Radio frequency chip test carrier

Abstract

The invention relates to the technical field of radio frequency chip clamps, in particular to a radio frequency chip test carrier which comprises a metal shell and a metal cover plate, the metal cover plate is fixed to the metal shell through screws, a PCB groove used for installing a flexible PCB and a chip groove used for installing a radio frequency chip are formed in the metal shell, and the metal cover plate is fixed to the metal shell through screws. Wherein the chip slot is arranged at the central position of the metal shell, a plurality of PCB slots are arranged at the position close to the side surface of the metal shell, an insulator pin penetrating through the shell is arranged at the position of the side surface, provided with the PCB slots, in the metal shell, and an SMA connector sleeved on the insulator pin is arranged on the outer side surface corresponding to the insulator pin; according to the invention, the flexibility of electrical performance testing is improved, and unnecessary product loss is reduced;

Description

Technical Field

[0001] The present invention relates to the technical field of radio frequency chip fixtures, and in particular to a radio frequency chip test carrier. Background Art

[0002] A radio frequency chip is a chip that can convert radio frequency signals and digital signals. Its main function is to receive, modulate and send radio frequency signals, enabling wireless communication equipment to achieve wireless transmission and reception. Its operating frequency range is between 300kHz and 300GHz. The chip is usually made of brittle materials such as lithium tantalate and lithium phosphate. It has the characteristics of high operating frequency and easy breakage.

[0003] In the electrical performance test of RF chips, the use of test vehicles can greatly simplify the test process and improve test efficiency and accuracy. The current main RF chips will use aging tests, functional tests, and special tests in extreme environments, so more functional requirements such as sealing, heat dissipation, corrosion resistance, and chip protection are proposed for RF test vehicles. At the same time, as the operating frequency range and miniaturization requirements of RF chips become higher and higher, the accuracy requirements and damage resistance requirements for RF chip test vehicles are also getting higher and higher, so requirements such as earthquake resistance, drop resistance, and thermal mismatch buffering are proposed for RF test vehicles.

[0004] Traditional RF test carriers are mostly pressure test fixtures and welding test carriers. Among them, the pressure test fixture is very easy to cause pressure damage to the bare chip due to the excessive pressure caused by the downward pressure operation. Therefore, it is mostly used for electrical performance testing of RF devices, but not suitable for electrical performance testing of bare chips. At the same time, the probes used in pressure test carriers have poor flexibility, and the test accuracy decreases under long-term wear, so regular inspection, calibration and maintenance are required. The welding test carrier achieves the connection and fixation of the chip by coating solder paste and heating and welding. There is a problem that the solder pad is difficult to clean, which affects the subsequent packaging and reuse of the chip and increases product loss. Traditional RF test carriers often find it difficult to take into account the requirements of test accuracy, flexibility, chip protection and sealing. Summary of the invention

[0005] In order to solve the cleaning and damage problems during RF chip testing and improve the accuracy, flexibility and convenience of RF chip testing, the present invention proposes a RF chip testing carrier, including a metal shell and a metal cover plate, the metal cover plate is fixed to the metal shell by screws, and the metal shell is provided with a PCB slot for installing a PCB board and a chip slot for installing a RF chip, wherein the chip slot is arranged at the center of the metal shell, and a plurality of PCB slots are arranged close to the side of the metal shell, an insulator pin penetrating the shell is installed at the side position of the metal shell corresponding to the PCB slot, and an SMA connector sleeved on the insulator pin is installed on the external side corresponding to the insulator pin.

[0006] Compared with traditional test vehicles, the present invention has significant advantages:

[0007] 1. The carrier comes with several PCB boards and two pairs of input / output interfaces. The conduction route of the electrical signal can be flexibly selected through wire bonding. At the same time, the chip fragmentation problem caused by the crimping test carrier is avoided, which improves the flexibility of electrical performance testing and reduces unnecessary product loss.

