43results about How to "Reduce RF loss" patented technology

The invention discloses a heterojunction bipolar transistor structure and a manufacturing method thereof. The method comprises the following steps: carrying out etching on a semiconductor device withemitter contact metal to etch off a cap layer around the emitter contact position and retain the cap layer under the emitter contact position and around the semiconductor device; depositing a first protection layer; etching the base contact position to etch off the first protection layer and an emitter layer on the base contact position; depositing base contact metal at the base contact position;depositing a second protection layer; etching the base table position to etch off the second protection layer, the first protection layer, the emitter layer, the base layer and a part of collector layer around the base table position and retain the structure around the semiconductor device. The scheme can avoid generation of arrow shadow, improve product yield rate and reduce parasitic capacitance, thereby reducing radio frequency loss.

The invention discloses a silicon on insulator (SOI) process-based back gate drain/source semi-floating front gate power-metal-oxide-semiconductor field effect transistor (P-MOSFET) radio frequency switch zero loss device. A drain/source region of a silicon on insulator P-channel metal oxide semiconductor (SOI PMOS) device is transformed, and the junction depth of a source (or drain) region is set to be slightly smaller than the thickness of N-type top silicon, namely an N-type channel region; the back gate drain semi-floating is taken as an example, the junction depth of a source region is deeper, the junction depth of the drain region is set to be slightly smaller than the thickness of P-type top silicon, a parasitic diode is formed, direct current signals applied to a drain electrode are isolated, and by offsetting a body and a back gate, a back gate MOSFET channel is switched-on; according to the structure, impedence under the on state of a front gate MOSFET is adjusted, the radio frequency loss of the front gate MOSFET serving as a switch under the on state is reduced, and even a zero loss radio frequency switch is formed; when the self-heating effect of the device is generated to cause negative impedence of the back gate MOSFET, or when the back gate MOSFET works in an amplification state, a front gate coupling signal can be directly amplified, and energy loss of the front gate under the on state is compensated, so that an ultralow and zero loss radio frequency switch is formed.

The invention provides a shortwave antenna tuning insertion loss test fixture comprising a vector network analyzer, a measurement and control computer, a radio frequency conversion switch K1 and tested antenna tuning and an antenna, wherein the measurement and control computer is connected with a vector network, the tested antenna tuning and the radio frequency conversion switch K1 through a serial port or a network port, the K1 communicates the tested antenna tuning 1 on an antenna port 2 at a first position, namely the connects the tested antenna tuning to the tested antenna; the K1 communicates the antenna port 2 with a vector network port at a second position, namely connects the tested antenna to the vector network port; and an output end of the measurement and control computer controls a control switch K1 and the tested antenna tuning.

The invention provides a communication device and a terminal, which relate to the technical field of communication devices. The communication device comprises antenna modules, a control circuit and acircuit board, wherein the control circuit comprises a main control chip and control chips; the antenna modules are arranged on the first face of the circuit board, and the main control chip and the control chips are arranged on the second face of the circuit board; the main control chip is electrically connected with the control chips; the antenna modules and the control chips are electrically connected through via holes in the circuit board; and the control chips are used for controlling the antenna modules to transmit and receive signals according to an instruction of the main control chip.Through arranging the control circuit and the antenna modules in the communication device on two faces of the circuit board, the space occupied by the antenna modules and the control circuit is further saved. As the antenna modules and the control circuit are arranged on the circuit board, the paths between the antenna modules and the control circuit are reduced, the space is saved, the difference loss of radio frequency can be further reduced, and the radio frequency performance of the antenna module is improved.

The invention discloses a back grid drain/source self-floating front grid N-MOSFET radio frequency switch zero-loss device based on the SOI technology. A drain area or a source area of an SOIPMOS device is transformed, the junction depth of the source area or the drain area is set to be slightly smaller than the thickness of P-type top layer silicon, the back grid drain semi-floatation serves as an example, the junction depth of the source area is large, the junction depth of the drain area is slightly smaller than the thickness of the P-type top layer silicon, a parasitic diode is formed, then isolation of a direct current signal is applied to a drain electrode, and a back grid MOSFET channel enters the conducting state due to biasing of a body grid and the back grid; as the back grid MOSFET operates in the conducting state, the impedance generated when a front grid MOSFET is located in the conducting state is adjusted, the radio frequency loss caused when a front grid N-MOSFET serves as a switch and is applied in the switch-on state is reduced, and even a zero-loss radio frequency switch is formed. When the self-heating effect of the device is generated and negative impedance of the back grid MOSFET is formed, or when the back grid MOSFET operates in an amplification state, coupling signals of the front grid can be directly amplified, energy losses caused when the front grid is in the opening state can be compensated, and the ultralow or zero loss radio frequency switch is formed.

The invention provides a composite substrate, a composite film, a preparation method of the composite film and a radio frequency surface acoustic wave device. The composite substrate sequentially comprises a substrate layer and a polycrystalline layer from bottom to top, wherein the polycrystalline layer comprises a crystal grain gradient layer and a crystal grain uniform layer; crystal grains in the crystal grain gradient layer are of a columnar structure, and the crystal grains of the columnar structure are gradually increased in the direction from the substrate layer to the crystal grain uniform layer. The grain gradient layer grows on the substrate layer, columnar grains in the grain gradient layer are sufficient in density, meanwhile, large stress generated after high-temperature cooling of the grain uniform layer can be dispersed, and interlayer gaps generated by chemical bond breakage due to the fact that the large stress acts on the substrate layer and the grain uniform layer are avoided; the surface, close to the substrate layer, of the crystal grain uniform layer is provided with dense carrier traps, and the effect of limiting carrier movement is enhanced, so that the interface resistivity is improved, the radio frequency loss of the radio frequency surface acoustic wave device is reduced, and the performance of the radio frequency surface acoustic wave device is improved.

