing method thereof, which are used for mainly solving the problems of low output power, poor heat radiation performance and the like in the traditional Gunn device structure. The diode respectively comprises the SiC substrate, an AlN nucleating layer, an n+GaN ohmic contact layer, an electron emitting layer, an n-GaN active layer and an n+GaN ohmic contact layer from bottom to top and is characterized in that the electron emitting layer is made of an InAlN material with 14-22% of an In component and has the thickness of 80-200 nm; a through hole (1) is etched in the SiC substrate; metals Ti / Al / Ni / Au are deposited at the bottom of the substrate; and the metals are connected with an annular electrode (5) through the through hole, so that a longitudinal device structure is formed. The terahertz GaN Gunn diode disclosed by the invention is capable of eliminating a piezoelectric polarization effect and obviously reducing interface dislocation and the length of a Dead Zone, has the advantages of high output power and working frequency, and is applied to working in terahertz frequency bands.

The invention discloses a THz GaN Gunn diode structure based on a conduction-type SiC substrate and the fabrication method thereof, which mainly solve the problem of extremely low output power of a GaAs-based THz Gunn device. The THz GaN Gunn diode comprises a SiC substrate layer, an AlN nucleation layer, and a GaN epitaxial layer, wherein the SiC substrate layer has an n-type conduction-type structure with a doping concentration of 5times10cm to ensure low-resistance conductivity; the low-temperature AlN nucleation layer has a thickness of 30 to 50 nm so that the dislocation density in the GaN epitaxial layer is reduced; the lower layer of the GaN epitaxial layer is a heavily-doped nGaN layer with a doping concentration of 5times10cm and a thickness of 1 mum; the intermediate layer is a lightly-doped NGaN layer with a doping concentration of 1times10cm and a thickness of 1 to 3 mum; and the upper layer is a heavily-doped nGaN layer with a doping concentration of 5times10cm and a thickness of 100 nm. Two etching steps are adopted in the entire fabrication of the device to realize the metallization with two different properties of SiC ohmic contact and GaN ohmic contact metallation, thereby reducing the parasitic series resistance. The THz GaN Gunn diode structure has the advantages of high output power and work frequency, and suits operation in THz bands.

A high frequency oscillator has a substrate, a resonator circuit which is disposed on one principal surface of the substrate and consists of a closed loop-shaped slot line including an inner conductor and an outer conductor, an electric boundary point set on the slot line, a two-port negative resistance element for connecting between the inner conductor and outer conductor, and an output line electrically connected to the slot line. The electric boundary point is set by connecting, for example, a stub to the resonator circuit. The stub functions as an electrically short-circuited end or an electrically open end. A Gunn diode is preferably used for the negative resistance element, and inserted at a position of the slot line resonator circuit at which impedance matching is achieved.

A high-frequency oscillator that can tune oscillation characteristics is provided. A high-frequency oscillator includes a Gunn diode serving as a high-frequency oscillation element that generates high-frequency signals, a resonator connected to the Gunn diode, a varactor diode serving as a variable-capacitance element that is disposed on the resonator and changes a resonance frequency, and a bias supply circuit that is connected to the varactor diode and supplies a bias voltage applied in order to change a capacitance. The bias supply circuit includes a trimmable chip resistor serving as a pre-set variable resistor that regulates a bias voltage applied to the varactor diode. By regulating the resistance value of the trimmable chip resistor, it is possible to control the capacitance value of the varactor diode and tune oscillation characteristics to a desired state.

The present invention relates to measurement of conductivity, particularly to the noncontact measurement of the conductivity using a microwave. A microwave oscillated by an oscillator (110) using a Gunn diode is applied through an isolator (120), a circulator (130), and a horn antenna (140) to a silicon wafer (150). The isolator (120) is used for reducing the standing wave influencing the operation of the instrument. The reflected wave is received by the same horn antenna (140), detected by a detector (160) connected to the circulator (130), and outputted in the form of a voltage. The detector (160) produces an output voltage proportional to the square of the amplitude of an electric field. Since the amplitude of the reflected wave from a silicon wafer (150) is proportional to the absolute value of the reflectance, the output voltage is also proportional to the square of the absolute value of the reflectance. The reflectance is in a certain relationship with the conductivity, the conductivity of the silicon wafer (150) can be determined.