[0008] 2. The positioning function of PCB slot and chip slot effectively shortens the debugging time of wire bonding operation and reduces the time cost of electrical testing;

[0009] 3. The carrier comes with insulators and SMA connectors to facilitate the connection of test wires; the polarity marks and input and output marks on the outside of the shell and near the chip effectively prevent the wrong direction of chip bonding and wire connection, improving the accuracy and convenience of the test;

[0010] 4. In a further solution, the chip is bonded by coating with conductive glue, which is easy to disassemble and clean, avoiding the subsequent cleaning problem of the welding test carrier, and does not affect the subsequent packaging and reuse of the chip. It also has the effect of buffering thermal mismatch, shock resistance, and drop resistance, effectively reducing chip loss;

[0011] 5. The addition of metal cover and sealing ring improves the sealing of the carrier, which can effectively protect the chip during high-power and time-consuming electrical performance tests such as aging;

[0012] 6. The coating on the shell surface ensures the corrosion resistance and wear resistance of the vehicle shell and extends the service life of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the external structure of a radio frequency chip test carrier of the present invention;

[0014] Figure 2 This is a schematic diagram of the internal structure of a radio frequency chip test carrier of the present invention;

[0015] Among them, 1-1, metal cover plate; 1-2, glass window; 1-3, metal shell; 1-4, fixing ear; 1-5, hexagon countersunk screw; 1-6, input / output mark; 1-7, flat head screw; 1-8, metal washer;

[0016] 2-1, PCB slot; 2-2, PCB board; 2-3, solder pad; 2-4, chip slot; 2-5, SMA connector; 2-6, insulator; 2-7, sealing ring. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] The present invention proposes a radio frequency chip test carrier, comprising a metal shell and a metal cover plate, wherein the metal cover plate is fixed to the metal shell by screws, a PCB slot for installing a PCB board and a chip slot for installing a radio frequency chip are arranged inside the metal shell, wherein the chip slot is arranged at the center position of the metal shell, a plurality of PCB slots are arranged close to the side position of the metal shell, an insulator pin penetrating the shell is installed at the side position where the PCB slot is arranged in the metal shell, and an SMA connector sleeved on the insulator pin is installed on the external side corresponding to the insulator pin.

[0019] The RF chip test carrier in this embodiment is composed of a metal shell, an insulator, a test connector, a PCB board, a PCB slot, a chip slot, a ground pad, a metal cover, an insulator, an SMA connector, screws and a rubber sealing ring, wherein:

[0020] The metal shell is made of 45# steel, and you can also choose 40Cr stainless steel, hard aluminum alloy and other metals with strong thermal conductivity and good heat dissipation effect to ensure that the metal shell can adapt to harsh test environments such as aging tests. The shell is 4mm thick and contains a cavity structure of 32mm×32mm×4mm. The cavity contains chip slots, PCB slots, and soft PCB boards. The side walls of the shell have insulators, SMA connectors and screws, and the bottom of the outer side of the shell has a pair of fixing ears.

[0021] The PCB board and the chip are connected by wire bonding, and there is no need to use a pressure test probe, thereby effectively preventing chip damage caused by pressure, and no need for regular inspection and calibration, and also avoiding test errors caused by probe wear, effectively reducing chip loss and carrier maintenance costs;

[0022] In this embodiment, the PCB board is made of FR-4 epoxy glass cloth laminate. Those skilled in the art can select ceramic substrates, metal substrates, polymer substrates, etc. according to actual needs. The length × width × height of the PCB board is 4mm × 6mm × 1mm, and the length and width can be adjusted within the range of ±0.5mm;

[0023] The PCB slot is 0.5 mm deep, and the edges are slightly wider than the PCB board by 0.5 mm, so as to achieve the positioning effect when the PCB board is installed; the bottom of the PCB slot can be plated with gold or silver to ensure good adhesion between the PCB slot and the conductive glue. As a way to fix the PCB board in the PCB slot, the PCB board can be bonded in the PCB slot by coating conductive silver glue, copper powder conductive glue, silver copper conductive glue and other materials on the bottom of the PCB slot, and then the conductive glue is heated and cured, so that the fixed device not only has good thermal conductivity, but also can buffer the thermal mismatch between the PCB and the metal carrier, and achieve anti-vibration and anti-drop effects; as another way to fix the PCB board in the PCB slot, lead or lead-free solder paste such as SAC305, 63Sn37Pb, Sn43Pb43Bi14 can be coated in the PCB slot, the PCB board can be manually mounted, and then reflow soldering can be performed to achieve the connection between the PCB board and the metal shell. In actual operation, technicians need to pay attention to the following points: before applying conductive glue or solder, the PCB slot should be cleaned and inspected to prevent dirt on the surface, which will affect the bonding and welding effects and thus the electrical test results. In addition, when applying conductive glue and solder paste, it is necessary to ensure that the conductive glue and solder paste completely cover the bottom of the PCB slot;

[0024] Each PCB board has a pair of pads with a size of 0.8mm×0.8mm×0.5mm. The pads can be made of copper-plated gold to install decoupling components to shield interference signals and ensure the stability and accuracy of electrical test signals. Nickel-palladium-gold, nickel-palladium-silver, and copper can also be used to achieve wire bonding between the PCB board and the chip to ensure good conductivity and bonding reliability. The bonding wire can be gold wire, aluminum wire, or copper wire.

