CN215179294U - Flexible chip bending capability testing device and flexible carrier - Google Patents

Abstract

The utility model provides a flexible chip bending capability testing device and a flexible carrier, wherein the device comprises a simulation unit, a laminating unit and a testing clamp; at least one part of the simulation unit is a curved surface for bending and attaching with the flexible carrier; the laminating unit is arranged on one side of the curved surface, and a gap for the flexible carrier to pass through is formed between the laminating unit and the curved surface; the test fixture fixes one end of the flexible carrier on one side of the gap; the attaching unit guides the flexible carrier to attach to the curved surface relative to the curved surface. The flexible carrier comprises a flexible substrate layer provided with a test circuit therein; the chip to be tested is fixed on the flexible substrate layer and connected with the test circuit; the flexible medium layer covers the chip to be tested and part of the surface of the flexible substrate layer; an interface for connecting the test circuit is arranged on the flexible medium layer or the flexible substrate layer. The utility model provides an among the prior art to the not enough problem of flexible chip bending property test ability.

Description

Flexible chip bending capability testing device and flexible carrier

Technical Field

The utility model relates to a flexible electron technical field especially relates to flexible chip bending capability testing arrangement and flexible carrier that is used for the test.

Background

In recent years, flexible electronics have become a pursuit of the electronics industry and academia due to their outstanding malleability, adaptability and portability. The biggest characteristic of flexible electronics, which is different from traditional microelectronics, is its "flexibility", which is one of the most important concerns of users, on one hand, the flexible electronics must have the ability to withstand large deformation, and on the other hand, the flexible electronics must also maintain the stability of the original electrical properties after repeated deformation. With the trend of gradually realizing marketization development of flexible electronics, the mechanical reliability of the service of the flexible electronics also gets great attention.

At present, much research on fatigue damage and fracture of flexible electronic devices has been carried out, mainly focusing on passive devices such as flexible display areas, flexible sensors, flexible batteries, and the like. However, with the development of flexible electronic technology, the flexibility research of active devices such as chips and the like is started at home and abroad. In the case of a flexible chip, the electrical properties of the chip have changed significantly before the visible crack occurs, so that not only the conventional environmental reliability but also the mechanical reliability of the chip are effectively tested in the design, development, production, manufacturing and service processes.

Bending is the most common deformation mode in flexible electronic application, and at present, there are four methods for testing the bending mechanical properties of flexible electronics, as shown in fig. 1: (a) the extrusion free bending method is simple to operate, but the bending angle or the bending strain is difficult to quantify; (b) the bending with variable angle can be convenient for calculating the bending strain, but the mechanical automation of the bending operation is more complex; (c) the variable curvature bending and the (d) translational sliding bending both adopt a folding bending mode, the implementation is easy, and the bending strain is convenient to calculate.

The four methods have more applications in the aspects of products such as flexible displays, flexible circuit boards, flexible batteries, flexible capacitors and the like, and the bending capability test of the flexible chip still in the research stage has more limitations: 1) the chip size is small, and the bonding pads are basically distributed at the edge part, so the measurement by the method is not suitable; 2) the thickness is extremely thin, and the phenomena of chip cracking and the like are easily caused when the probe method is adopted to test the electrical performance during bending; 3) the conventional three-point bending-resistant or four-point bending-resistant method is adopted, only the strength of the chip to be tested can be obtained, the electrical performance of the chip to be tested in the bending process can not be obtained, the method belongs to destructive tests, and the tested chips are all in a breaking state.

At present, the means for evaluating the bending strength of a chip in the industry is mainly the three-point bending method specified in International society for semiconductor and materials industries Standard G86-0303. Principle of three-point bending-resistant method: two support bodies are laid down and arranged in parallel to each other, and a chip to be measured is placed on a side surface of the support body without being fixed to the support body. A columnar indenter is disposed above the chip between the two support bodies and parallel to the two support bodies. Then, the chip was broken by pressing it from above with the indenter, and the load applied to the chip at this time was measured as strength. However, in the case of a flexible chip having an extremely thin thickness, even if the chip is pressed by a pressure head during measurement, the chip is bent only and cannot be broken, and the ultimate bending capability of the chip cannot be measured.

