Carrier plate type microwave power amplifier capable of being tested on chip
Technical Field
The invention relates to a carrier plate type microwave power amplifier, in particular to a carrier plate type microwave power amplifier capable of being tested on a chip.
Background
At present, when a GaN (gallium nitride) and GaAs (gallium arsenide) microwave power amplifier chip is used, a peripheral circuit generally adopts a molybdenum copper or diamond copper carrier plate as a carrier plate larger than the chip, the power amplifier chip is eutectic, a plurality of chip capacitors are added to form a secondarily packaged power amplifier module, input/output and power-on parts are led out by adopting copper sheets or pins made of other materials, and then the power amplifier module is installed in an assembly for assembly and application. The problem with such an application is that: because a large capacitance is required at the periphery of a chip in the application process of GaN (gallium nitride) and GaAs (gallium arsenide) microwave power amplifier chips, the inside of the package does not have the consideration, and the chip has great risk of resisting external power-on impact and is easy to generate self-excited burning when the chip is not well processed.
There are also two problems that may exist with pin extraction after secondary packaging: firstly, the assembly mode is integrated with the assembly only by adopting brazing, so that the development of a micro-assembly process is not facilitated, the pollution in the brazing process is also not facilitated, the miniaturization of the assembly is also facilitated, and the detailed structure is shown in figure 1; secondly, in the integration process, the pins are bent in the welding process due to the height difference inside the assembly, so that the input and output standing waves of the power amplifier chip are deteriorated, the output power is reduced, even the bending can cause the breakage of the power amplifier pins to cause the failure of the device, and the detailed structure is shown in fig. 2; thirdly, if the packaged power amplifier is used for carrying out the advanced screening test of the device, a relatively complex tooling fixture (a specially designed polytetrafluoroethylene pressing block is used for installing a flange and a pin of the packaged power amplifier on a metal cavity of the fixture by a screw to press the device) is required to be designed, the working efficiency is low, the pin damage rate is high in the screening process, and the detailed assembly fixture is shown in fig. 3.
Disclosure of Invention
The invention aims to improve the reliability of GaN (gallium nitride) and GaAs (gallium arsenide) microwave power amplifier chips in power amplifier components, TR components or other high-power microwave components, and therefore provides a carrier plate type microwave power amplifier capable of being tested on a chip.
A carrier plate type microwave power amplifier capable of being tested on a chip comprises an input circuit chip, an output circuit chip, a microwave power amplification chip and a power supply filter circuit chip which are integrated on a carrier plate; the output circuit piece and the output circuit piece are connected with a coplanar waveguide in parallel;
the power supply filter circuit chip is connected with the output circuit chip;
the input circuit piece and the output circuit piece are connected with a microwave power amplification chip.
Preferably, the carrier plate type microwave power amplifier capable of being tested on chip further comprises a plurality of chip capacitors, one end of one part of the chip capacitors is connected with a gate bias voltage pin of the microwave power amplification chip, and the other end of the chip capacitors is connected with a gate of the input circuit chip; one end of the other part of the chip capacitor is connected with a drain electrode bias voltage pin of the microwave power amplification chip, and the other end of the chip capacitor is connected with the power supply filter circuit chip; the chip capacitor mainly plays a role in decoupling and filtering, and the stability of the power amplifier is improved.
Preferably, one end of a part of the chip capacitor is connected with a gate bias voltage pin of the microwave power amplification chip by a gold wire, and the other end of the chip capacitor is connected with a gate of the input circuit chip by a gold belt; one end of the other part of the chip capacitor is connected with a drain electrode bias voltage pin of the microwave power amplification chip by a gold wire, and the other end of the chip capacitor is connected with the power supply filter circuit chip by a gold belt; the gold belt is commonly used for interconnection of the capacitor, the ceramic chip and other non-chip bonding pads, the chip capacitor and the grid electrode of the input circuit chip are interconnected by the gold belt, the chip capacitor and the drain electrode of the output circuit chip are interconnected by the gold belt, the distance span requirement between components is met, the reliability of the gold belt is higher, and the gold belt is more difficult to collapse compared with a gold wire; the gold wire is commonly used for leading out an internal bonding pad of the chip, an external radio frequency input/output pad, a power supply bonding pad and the like, and the gold wire is used for interconnection, so that the conductivity is high, and the corrosion resistance and the toughness are good.