The invention discloses a method for preparing a GaN-based electronic device. The method comprises the steps: carrying out doping treatment on the surface of a high-resistance substrate to make any one or more of vacant sites, gap sites and replacement sites on the surface of the high-resistance substrate be occupied by doping ions and/or doping atoms, so that external Al atoms and/or Ga atoms can be prevented from diffusing into the high-resistance substrate or parasitic conduction is inhibited by using a compensation mechanism; then growing an epitaxial structure containing Al atoms and/or Ga atoms on the surface of the high-resistance substrate; and manufacturing a GaN-based electronic device based on the epitaxial structure. The invention also discloses a GaN-based electronic device prepared by using the method. According to the invention, the manufacturing method of the GaN-based electronic device is simple and effective, the crystal quality of the epitaxial layer can be guaranteed, and the problems of secondary epitaxial interface impurity contamination, low production efficiency and the like are solved, so that the GaN-based radio frequency microwave device epitaxial wafer with low radio frequency loss and high performance can be manufactured.

The invention relates to an antenna and a mobile terminal. The antenna comprises a feed end, a first radiator, a second radiator and a gap located between the first radiator and the second radiator. The feed end is electrically connected with the first radiator or the second radiator and provides a feed signal for the first radiator or the second radiator; the first radiator and/or the second radiator are/is part of a metal frame of the mobile terminal. According to the antenna, the space of the mobile terminal can be effectively saved, and the isolation between the antenna and other structures of the mobile terminal is improved.

The invention relates to a Si-based AlGaN/GaN HEMT based on a wrapping buried layer and a diffusion barrier layer and a preparation method. The Si-based AlGaN/GaN HEMT comprises a Si substrate, the diffusion barrier layer, an AlN nucleating layer, an AlGaN order change layer, a GaN buffer layer and an AlGaN barrier layer which are stacked in sequence, an N-type buried layer and an isolation layer are arranged in the Si substrate, and the isolation layer is arranged between the Si substrate and the N-type buried layer and wraps the N-type buried layer. According to the AlGaN/GaN HEMT, an N-type buried layer and an isolation layer are arranged in a Si substrate, the isolation layer cannot completely mask N-type impurities in the N-type buried layer, and the N-type impurities can be diffused into the Si substrate so that the concentration of a P-type channel introduced into the Si substrate by diffusion of Al in an upper layer structure is counteracted, the resistivity of the substrate is improved, and the radio frequency loss of a device is reduced; and meanwhile, the diffusion barrier layer is arranged between the Si substrate and the AlN nucleating layer, and the diffusion barrier layer can achieve the effect of blocking diffusion of Al atoms so that P-type conductive doping in the substrate is reduced, the resistivity of the substrate is improved, and then the radio frequency loss of the substrate is reduced.

The invention relates to the technical field of semiconductors, in particular to a low-loss gallium nitride radio frequency material epitaxial structure and a preparation method. A buffer layer, a gallium nitride channel layer, an N-type low-doped gallium nitride layer, a barrier layer and an amide cap layer epitaxially grow on a silicon substrate in sequence to obtain the low-loss gallium nitrideradio frequency material epitaxial structure. According to the invention, the N-type low-doped gallium nitride layer is added below the barrier layer, and the square resistance of the N-type low-doped gallium nitride layer is lower than that of two-dimensional electron gas, so that the N-type low-doped gallium nitride layer has a very weak function of participating in conduction under a normal on-state condition, but in the process from an off state to an on stage, electrons of the N-type low-doped gallium nitride layer can supplement the reduction of the concentration of two-dimensional electron gas; secondly, electrons transferred back to a heterojunction interface from the buffer layer can quickly pass through the N-type low-doped gallium nitride layer, so that the effect of quickly supplementing two-dimensional electron gas of the heterojunction interface is achieved; and therefore, the concentration of the two-dimensional electron gas in the dynamic process can be reduced to themaximum extent by adding the N-type low-doped gallium nitride layer, so that the radio frequency loss is reduced.

The invention provides a composite substrate and a preparation method thereof and an electronic component, and the composite substrate sequentially comprises a substrate layer, a polycrystalline layer, an insulating layer and a thin film layer from the bottom to the top. The polycrystalline layer is provided with a crystal grain cluster composed of two or more crystal grains. According to the scheme, the polycrystalline layer with the grain cluster structure is arranged between the insulating layer and the substrate layer, a large number of defects formed in the grain cluster can capture charged carriers, the carriers are gathered at the grain boundary to form a potential barrier between grains, movement of the carriers between the grains is limited, and therefore, the interface conductionbetween the insulating layer and the semiconductor layer can be reduced, and the radio frequency loss is reduced.

The invention discloses a Si-based GaN millimeter wave transmission line structure and a preparation method. The Si-based GaN millimeter wave transmission line structure comprises a Si substrate; an AlN nucleating layer, arranged on the Si substrate; a III-nitride transition layer, arranged on the AlN nucleating layer; a GaN buffer layer, arranged on the III-nitride transition layer; a metal ground layer over the GaN buffer layer; a dielectric insertion layer over the metal formation; a CPW over the dielectric insertion layer; and a ground wire of the CPW connected with the metal ground layerthrough the through hole in the medium insertion layer. The objective of the structure is to solve the problem of high radio frequency loss of a transmission line in millimeter wave circuit application. The invention provides a millimeter wave application-oriented transmission line structure on a Si-based GaN structure and a preparation method. A layer of metal ground is inserted between a CPW anda GaN layer to shield the influence of a p-type conducting channel at an AlN/Si interface, so that the radio frequency loss of the transmission line is reduced, and the application requirement of thetransmission line in a millimeter wave circuit is met.