To improve this situation, publication numbers are: CN108931203A, chinese invention patent, proposes a bending strength testing apparatus and method for an extremely thin chip, 1) holding one end of a chip on a supporting surface of a first holding unit and the other end of the chip on a supporting surface of a second holding unit; 2) moving the first holding unit and the second holding unit relative to each other so that a cross-sectional shape of a measurement region between one end and the other end of the chip is formed into a circular arc shape so that a supporting surface of the first holding unit faces a supporting surface of the second holding unit; 3) relatively moving the first holding unit and the second holding unit in a direction in which they approach each other; 4) the curvature of the measurement area when the chip breakage is detected. The device can measure the bending strength and the ultimate bending curvature of the chip with the thickness of less than 30 mu m, but the device is only suitable for the chip with larger size (such as 10mm multiplied by 10mm and the like), the measurement is difficult for the smaller chip under the influence of a tool fixture, and the method can not synchronously test the electrical property of the chip under the bending condition.

U.S. Pat. No. US8365611B1 discloses a method and apparatus for testing the bending capability of a flip chip, which mainly includes bending a flip chip device, heating the flip chip device, and checking whether the flip chip device fails. The method is mainly used for simulating the small deformation of the flip chip caused by the influence of thermal stress in the long-time use process and analyzing the chip failure mode under the bending deformation condition, so that the method is not suitable for the flexible chip.

Chinese patent publication No. CN111678801A discloses a flexible electronic bending loading device; mainly utilizing a curved surface with fixed curvature to attach a flexible electronic device so as to detect the limit bending capability of the flexible electronic device; each action time is long and is not suitable for a bending fatigue test; and the device to be tested is subjected to larger pressure and tension, and interference influence is brought to bending test.

The method can not simultaneously test the bending limit and the bending fatigue of the chip, and the test capability is insufficient.

SUMMERY OF THE UTILITY MODEL

Aiming at the defects in the prior art, the utility model provides a flexible chip bending capability testing device, which solves the problem of insufficient flexible chip bending capability testing capability in the prior art; still provide a flexible carrier, solved the chip that exists among the prior art small, difficult by the problem of centre gripping test.

According to an embodiment of the utility model, a flexible chip bending capability testing device is provided, which comprises a simulation unit, a laminating unit and a testing clamp;

at least one part of the simulation unit is a curved surface for bending and attaching with the flexible carrier;

the laminating unit is arranged on one side of the curved surface, and a gap for the flexible carrier to pass through is formed between the laminating unit and the curved surface; the test fixture fixes one end of the flexible carrier on one side of the gap; the laminating unit guides the flexible carrier to be laminated with the curved surface relative to the curved surface.

Also provides a flexible carrier for the flexible chip bending capability testing device, which comprises

Flexible substrate layer: a test circuit used for being electrically connected with the test fixture is arranged in the test fixture;

chip to be tested: fixed on the flexible substrate layer and electrically connected with the test circuit;

flexible dielectric layer: covering partial surfaces of the chip to be tested and the flexible substrate layer.

The technical principle of the utility model is that: bending the flexible carrier by using the testing device, and further driving the chip to be tested to bend along with the bending of the flexible carrier, so as to achieve the purpose of bending and testing the chip to be tested; the curved surface is designed according to the curvature of the test requirement in advance, and the flexible carrier is attached to the curved surface by the aid of an attaching unit through external force or self gravity to achieve the purpose of testing the bending strength. The flexible carrier bears the chip to be tested and has elasticity, and the flexible carrier is structurally formed, so that the chip to be tested can be protected in the bending process and can be detected through the test circuit; the flexible carrier can be used for repeated lamination to achieve the purpose of bending fatigue test.

Compared with the prior art, the utility model discloses following beneficial effect has:

the utility model discloses according to the test purpose, the rational selection camber curvature both can obtain static limit bending capability test, also can carry out dynamic bending fatigue test many times. Meanwhile, the clamping is convenient, and the effect of testing the bent edge can be achieved. The utility model discloses to await measuring the chip fixed and electricity link to the flexible substrate on and protect with the flexible medium layer, overcome the small difficult centre gripping of chip that awaits measuring, the problem of chip electric property under the crooked condition of synchronous test.

Drawings

Fig. 1 is a diagram showing a conventional 4-bend test method.