Preferably, the grids inside the input circuit chip are interconnected through gold wires or gold strips; and the drains in the output circuit chip are also interconnected through gold wires or gold belts.
Preferably, the input end of the input circuit chip is connected with the signal input end pin of the microwave power amplification chip through a gold wire; and the output end of the input circuit chip is connected with the signal output end pin of the microwave power amplification chip through a gold wire.
Preferably, the carrier plate is molybdenum-copper alloy or diamond copper, the carrier plate needs to use a material with a thermal expansion coefficient close to that of the carrier plate, high thermal conductivity and high electric conductivity, the molybdenum-copper alloy adopts high-quality molybdenum powder and oxygen-free copper powder, and the carrier plate is formed by isostatic pressing, so that the structure is fine and dense, the arc breaking performance is good, the electric conductivity is good, and the thermal expansion is small; the diamond copper material, namely the diamond particle reinforced copper-based composite material has the thermal conductivity far higher than that of the traditional WCu, MoCu and SiC/Al materials, the thermal expansion coefficient can be adjusted to be matched with a semiconductor chip or a ceramic substrate by controlling the volume content of diamond, and the bending strength is higher than that of oxygen-free copper; the molybdenum-copper alloy or diamond-copper is selected as the carrier plate to meet the actual requirement.
Preferably, the microwave power amplification chip is a GaN or GaAs chip, and the GaN or GaAs chip is used to output a large microwave power, generally more than 1W, tens, hundreds of watts or even higher.
Preferably, the input pad, the output pad and the power-up pad of the microwave power amplification chip are all gold wire pressure point pads.
Preferably, there are two power filter circuit pieces, and the power filter circuit pieces are respectively connected with the drain electrodes of the output circuit pieces by gold bands; the power supply filter circuit chip is mainly used for drain power supply filtering.
Preferably, one of the coplanar waveguides is connected in parallel between the gate of the input circuit chip and the input signal terminal; one coplanar waveguide is connected in parallel between the drain electrode of the output circuit chip and the output signal end; the coplanar waveguide part is added on the input circuit chip and the output circuit chip, so that on-chip test can be performed on a probe station.
Compared with the prior art, the beneficial effects of adopting the technical scheme are as follows: the coplanar waveguide suitable for the testing arm of the probe station is designed on the input circuit chip and the output circuit chip, so that the carrier plate type microwave power amplifier can be screened by adopting a special clamp, the carrier plate is arranged on a metal clamp by using a screw, and then the gold belt is bonded for carrying out clamp testing, and also can be directly arranged on the probe station for carrying out testing through a mechanical part on the probe station; secondly, the device and the peripheral circuit are integrally miniaturized, the carrier plate can be made smaller as required, the carrier plate type power amplifier made in the way can be directly integrated in the component, the peripheral circuit requirement is not high, and the design risk of a user can be reduced.
Drawings
FIG. 1 shows a peripheral circuit of a 2.5-6GHz 30W power amplifier package of a typical power amplifier in foreign countries.
FIG. 2 is a topological diagram of an internal circuit of a peripheral circuit of a typical power amplifier 2.5-6GHz 30W power amplifier package at abroad.
Fig. 3 is a typical power amplifier screening test fixture in foreign countries.
Fig. 4 is an assembly diagram of a carrier-board microwave power amplifier chip according to the present invention.
Fig. 5 is a coplanar waveguide structure in the input die and the output die of fig. 4.
In fig. 4: 1-1-power filter circuit chip I, 1-2-power filter circuit chip II, 2-1-input circuit chip, 2-2-output circuit chip, 3-carrier plate, 4-microwave power amplification chip, 5-1-chip capacitor I, 5-2-chip capacitor II, 5-3-chip capacitor III, 6-1-chip capacitor IV, 6-2-chip capacitor V, 7-gold wire, 8-gold strip I, 9-gold strip II, 10-test point, 11-grid power supply end I, 12-radio frequency signal input end, 13-grid power supply end II, 14-drain power supply end I, 15-radio frequency signal output end, 16-drain power supply end II, 17-coplanar waveguide.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
As shown in fig. 4-5.