The invention relates to a terahertz wave generation device, which comprises a shell, an offset filter, a fixing piece, a supporting rod and a Gunn diode. A holding hole and a waveguide hole are arranged in the shell. The holding hole and the waveguide hole penetrate through the shell. The direction of the waveguide hole is perpendicular to the direction of the holding hole. The waveguide hole is communicated with the holding hole. The offset filter comprises a cap tray and an offset rod. The cap tray is disc-shaped, is held in the holding hole and divides the holding hole into a first holding part and a second holding part. One end of the offset rod is held in the first holding part and is connected with the central part of the cap tray. The Gunn diode comprises an anode and a cathode, wherein the anode is electrically connected with the anode of an external power supply through the offset filter, and the cathode is electrically connected with the cathode of the external power supply sequentially through the supporting rod, the fixing piece and the shell. The terahertz wave generation device has the advantages of smaller size and lower cost, and is suitable for medical application.

The invention discloses a GaN Gunn diode based on an AlGaN / GaN superlattice electron emission layer and a manufacturing method of the GaN Gunn diode. The GaN Gunn diode and the manufacturing method mainly aim at solving the problems that an existing Gunn device is low in power and poor in heat dissipation performance. The diode comprises a main part and an auxiliary part. The main part comprises a SiC substrate, an AlN nucleating layer, an n+GaN cathode ohmic contact layer, the electron emission layer, an n-GaN active layer and an n+GaN anode ohmic contact layer from bottom to top. The auxiliary part comprises an annular electrode, a substrate electrode, a circular electrode, a passivation layer, an open hole and a through hole. An AlGaN / GaN superlattice is adopted for the electron emission layer and has four to six cycles, the thickness of a GaN layer and the thickness of an AlGaN layer in each cycle both range from 10 nm to 20 nm, and an Al component in the AlGaN layer is linearly and gradually changed to 15% from 0% from bottom to top. The length of a dead zone can be remarkably reduced, dislocation concentration is reduced, and the GaN Gunn diode is suitable for terahertz frequency band work.

The present invention provides a diagnostic system for plasma processing, wherein the diagnostic system comprises a multi-modal resonator, a power source, a detector, and a controller. The controller is coupled to the power source and the detector and it is configured to provide a man-machine interface for performing several monitoring and controlling functions associated with the diagnostic system including: a Gunn diode voltage monitor, a Gunn diode current monitor, a varactor diode voltage monitor, a detector voltage monitor, a varactor voltage control, a varactor voltage sweep control, a resonance lock-on control, a graphical user control, and an electron density monitor. The diagnostic system can further provide a remote controller coupled to the controller and configured to provide a remote man-machine interface. The remote man-machine interface. The remote man-machine interface can provide a graphical user interface in order to permit remote control of the diagnostic system by an operator. In addition, the present invention provides several methods of controlling the diagnostic system in order to perform both monitor and control functions.

The invention discloses a Gunn diode, a preparation method and a power synthesis millimeter wave oscillator of the Gunn diode, belonging to the technical field of semiconductor devices. The Gunn diode sequentially comprises an integrated hear sink, a metal diode, a transition layer, a second contact layer, a top electrode and a gold thickening electrode from bottom to top. The preparation method comprises the following steps: growing a first contact layer, the transition layer and the second contact layer orderly on the semiconductor substrate, corroding a deep groove, evaporating the electrodes and electroplating the heat sink on the sample surface, removing the substrate, evaporating the top electrode, and conducting dry etching to form the Gunn diode. The millimeter wave oscillator seals the prepared Gunn diodes having good uniformity under a resonance cap in a waveguide cavity in pairs and at intervals of lambadag / 2. According to the method, the processing fragility of the material is reduced, the heat dissipation performance of the device is improved, and the device performance difference is reduced. The millimeter wave oscillator outputs the radio frequency after multiple Gunn diodes are coupled, so that the output power is increased by times.