Fig. 2 is a schematic structural diagram of the flexible carrier.

Fig. 3 is a schematic diagram of the flexible carrier and the clamping plate according to the embodiment of the invention.

FIG. 4 is a front view of a testing device according to an embodiment of the present invention.

FIG. 5 is an isometric view of the embodiment of FIG. 4 with the support plate removed.

FIG. 6 is a schematic representation of the relationship between the diameter changes of the conformable sleeve and the central sleeve in one embodiment.

In the above drawings: 1. a center roller; 2. a flexible carrier; 3. a roller; 4. a splint; 5. swinging arms; 6. a support rod; 7. locking the bolt; 8. a connecting plate; 9. a support plate; 10. a stopper; 11. a rotating shaft; 12. a central sleeve; 21. a flexible substrate layer; 22. a chip to be tested; 23. a first flexible dielectric layer; 24. a test circuit; 25. a second flexible dielectric layer; 31. a swing shaft; 32. fitting the sleeve; 41. testing the probe; 51. a first lock hole; 52. an extension rod.

Detailed Description

The technical solution of the present invention will be further explained with reference to the accompanying drawings and embodiments.

As shown in fig. 2-3, an embodiment of the present invention provides a flexible carrier, which includes:

a flexible substrate layer 21 having a test circuit 24 disposed therein; a chip 22 to be tested fixed on the flexible substrate layer 21 and connected with the test circuit 24; the flexible medium layer covers partial surfaces of the chip 22 to be tested and the flexible substrate layer 21; the flexible dielectric layer or the flexible substrate layer 21 is provided with an interface for connecting the test circuit 24.

The flexible substrate layer 21 is a polyimide layer on which the test circuit 24 and the chip 22 to be tested are arranged in advance, the flexible medium layers include a first flexible medium layer 23 and a second flexible medium layer 25, the first flexible medium layer 23 is made of photosensitive materials and at least covers the surface of the chip 22 to be tested, and the chip 22 to be tested and the test circuit 24 can be conveniently connected by using a rewiring process. In actual setting, the first flexible medium layer 23 is coated on the whole surface of the flexible substrate layer 21 with the chip 22 to be tested, and the thickness of the first flexible medium layer is slightly thicker than the thickness of the chip 22 to be tested after connection, so that the chip 22 to be tested is covered.

The chip 22 to be tested can also be attached to the flexible substrate layer 21 by other common connection methods, and then the second flexible medium layer 25 is directly coated. The first flexible dielectric layer 23 is made of polyimide, but other materials suitable for line connection and suitable for light sensing can be used. The second flexible dielectric layer 25 is made of epoxy resin materials, and plays a role in protecting the chip 22 to be tested, so that the chip is mainly influenced by bending in the bending test process and is not influenced by other concentrated stress.

The flexible substrate layer 21 and the flexible medium layer both have certain elasticity, and can recover by itself or with the help of external force after being deformed, and after the chip 22 to be tested and the two are fixed, the chip can recover with the help of the recovery capability of the two, thereby providing a precondition for repeated bending fatigue test. The flexible substrate layer 21 and the flexible medium layer provide a relatively uniform stress environment for the chip 22 to be tested, so that the chip 22 to be tested cannot be damaged due to relatively large local stress such as clamping and the like, and the influence caused by relatively real reaction bending cannot be caused. The bending limit test is convenient to carry out. The flexible substrate has the conditions for arranging the test circuit 24, can realize the connection with the chip, can be bent and tested, and can reflect the result timely and accurately; and interval experiments are not required to be set during fatigue testing.

One specific manufacturing method of the flexible carrier is as follows: (1) temporarily bonding a flexible substrate on a carrier: a flexible substrate designed with test circuitry 24 is provided having a length and width of 8.0cm 2.0cm and a thickness of 100 μm. Spin-coating a laser response layer material (model: WLP LB210) on a glass plate by using a spin coater, spin-coating a bonding layer material WLP LB4130 matched with the glass plate on the back of the flexible polyimide substrate, and bonding the two together by using a vacuum hot-pressing method. The carrier plate itself should be flat and not easy to deform; the temporary bonding may also be achieved using materials suitable for peeling by heating, UV debonding, etc., as long as the peeling process does not affect the physical properties of the flexible substrate itself. The flexible substrate is temporarily fixed on the carrier plate, so that the flexible substrate can be conveniently moved and positioned, and is not easy to deform under stress, and automatic operation such as chip 22 mounting to be tested is conveniently carried out.