A carrier plate type microwave power amplifier capable of being tested on a chip comprises an input circuit chip 2-1, an output circuit chip 2-2, a microwave power amplification chip 4 and a power supply filter circuit chip which are integrated on a carrier plate; the input circuit chip 2-1 and the output circuit chip 2-2 are both connected with a coplanar waveguide 17 in parallel;
the power supply filter circuit chip is connected with the output circuit chip 2-2;
the input circuit chip 2-1 and the output circuit chip 2-2 are connected with a microwave power amplification chip 4.
The carrier plate type microwave power amplifier capable of being tested on chip also comprises a plurality of chip capacitors, one end of one part of the chip capacitors is connected with a grid bias voltage pin of the microwave power amplification chip 4, and the other end of the chip capacitors is connected with a grid of the input circuit chip 2-1; one end of the other part of the chip capacitor is connected with a drain bias voltage pin of the microwave power amplification chip 4, and the other end of the chip capacitor is connected with the power supply filter circuit chip; the chip capacitor mainly plays a role in decoupling and filtering, and the stability of the power amplifier is improved.
One end of a chip capacitor I5-1 and one end of a chip capacitor II 5-2 are connected with a grid bias voltage pin of the microwave power amplification chip 4, and the other end of the chip capacitor I5-1 is connected with a grid of the input circuit chip 2-1; one end of the chip capacitor III 6-1 and one end of the chip capacitor IV 6-2 are connected with a drain electrode bias voltage pin of the microwave power amplification chip 4, and the other end of the chip capacitor III is connected with the power supply filter circuit chip.
One end of one part of the chip capacitor is connected with a grid bias voltage pin of the microwave power amplification chip 4 by a gold wire, and the other end of the chip capacitor is connected with a grid of the input circuit chip 2-1 by a gold belt; one end of the other part of the chip capacitor is connected with a drain electrode bias voltage pin of the microwave power amplification chip 4 by a gold wire 7, and the other end of the chip capacitor is connected with the power supply filter circuit chip by a gold belt; the gold belt is commonly used for interconnection of the capacitor, the ceramic chip and other non-chip bonding pads, the chip capacitor and the grid electrode of the input circuit chip are interconnected by the gold belt, the chip capacitor and the drain electrode of the output circuit chip are interconnected by the gold belt, the distance span requirement between components is met, the reliability of the gold belt is higher, and the gold belt is more difficult to collapse compared with a gold wire; the gold wire is commonly used for leading out an internal bonding pad of the chip, an external radio frequency input/output pad, a power supply bonding pad and the like, and the gold wire is used for interconnection, so that the conductivity is high, and the corrosion resistance and the toughness are good.
One end of the first chip capacitor 5-1 and one end of the second chip capacitor 5-2 are connected with a gate bias voltage pin of the microwave power amplification chip 4 by a gold wire 7, and the other end of the first chip capacitor is connected with a gate of the input circuit chip 2-1 by a gold strip 8; one end of the chip capacitor III 6-1 and one end of the chip capacitor IV 6-2 are connected with a drain electrode bias voltage pin of the microwave power amplification chip 4 by a gold wire 7, and the other end of the chip capacitor III is connected with the power supply filter circuit chip by a gold strip II 9.
It should be noted that, the gold wire for direct chip interconnection is generally 18um or 25um, but is not limited to this value.
It should be noted that the sizes of the chip capacitor one 5-1, the chip capacitor two 5-2 and the chip capacitor three 5-3 are small, the sizes are about 0.7mm x 0.7mm, and the capacitance values are generally 100pF and 330pF, but not limited to this capacitance value.
It should be noted that, the size of the chip capacitor three 6-1 and the size of the chip capacitor four 6-2 are larger, the sizes are about 1mm × 1mm, and the capacitance value is generally 1000pF, but not limited to this capacitance value.