[0025] The chip slot has a size of 6mm×6mm×0.5mm and can be used to mount chips with a width of 5 to 5.5mm. It is used for positioning during chip bonding. The bottom of the chip slot is plated with gold or silver to ensure good adhesion between the chip slot and the conductive adhesive. The chip is bonded to the chip slot by coating conductive silver adhesive, copper powder conductive adhesive, silver copper conductive adhesive and other materials, and then heated and cured. The chip fixed by this method is easier to clean than the welding test, and does not affect the subsequent use of the chip. It can also buffer the thermal mismatch, shock resistance and drop resistance between the chip and the metal carrier, effectively reducing chip loss. Laser engraving is used near the chip slot to make "+" and "-" polarity marks to ensure the correct chip bonding direction and the accuracy of electrical testing. The positioning function of the chip slot and the PCB slot is used to limit the relative position between the chip and the PCB board, which can effectively shorten the debugging time of the wire bonding operation and improve convenience and work efficiency.

[0026] There are two ground pads in total, with dimensions of 1mm×1mm×0.5mm, which are slightly larger than conventional pads. The ground pads can be made of materials such as nickel-palladium-gold and nickel-palladium-silver, and are connected to the chip by wire bonding, which can prevent electromagnetic interference and electrostatic interference, improve heat dissipation efficiency, and reduce damage caused by chip overheating; the two ground pads are symmetrically distributed on both sides of the chip slot, located between the chip slot and the PCB slot, so as to shorten the lead length, reduce interference signals, and improve circuit stability.

[0027] The insulator shell and needle are made of pure copper, the insulating medium is glass, the diameter is 4mm, the length of the copper needle extending into the shell is 2mm, and the length of the part extending out of the shell is 6mm. The length of the copper needle can be appropriately adjusted according to the bending and welding requirements; the insulator penetrates the shell wall, and its upper and lower surfaces are flush with the shell surface. The connection with the shell is achieved by coating silver paste, solder paste or sintering, and then the insulator needle and the PCB board are interconnected by manual welding; technicians in this field should pay attention to the following points during the implementation process: the silver paste and solder paste should be applied in an appropriate amount to completely cover the side wall of the insulator, and should not overflow to the end face of the insulating medium after being inserted into the shell, so as to prevent the lead pin from short-circuiting with the carrier shell;

[0028] The shell and inner wall of the SMA connector are made of pure copper, the insulating medium is ceramic, the diameter is 6mm, the length is 10mm, and a pair of flange edges of 5.5mm×3mm×2mm are distributed on both sides of the bottom of the SMA connector for mounting screws. There are 4 SMA connectors coaxially connected to the insulator, as 2 input and 2 output terminals for flexible selection; a laser marking machine is used next to each SMA connector to engrave the "IN" or "OUT" mark to ensure correct external connection during testing. The laser engraving depth is 0.1mm to avoid unclear text caused by long-term wear; each connector is fixed to the side wall of the shell by a pair of M1.6 flat head screws to ensure connection reliability, prevent the connector from falling off and the insulator pin from deforming, and the screws are optional High-strength high-carbon steel, alloy steel, copper-zinc alloy and other materials, thread diameter 1.6mm, length 5.5mm to ensure connection strength, flat head screw and connector are equipped with M1.6 metal washers, materials can be selected 65MN spring steel, 70# carbon steel, 3Cr13, SUS304, etc., the washer thickness is 0.3mm, with anti-vibration effect, can ensure the stability of the connection between the SMA connector and the insulator, thereby improving the stability of the RF test signal; the metal washer material can be selected from high-toughness medium carbon steel, low-carbon alloy steel, etc. The corresponding threaded holes on the side wall of the shell are blind holes to ensure the sealing of the shell, meet the chip protection requirements in special electrical performance tests such as aging and special tests, and can also be designed as through holes to prevent dirt, facilitate cleaning, and adapt to general electrical test conditions;

[0029] The fixing ears are integrated with the shell and are located on both sides of the bottom of the shell. The size is 8mm×6mm×2mm. There is a threaded through hole with a diameter of 2mm in the middle of the fixing ears, which is used to fix the position of the carrier and prevent vibration to ensure the stability of the test signal.