(2) Mounting the chip 22 to be tested on the flexible substrate with the test circuit 24; respectively sticking a flexible storage chip (NorFlash) with a DAF film (model: Hitachi FH-9021) and the like to corresponding positions of a flexible polyimide substrate by using a full-automatic chip mounter (model: DATACON 2200EVO), wherein the thickness of the chip is 25 mu m, and the thickness of the DAF layer is 10 mu m. After being mounted and attached, the flexible chip is placed into a vacuum box for curing, so that the flexible chip is ensured not to displace and the like in the subsequent treatment process.

(3) Connecting the chip 22 to be tested with the test circuit 24; the utility model discloses mainly adopted fan-out connected mode, specifically as follows:

then, the chip fan-out type interconnection wires are manufactured according to the following process: a) coating a layer of photosensitive first flexible medium layer 23 on the surface of the chip 22 to be detected; coating a layer of photosensitive polyimide (model: BL301) with the thickness of 40 μm on the surface of the chip by a spin coater (model: KW-4A); b) a contact type lithography machine (model: URE-2000S/25A), and then on a developing machine (model: Apogee-Developer) to expose the chip pads and the pads on the substrate surrounding the chip, and then curing them; c) in a magnetron sputtering machine (model: Sputter-100Q) with a plating seed layer of Cr

/Au

d) Uniformly coating photoresist (type AZ) on the surface of the sputtered seed layer9260) The thickness is 15 mu m; f) exposing the circuit to be electroplated and the position of the bonding pad by photoetching development; g) in an electroplating machine (model: TP400D) is electroplated with a layer of conductive metal Cu with the thickness of 15 μm; h) removing the redundant photoresist by adopting acetone; i) metal corrosive liquid (model: au corrosive liquid; cr etchant) to remove the sputtered electroplated seed layer.

(4) And coating a second flexible medium layer 25 on the surface of the flexible substrate and reserving an interface for connecting the test circuit 24. Selecting a two-component epoxy resin adhesive (model: KER-6020-F1), uniformly coating the adhesive on the surface of a flexible substrate on a dispensing machine (model: PVA Delta6), wherein the thickness of the adhesive is 50 mu m, and an I/O interface for testing is directly reserved at the same time. The interface may also be disposed on the other side of the flexible substrate.

(5) And (3) stripping the flexible system from the carrier plate when the packaged flexible substrate is placed on a laser de-bonding machine (model: EVG 850DB) and a laser de-bonding mode is adopted. And for other temporary bonding connection modes, corresponding modes such as heating, UV (ultraviolet) glue dissolving and the like are adopted for processing.

A plurality of chips 22 to be tested are attached to the flexible substrate layer 21, and each chip 22 to be tested is individually connected with one test circuit 24. Multiple simultaneous tests may increase testing efficiency.

The thicknesses of the layers of the flexible carrier 2 are mainly determined according to the thickness of the chip 22 to be tested, and the thicknesses expressed in the above embodiments are only used as references for the size relationship between the thicknesses of the layers, and are not limited specifically.

As shown in fig. 3-5, the present invention further provides a flexible chip bending capability testing apparatus, which comprises a simulation unit, a fitting unit and a testing fixture; at least one part of the simulation unit is a curved surface for bending and attaching with the flexible carrier 2;

the attaching unit is arranged on one side of the curved surface, and a gap for the flexible carrier 2 to pass through is formed between the attaching unit and the curved surface; the test fixture 2 fixes one end of the flexible carrier 2 at one side of the gap; the attaching unit guides the flexible carrier 2 to attach to the curved surface relative to the curved surface movement.

The clearance between simulation unit and the laminating unit slightly is greater than the thickness of flexible carrier 2, and after flexible carrier 2 stretched into between simulation unit and the laminating unit, when the laminating unit removed, the guide flexible carrier 2 laminated to the curved surface, accomplished the bending to flexible carrier 2, and then realized the bending to chip 22 that awaits measuring.