The grids in the input circuit chip are interconnected through a gold wire 7 or a gold belt 8; and the drains in the output circuit chip are also interconnected through a gold wire 7 or a gold strip two 9.
The input end of the input circuit chip 2-1 is connected with a signal input end pin of the microwave power amplification chip 4 through a gold wire 7; the output end of the input circuit chip 2-2 is connected with the pin of the signal output end 4 of the microwave power amplification chip through a gold wire 7.
It should be noted that the input circuit chip 2-1 is mainly used for rf input and gate voltage power supply, the output circuit chip 2-2 is mainly used for rf output and drain power supply, and the input circuit chip 2-1 and the output circuit chip 2-2 are bridges for interconnecting the microwave power amplification chip and the module level circuit.
The support plate 3 is made of molybdenum-copper alloy or diamond copper, the support plate 3 needs to be made of materials with close thermal expansion coefficients, high thermal conductivity and high electrical conductivity, the molybdenum-copper alloy adopts high-quality molybdenum powder and oxygen-free copper powder, and is formed by isostatic pressing, fine in structure, good in arc breaking performance, good in electrical conductivity and small in thermal expansion; the diamond copper material, namely the diamond particle reinforced copper-based composite material has the thermal conductivity far higher than that of the traditional WCu, MoCu and SiC/Al materials, the thermal expansion coefficient can be adjusted to be matched with a semiconductor chip or a ceramic substrate by controlling the volume content of diamond, and the bending strength is higher than that of oxygen-free copper; the molybdenum-copper alloy or diamond-copper is selected as the carrier plate to meet the actual requirement.
The microwave power amplifying chip 4 is a GaN or GaAs chip, and the output microwave power of the GaN or GaAs chip is large, generally more than 1W, tens, hundreds or even higher.
The input bonding pad, the output bonding pad and the power-up bonding pad of the microwave power amplification chip are all gold wire pressure point bonding pads, and the sizes of the gold wire pressure point bonding pads are generally 0.15mm by 0.15 mm.
The number of the power supply filter circuit chips is two, the power supply filter circuit chips are respectively connected with the drain electrodes of the output circuit chips 2-2 by gold bands, namely the power supply filter circuit chips 1-1 and the power supply filter circuit chips 1-2 are connected with the drain electrodes of the output circuit chips 2-2 by gold bands 9; the power supply filter circuit chip is mainly used for drain power supply filtering.
It should be noted that, for the microwave power amplification chip, the capacitor at the drain end generally needs to use a capacitor meeting the requirement of the supply voltage, so the capacitors in the power filter circuit chip 1-1 and the power filter circuit chip 1-2 are designed according to the uF level or the kilopf level.
One of the coplanar waveguides 17 is connected in parallel between the gate of the input circuit chip 2-1 and the input signal terminal; one of the coplanar waveguides 17 is connected in parallel between the drain of the output chip 2-2 and the output signal terminal; the coplanar waveguide part is added on the input circuit chip 2-1 and the output circuit chip 2-2, so that on-chip test can be carried out on a probe station.
The principle of the carrier plate type microwave power amplifier capable of being tested on a chip is as follows: a radio frequency signal (RFin) is connected to a radio frequency signal input end 12 of the input circuit chip 2-1, and a grid power supply signal is connected to a grid power supply end I11 and a grid power supply end 13 of the input circuit chip 2-1; then, the grid voltage is input to a microwave power amplification chip 4 through a chip capacitor I5-1 and a chip capacitor II 5-2; the output power signal (RFout) of the microwave power amplifying chip is output from the rf signal output terminal 15 of the output circuit chip 2-2. The input circuit sheet 2-1 is provided with a test point of the microwave power amplification chip, which does not exist in an actual circuit, and the test point is only shown here, the test point mainly uses a multimeter to test the grid impedance of the microwave power amplification chip, and if the grid impedance to the ground is less than 100k omega, the test point is unqualified.
The invention is not limited to the foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification and any novel one, or any novel combination, of the steps of any method or process so disclosed. Those skilled in the art to which the invention pertains will appreciate that insubstantial changes or modifications can be made without departing from the spirit of the invention as defined by the appended claims.