An oscillation circuit is constructed by providing a line, a Gunn diode, and a dielectric resonator on a dielectric substrate; by disposing a dielectric stripline between upper and lower conductor plates to form an NRD guide which serves as a output transmission line; and the line and the NRD guide are coupled.

A Gunn diode having axis A consists of appropriately doped layers which, when a suitable voltage is applied, cause a space charge 6 to traverse a transit region 7 at a microwave frequency. In a typical known Gunn diode, the layers 4, 5 and 7 to 9 extend across the full diameter of the diode, and the space charge 6 is usually depicted as being disc-shaped. There is the disadvantage that the d.c. component of the Gunn effect current associated with a desired harmonic frequency causes undesirable heating. According to the invention, the area through which the current can flow through the elongate structure is tailored to favour the harmonic over the d.c. component, utilising the skin effect. Several ways of doing this are described, notably by making the core of the elongate portion non-conducting, for example, by ion implantation or by its removal by etching.

The present invention provides a small-sized oscillator facilitating the adjustment of a resonance frequency, permitting mass productivity to be improved, sufficiently suppressing a fundamental wave, and permitting cost reduction, and provides radio equipment using the oscillator. In this oscillator, an oscillation circuit is formed by providing a line and a Gunn diode on a dielectric substrate. An NRD guide serving as an output transmission line is formed by disposing a dielectric strip between upper and lower conductor plates, and the above-mentioned line and the NRD guide are coupled. The cut-off frequency of this NRD guide is determined so that the fundamental wave component of an oscillation signal from the oscillation circuit is cut off, so that higher harmonic components are propagated.

The invention discloses a GaN Gunn diode based on an AlGaN electro emission layer with bilinear-gradient Al components and a manufacturing method of the GaN Gunn diode. The GaN Gunn diode and the manufacturing method of the GaN Gunn diode mainly solve the problems that an existing Gunn device is low in output power and poor in heat dissipation performance. The diode comprises a main part and an auxiliary part. The main part comprises an SiC substrate, an AlN coring layer, an n+GaN cathode ohmic contact layer, an electro emission layer, an n-GaN active layer and an n+GaN anode ohmic contact layer from bottom to top and the auxiliary part comprises an annular electrode, a substrate electrode, a round electrode, a passivation layer, open holes and through holes, wherein the thickness of the electro emission layer is 200-600 nm, and the AlGaN structure with the bilinear-gradient Al components which are gradually changed linearly from 0% to 100% firstly and then from 100% to 0% from bottom to top is adopted. By means of the GaN Gunn diode and the manufacturing method of the GaN Gunn diode, the length of a dead zone can be obviously reduced, the dislocation concentration can be reduced and high-power output can be realized, and the GaN Gunn diode is suitable for working in the terahertz frequency range.

A soldering jig is disclosed. The soldering jig in accordance with an embodiment of the present invention includes: a mounting block having a plurality of accommodation holes penetrating from one surface to the other surface thereof, a plurality of soldered objects being accommodated in the plurality of accommodation holes; a first cover block coupled to one surface of the mounting block and having a support part configured to support the plurality of soldered objects accommodated in the plurality of accommodation holes; and a second cover block coupled to the other surface of the mounting block and having a plurality of pressing protrusions protruded to face the plurality of accommodation holes, respectively, to elastically support the plurality of soldered objects. Accordingly, a Gunn diode package that is soldered in a uniform quality can be obtained by maintaining a uniform pressure and heat transfer to the soldered objects in a soldering process.