In one embodiment, the simulation unit is a center roller 1, the attaching unit is a roller 3, and the roller 3 is parallel to the center roller 1 and is rotatably disposed around the axis of the center roller 1.

The cylindrical surface of the central roller 1 forms a curved surface, the flexible carrier 2 passes through the space between the roller 3 and the central roller 1, and is gradually guided and attached to the curved surface in the process that the roller 3 rotates around the central roller 1; the roller 3 can elastically return when rotating. Therefore, the bending limit test can be carried out by using the central roller 1 with a smaller diameter, and the bending fatigue test can be carried out by selecting the central roller 1 with a slightly larger diameter and controlling the reciprocating rotation of the roller 3. The roller 3 can be made of hard materials such as ABS, plastics, acrylic, metal and the like, the required surface is smooth, the smaller the friction force is, the better the friction force is, the sliding of the flexible substrate on the surface is not influenced, and the damage to the flexible carrier 2 in the guiding process is avoided.

In order to increase the recovery speed of the flexible carrier 2, the bending fatigue testing efficiency is increased. A supporting rod 6 which is parallel to the roller 3 and moves synchronously with the roller 3 is also arranged on one side of the roller 3, and a gap for the flexible carrier 2 to pass through is arranged between the supporting rod 6 and the roller 3. When the roller 3 rotates to return, the flexible carrier 2 is also supported by the supporting rod 6 to return quickly.

During actual installation, the central roller 1 itself may be fixedly arranged or may rotate, and the rotation of the roller 3 around the central roller 1 may be achieved through the following structure: the testing device also comprises a swing arm 5; one end of the swing arm 5 is fixedly connected to a rotating shaft coaxial with the center roller 1, and the roller 3 is fixed to the other end of the swing arm 5. The rotation of the swing arm 5 around the center roller 1 can be realized by a motor or a link structure driving the swing arm 5 to rotate. This embodiment adopts swing arm 5's structure, and the primary function drives gyro wheel 3 and carries out synchronous revolution along with the axis of rotation 11 of center roll 1, reaches the effect of guide laminating, simple structure and realize automatic control easily.

In addition, the shape of the simulation unit can be changed to be a curved surface with other shapes with required curvature, and the fitting is realized by matching the mechanical arm or the common curve fitting motion with the fitting unit. The moving guide attaching can also be completed by utilizing the gravity of the attaching unit to match with a certain path limiting structure.

For different products and different test purposes, the required curved surface curvature requirements are different, so that the diameter requirements of the central roller 1 are also different, and the diameter of the central roller 1 needs to be adjusted; besides the central roller 1 itself can be disassembled for replacement or directly adjusted, the position of the roller 3 needs to be adjusted to ensure that the gap between the two is within a reasonable range. The gap between the central roller 1 and the idler wheel 3 is slightly larger than the thickness of the flexible carrier 2, and the central roller and the idler wheel cannot directly extrude the flexible carrier 2, so that the flexible carrier 2 and the chip 22 to be tested are prevented from being extruded and damaged, and the testing effect is prevented from being influenced; nor can the gap be too large to guide the flexible carrier 2 into good abutment with the central roll 1. In this regard, the present invention provides several embodiments that can address this problem.

In one embodiment, as shown in fig. 6, the center roller 1 includes a rotating shaft 11 and a center sleeve 12 detachably attached to the rotating shaft 11; the end part of the roller 3 is also connected to the swing arm 5 along the radial direction of the central sleeve 12 in a sliding way; the swing arm 5 is also provided with a locking device for fixing the end part of the roller 3.

The sliding connection is matched with the locking device, so that the fixation of any position can be achieved, and the adjustment flexibility is high. When the device is specifically arranged, the swing arm 5 is provided with a first lock hole 51, the first lock hole 51 is a strip hole, and the first lock hole 51 is arranged along the radial direction of the central roller 1; one end of the roller 3 is slidably connected in the first locking hole 51, and the locking device is a locking bolt 7.

Furthermore, the end part of the roller 3 is provided with a connecting plate 8 parallel to the swing arm 5, and the connecting plate 8 is provided with a second locking hole matched with the locking bolt 7. The locking bolt 7 passes through the first locking hole 51 and the second locking hole to be locked, and the arrangement position of the roller 3 and the position of the fixed structure can be separated through the connecting plate 8, so that the installation space is reserved for convenient installation.