[0030] The material of the metal cover is consistent with that of the shell, and a viewing window of 24mm×24mm is opened in the middle of the cover, which is convenient for checking the appearance changes and connection conditions of the chip and the lead at any time during the time-consuming electrical test process such as aging. The window material can be selected from high-strength transparent materials such as tempered glass and polycarbonate to meet the reliability and life requirements;

[0031] The opening of the optical window in this embodiment, in conjunction with the fixing ears, broadens the application scope of the test fixture, such as observing the chip and lead status at any time during electrical aging, power loading, high-frequency vibration, etc., thereby improving the convenience and applicability of the product test fixture;

[0032] The shell and the cover plate are fixedly connected by M1.6 hexagonal countersunk screws. The screw material can be selected from high carbon steel, alloy steel, etc. The thread diameter is 1.6mm and the length is 5mm. The corresponding threaded hole on the shell is a blind hole or a through hole. There is an annular groove at the joint surface of the shell and the cover plate. The depth of the groove above and below is 1mm. The groove has a built-in sealing ring. The sealing ring material can be selected from rubber, polytetrafluoroethylene, combined sealing ring, etc. to ensure the sealing of the shell and adapt to test conditions with special protection requirements such as aging tests and special tests. At the same time, the surface of the shell, except for the chip slot and PCB slot area, is nickel-plated with a coating thickness of 2 to 10 microns. A thickness of 2 microns can be selected to take into account both conductivity and corrosion resistance, or a thickness of 10 microns can be selected to take into account both wear resistance and corrosion resistance.

[0033] The outer dimensions of the carrier are not limited to a square, but may also be a circle; the number of the test input and output ports is not limited to four, but may be adjusted according to the changes of the test signal.

[0034] In the description of the present invention, it is necessary to understand that the terms "coaxial", "bottom", "one end", "top", "middle", "the other end", "upper", "one side", "top", "inside", "outside", "front", "center", "both ends" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0035] In the present invention, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "rotation" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the present invention according to the specific circumstances.

[0036] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A radio frequency chip test carrier, characterized in that: It includes a metal shell and a metal cover plate, which is fixed to the metal shell by screws. The metal shell is provided with a plurality of PCB slots for installing PCB boards and a chip slot for installing radio frequency chips, wherein the chip slot is arranged at the center of the metal shell, an insulator pin penetrating the shell is installed at the side position of the metal shell corresponding to the PCB slot, and an SMA connector sleeved on the insulator pin is installed on the external side corresponding to the insulator pin.

2. The RF chip test carrier according to claim 1, characterized in that: The bottom of the PCB slot and chip slot is gold-plated or silver-plated, and the thickness of the gold-plated or silver-plated PCB pad is greater than 2.5μm.

3. The RF chip test carrier according to claim 2, characterized in that: The RF chip and PCB board are respectively bonded to the bottom of the chip slot and the PCB slot by coating conductive glue, and the conductive glue is cured by heating to fix the RF chip and the PCB board in the chip slot and the PCB slot respectively.

4. The RF chip test carrier according to claim 2, characterized in that: Solder paste is applied to the chip slot and the PCB slot, and the RF chip and the PCB board are fixed in the chip slot and the PCB slot respectively by reflow soldering.

5. The radio frequency chip test carrier according to claim 2, characterized in that: A ground pad is provided on both sides of the chip slot. The PCB board is connected to the nearest ground pad by wire bonding. The material of the ground pad is nickel-palladium-gold or nickel-palladium-silver and the size of the ground pad is larger than that of other pads.

6. The radio frequency chip test carrier according to claim 1, characterized in that: The PCB board is provided with matching component mounting pads that meet the requirements of RF chip function testing.

7. The RF chip test carrier according to claim 1, characterized in that: The length of the insulator needle extending into the shell is 2 mm, and the length extending outside the shell is 6 mm.

8. The radio frequency chip test carrier according to claim 1, characterized in that: The metal shell, metal cover and insulator pins are made of pure copper.

9. The radio frequency chip test carrier according to claim 7, characterized in that: A glass window is arranged at the center of the metal cover plate, and a sealing ring is arranged between the metal cover plate and the metal shell.

10. The radio frequency chip test carrier according to claim 1, characterized in that: The insulator shell and needle are made of pure copper, and the insulating medium is glass; the insulator penetrates the shell wall, and its shell and insulating medium body should be flush with the inner and outer surfaces of the shell side wall. The connection with the shell is achieved by coating silver paste and sintering solder paste, and the interconnection between the insulator needle and the PCB board is then achieved by manual welding.

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