The invention relates to a high-power and low-noise planar Gunn diode and a preparation method thereof. The high-power and low-noise planar Gunn diode comprises an insulation substrate, a channel layer, and a coplanar waveguide arranged above the channel layer, the length of a resonant cavity of the coplanar waveguide is integer multiples of one half of the resonance wavelength, and the characteristic impedance of the coplanar waveguide and the impedance (usually 50 ohm) of a load are the same with the resonant frequency. The planar Gunn diode is arranged in the resonant cavity of the coplanar waveguide so that the planar Gunn device can operate in a resonance mode, the emission power, the conversion efficiency and the frequency stability of the planar Gunn device are greatly improved, and the phase noise is reduced.

The invention discloses a GaN Gunn diode based on a notch structure and a manufacturing method for the GaN Gunn diode, and mainly solves problems of high dislocation concentration and poor heat dissipation property of a transition layer in an existing Gunn device. The diode adopts a multilayer structure comprising a SiC substrate, an AlN nucleating layer, a lower n<+>GaN cathode ohmic contact layer, an AlGaN electron emission layer, an upper n<+>GaN cathode ohmic contact layer, a GaN notch layer, an n<->GaN transition layer and an n<+>GaN anode ohmic contact layer from bottom to top; the percentage of an Al component is increased to 20% from 0% in a linear gradient manner from bottom to top; an annular electrode and a substrate electrode are arranged above the lower n<+>GaN cathode ohmic contact layer and below the SiC substrate; a round electrode is arranged above the n<+>GaN anode ohmic contact layer; a passivation layer is arranged above the annular electrode and the round electrode. The diode can remarkably reduce the dislocation concentration and the length of a dead region, and is suitable for working within a terahertz frequency range.

The invention provides an electronic magnetometer and a magnetic field measuring method. The magnetic field measuring method comprises: different induction high frequency oscillation currents are generated through a magnetic field in the environment having a Gunn diode with magnetic shielding and a magnetic field in the environment having a Gunn diode without magnetic shielding; and making a comparison by setting a circuit in the shielded Gunn diode high frequency current and in the unshielded Gunn diode high frequency oscillation current, the difference on the frequency between the two currents has proportional relation with the size of the magnetic field so that the size of the magnetic field can be obtained.

The invention relates to the technical field of diodes in microwave devices, in particular to a gunn diode and a manufacture method thereof. An epitaxial wafer of the gunn diode sequentially comprises a semiconductor insulating GaAs substrate, a heavily doped lower bottom surface n+GaAs layer, an active area n-GaAs layer, an nsGaAs layer, a GaAs intrinsic lower isolation layer, an Alx Ga1-xAs intrinsic barrier layer, a GaAs intrinsic upper isolation layer and a heavily doped upper surface n+GaAs layer from bottom to top. According to the gunn diode provided by the invention, dead areas in the active area n-GaAs layer can be effectively reduced, the conversion efficiency from direct current signals to radio frequency signals is increased, the thermal stability is improved; and output oscillation frequency and power are tuned by utilizing direct current voltage. The manufacture method of the gunn diode provided by the invention is simple, convenient and easy to realize single chip integration.

An oscillator, a dielectric waveguide device and a transmitter incorporating the same, wherein a special temperature-compensating circuit provides a temperature-compensated device with reduced size and cost, and greater productivity. In the oscillator, a dielectric plate having a strip line of a specified length is arranged between conductive plates which enclose a Gunn diode. The oscillation output signal of the Gunn diode is extracted via the strip line. In addition, the sign of the dielectric-constant temperature coefficient of the dielectric plate is set such that changes in the oscillation frequency caused by changes in temperature of the Gunn diode are suppressed.