Furthermore, the second lock hole is also a bar hole. The connecting plate 8 and the swing arm 5 are clamped through a locking bolt 7 penetrating through two strip holes, and the adjusting distance can be greatly increased through the matching of the two strip holes.

In another embodiment, the swing arm 5 is provided with a row of positioning holes along the radial direction of the central roller 1, and the end of the roller 3 is provided with a positioning pin matched with the positioning holes. The matching of the pin holes is relatively stable and convenient, the adjustment is relatively fixed, and the pin holes are suitable for the situation that the variety is relatively fixed.

In another embodiment, as shown in fig. 6, the roller 3 includes a swing shaft 31 and an engaging sleeve 32 disposed on the swing shaft 31, and the central roller 1 further includes a central sleeve 12 disposed on the rotating shaft 11. Both the conformable sleeve 32 and the central sleeve 12 are configured to be replaceable, fit together, increase in diameter, and decrease in diameter, while maintaining the gap constant or within a reasonable range. The surface requirements of the central sleeve 12 should be in accordance with the surface requirements for the roller 3 described above.

Under the condition that the strength is enough, the rotation of the roller 3 around the central roller 1 can be realized by one swing arm 5, and in the actual setting, in order to enable the rotation to be more stable, the swing arms 5 are provided with two opposite ends of the roller 3.

The test fixture is composed of two parallel clamping plates 4, and the part of each clamping plate 4 for clamping the flexible carrier 2 is perpendicular to the moving direction of the laminating unit. The vertical arrangement of the clamping plate 4 enables the flexible carrier 2 to be not prone to deviation correspondingly in the width direction during testing. When the structure of the central roller 1 is adopted, the clamping plate 4 is parallel to the central roller 1. The electrical measuring means is a test probe 41 provided on one of the clamping plates 4. The front surfaces of the test probe 41 and the flexible carrier 2 are matched by adopting a golden finger structure, and the clamping is relatively stable. In actual setting, one of the two clamping plates 4 is used for fixing the clamping plate, the fixing clamping plate mainly plays a role in supporting the back of the flexible carrier 2 when the flexible carrier is clamped, and the surface of the fixing clamping plate is covered with an insulating layer and can also play a role in buffering as silica gel, rubber, TPU, TPE and the like because the fixing clamping plate needs to be in contact with the back of the flexible substrate; the other is a movable clamping plate, and one surface of the movable clamping plate, which is in contact with the front surface of the flexible carrier, is covered with an insulating layer in the same way, and a clamping groove interface is reserved and can be matched with the test probe 41. When the electrical performance test of the chip is required, the test probes 41 can be arranged on the bracket side by side according to the arrangement mode of the golden fingers, and the test probes 41 are connected with the test machine table through cables. In addition, the position of the movable clamping plate 4 can be adjusted by screw feeding to fit flexible substrates of different thicknesses and test probes 41 of different lengths.

When the device is installed, two ends of the central roller 1 are respectively provided with a supporting plate 9; the swing arm 5 is fixed on the rotating shaft 11, and a stop block 10 for limiting the swing angle of the swing arm 5 is further arranged on the supporting plate 9. A motor or a link mechanism can be arranged on one side of the supporting plate 9 to drive the rotating shaft 11 to rotate, and further drive the swing arm 5 to swing. When the motor is driven, the stepping motor is preferably selected to drive so as to ensure the stability of back-and-forth rotation and enough rotation torque at low speed. An extension rod 52 is further arranged on the swing arm 5 along the rotation direction of the swing arm, and when the swing arm 5 is at the initial position of the rotation path of the swing arm, the extension rod 52 is in contact with the stop block 10; the stopper 10 functions as an initial positioning. Two stoppers 10 are arranged on each supporting plate 9, two extending rods 52 are arranged on each swing arm 5, and the two stoppers 10 are respectively arranged at two ends of the swing path of the two extending rods 52. On the other hand, the stopper 10 also plays a role in safety, prevents the flexible carrier 2 from being damaged or other parts from being damaged due to the fact that the swing arm 5 is too large in rotation angle caused by human setting errors, and improves the running reliability of the equipment. The maximum swing angle of the roller 3 is 180 degrees, at two ends of a swing path, two extension rods 52 can be respectively contacted with respective stop blocks 10, when the maximum swing angle exceeds the maximum swing angle, the rotation of the stepping motor is blocked, the driving current is increased, an alarm mechanism on a power management system can be started, and therefore the stepping motor is powered off, and the testing device and the flexible carrier 2 are protected.