The invention discloses a reinforced linear gradient doped GaAs planar Gunn diode, which comprises a semiconductor insulated substrate, a high doped bottom N+ layer, a linear gradient doped N layer, an N- layer, a high doped upper surface N+ layer, a table top structure, an upper electrode and a lower electrode, wherein the semiconductor insulated substrate is used for supporting the whole GaAs planar Gunn diode; the high doped bottom N+ layer is epitaxially grown on the semiconductor insulated substrate; the linear gradient doped N layer is continuously epitaxially grown on the bottom N+ layer; the N- layer is epitaxially grown on the linear gradient doped N layer; the high doped upper surface N+ layer is epitaxially grown on the N- layer; the table top structure is formed on the bottom N+ layer and the upper surface N+ layer by two processes of digging and isolating; the upper electrode of ohmic contact is formed by evaporating metal on the upper surface N+ layer; and the lower electrode of ohmic contact is formed by evaporating metal on the bottom N+ layer. The invention discloses a manufacturing method for the reinforced linear gradient doped GaAs planar Gunn diode at the same time. By using the diode, the working frequency of an oscillating circuit in a millimeter wave or sub millimeter wave range is improved, and the conversion efficiency of direct current-to-radio frequency signals is enhanced.

The present invention provides a diagnostic system for plasma processing, wherein the diagnostic system comprises a multi-modal resonator, a power source, a detector, and a controller. The controller is coupled to the power source and the detector and it is configured to provide a man-machine interface for performing several monitoring and controlling functions associated with the diagnostic system including: a Gunn diode voltage monitor, a Gunn diode current monitor, a varactor diode voltage monitor, a detector voltage monitor, a varactor voltage control, a varactor voltage sweep control, a resonance lock-on control, a graphical user control, and an electron density monitor. The diagnostic system can further provide a remote controller coupled to the controller and configured to provide a remote man-machine interface. The remote man-machine interface. The remote man-machine interface can provide a graphical user interface in order to permit remote control of the diagnostic system by an operator. In addition, the present invention provides several methods of controlling the diagnostic system in order to perform both monitor and control functions.

The invention relates to a high-power and low-noise planar Gunn diode and a preparation method thereof. The high-power and low-noise planar Gunn diode comprises an insulation substrate, a channel layer, and a coplanar waveguide arranged above the channel layer, the length of a resonant cavity of the coplanar waveguide is integer multiples of one half of the resonance wavelength, and the characteristic impedance of the coplanar waveguide and the impedance (usually 50 ohm) of a load are the same with the resonant frequency. The planar Gunn diode is arranged in the resonant cavity of the coplanar waveguide so that the planar Gunn device can operate in a resonance mode, the emission power, the conversion efficiency and the frequency stability of the planar Gunn device are greatly improved, and the phase noise is reduced.

The invention discloses a ka-band monolithic integrated voltage-controlled oscillator based on a plane gunn diode. The ka-band monolithic integrated voltage-controlled oscillator is characterized by comprising a direct current bias voltage input unit, an input lowpass filter, an output interpolation coupling capacitor, the plane gunn diode with a hot electron injection effect and a resonator which are connected in sequence. A direct current bias voltage is fed from a middle conductor of the direct current bias voltage input unit and is fed by connecting a central microstrip line of the input lowpass filter and an upper end metal arm of the output interpolation coupling capacitor with one end of a top layer anode of the plane gunn diode with the hot electron injection effect. According to the ka-band monolithic integrated voltage-controlled oscillator, a monolithic microwave integrated circuit and coplanar waveguide technology is employed; a self-bias circuit structure is employed; a circuit structure is simple; monolithic integration is easy to realize; and a complicated cavity waveguide packaging assembly is unnecessary. According to the ka-band monolithic integrated voltage-controlled oscillator, the plane gunn diode with the hot electron injection effect is introduced, so that the direct current-radio frequency conversion efficiency of the voltage-controlled oscillator is effectively enhanced.

The invention discloses a linear gradient doped GaAs planar gunn diode which comprises a semiconductor insulating substrate, a highly doped lower bottom surface N<+> layer, a linear gradient doped N<-> type layer, a heavily doped upper surface N<+> layer, a table-board structure, an upper electrode and a lower electrode, wherein the semiconductor insulating substrate is used for supporting the whole GaAs planar gunn diode; the highly doped lower bottom surface N<+> layer epitaxially grows on the semiconductor insulating substrate; the linear gradient doped N<-> type layer epitaxially grows on the lower bottom surface N<+> layer; the upper surface N<+> layer epitaxially grows on the linear gradient doped N<-> type layer; the table-board structure is formed on the upper surface N<+> layer and the lower bottom surface N<+> layer through an island digging and insulating; the upper electrode in an ohmic contact is formed on the upper surface N<+> layer by metal evaporation; and the lower electrode in an ohmic contact is formed on the lower bottom surface N<+> layer by metal evaporation. The invention also discloses a method for manufacturing the linear gradient doped GaAs planar gunn diode. By utilizing the linear gradient doped GaAs planar gunn diode, the working frequency of oscillating circuits within the ranges of millimeter waves and submillimeter waves is increased, and the conversion efficiency from direct current to ratio frequency is enhanced.

A high-frequency oscillator that can tune oscillation characteristics is provided. A high-frequency oscillator includes a Gunn diode serving as a high-frequency oscillation element that generates high-frequency signals, a resonator connected to the Gunn diode, a varactor diode serving as a variable-capacitance element that is disposed on the resonator and changes a resonance frequency, and a bias supply circuit that is connected to the varactor diode and supplies a bias voltage applied in order to change a capacitance. The bias supply circuit includes a trimmable chip resistor serving as a pre-set variable resistor that regulates a bias voltage applied to the varactor diode. By regulating the resistance value of the trimmable chip resistor, it is possible to control the capacitance value of the varactor diode and tune oscillation characteristics to a desired state.

The invention solves a problem of a non-invasive effect on a biological object for suppressing in it and in its biological substances of pathological factors (pathogenic microorganisms and processes) and / or for stimulating of the biological activity of biological objects and biological substances which constitute the biological object.The device includes a power source connected to a semiconductor device, the active layer of which contains a semiconductor structure based on A3B5 compound. The A3B5 semiconductor device is made with a volt-ampere characteristic having a section with a negative differential conductance, the value of which exceeds the differential conductance of the biological object. The semiconductor device may be made as the Gunn diode, as the tunnel diode, as the BARRIT diode and as the transistor. The semiconductor structure may be made, at least, with two working volumes of the same or diverse A3B5 compounds with different geometrical dimensions.

The invention relates to the technical field of diodes in microwave devices, in particular to a gunn diode and a manufacture method thereof. An epitaxial wafer of the gunn diode sequentially comprises a semiconductor insulating GaAs substrate, a heavily doped lower bottom surface n+GaAs layer, an active area n-GaAs layer, an nsGaAs layer, a GaAs intrinsic lower isolation layer, an Alx Ga1-xAs intrinsic barrier layer, a GaAs intrinsic upper isolation layer and a heavily doped upper surface n+GaAs layer from bottom to top. According to the gunn diode provided by the invention, dead areas in the active area n-GaAs layer can be effectively reduced, the conversion efficiency from direct current signals to radio frequency signals is increased, the thermal stability is improved; and output oscillation frequency and power are tuned by utilizing direct current voltage. The manufacture method of the gunn diode provided by the invention is simple, convenient and easy to realize single chip integration.

The invention relates to a Terahertz GaN Gunn diode and a manufacturing method thereof. The Terahertz GaN Gunn diode comprises a cathode, an n type GaN substrate, an n+ GaN cathode ohmic contact layer, an InAlN three-dimensional structure electronic emission layer, an n-GaN transition layer, an n+ GaN anode ohmic contact layer, and an anode which are successively arranged from bottom to top, and also comprises an SiN passivation layer arranged on the n type GaN substrate, and covering the n+ GaN cathode ohmic contact layer, the InAlN three-dimensional structure electronic emission layer, the n-GaN transition layer, the n+ GaN anode ohmic contact layer, and the anode; the upper portion of the SiN passivation layer is provided with an open pore exposing the anode. The Terahertz GaN Gunn diode employs a three-dimensional structure InAlN electric emission layer structure, and substantially increases the output power density of a GaN Gunn diode under a same size.