The device uses the roller 3 as a guide piece, the curved surface can be various, and the curvature of the attaching position of the chip 22 to be detected is accurate. The flexible carrier 2 and the curved surface are attached in the following mode: the flexible carrier 2 is driven by a guide piece which reciprocates along the curved surface to do bending deformation and recovery actions, and the flexible carrier 2 passes through a gap formed between the curved surface and the guide piece; and the portion of the flexible carrier 2 that is fixed is parallel to the gap. Therefore, in the process of restoring the guide piece, the curved surface can be restored elastically or by traction, and the effect of bending fatigue test is achieved. In the embodiment, the curved surface is an arc surface, so that the curvatures at all the positions of the attachment are consistent, and the chip 22 to be tested and the flexible carrier 2 are conveniently arranged. In order to reduce the friction between the guide piece and the flexible carrier 2 in the attaching process, the guide piece also selects an arc surface or a cylindrical surface, and the guide piece adopted by the invention is the roller 3.

When the flexible carrier 2 is attached, one end of the flexible carrier is fixed and is directly clamped by a clamp plate 4 generally, so that the stability of an attaching position is ensured; and facilitates direct detection by the subsequent mating test circuit 24.

During testing, one side of the flexible carrier 2 with the flexible medium is attached to the curved surface. The flexible medium is thinner than the flexible substrate, so that the relative position of the chip 22 to be measured and the curved surface is closer, and the actual curvature is closer.

The implementation is as follows, select the appropriate central bush 12 of diameter to install on the axis of rotation 11 that links to each other with the step motor, adjust the position of spacing gyro wheel 3, make its gap between central bush 12 slightly greater than the thickness of flexible carrier 2, make flexible carrier 2 can freely be crooked around central roller 1.

The rotating speed of the stepping motor is set to be 5mm/s, the rotating amplitude is in the range of 60-150 degrees, and the maximum rotating frequency is 10000 times. When the motor is arranged, parameters such as rotating speed, direction and angle are required to be adjustable according to test requirements, and the stepping motor is selected to drive the rotating shaft 11. The angular displacement of the stepping motor is strictly proportional to the number of pulses input and is synchronized in time with the pulses. Therefore, the required rotation angle, speed and direction can be obtained by only controlling the number and frequency of the pulses and the phase sequence of the motor winding through the PLC.

According to the testing conditions of the NorFlash memory chip selected in the step (2) in one of the specific manufacturing methods of the flexible carrier 2, the testing fixture is electrified and pressurized, the electrical data of the chip are collected once every 10 times of bending, and the comparative analysis is carried out until 10000 times of bending is completed, so that the bending capability result of the chip under the curvature radius of 5mm is obtained.

If the ultimate bending capability of the chip needs to be explored, only the central sleeve 12 of the corresponding radius needs to be replaced, and the electrical performance data of the chip bent at the curvature radius is tested.

Finally, although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the present invention can be modified or replaced by other means without departing from the spirit and scope of the present invention, which should be construed as limited only by the appended claims.

Claims (12)

1. The utility model provides a flexible chip bending capability testing arrangement which characterized in that: the device comprises a simulation unit, a fitting unit and a test fixture;

at least one part of the simulation unit is a curved surface for bending and attaching with the flexible carrier;

the laminating unit is arranged on one side of the curved surface, and a gap for the flexible carrier to pass through is formed between the laminating unit and the curved surface; the test fixture fixes one end of the flexible carrier on one side of the gap, and the laminating unit guides the flexible carrier to be laminated with the curved surface relative to the curved surface.

2. The device for testing the bending capability of the flexible chip as claimed in claim 1, wherein the simulation unit is a central roller, and the bonding unit is a roller, and the roller is arranged parallel to the central roller and can rotate around the axis of the central roller in a reciprocating manner.

3. The apparatus as claimed in claim 2, wherein a supporting rod is disposed on one side of the roller and parallel to the roller for synchronous movement therewith, and a space is disposed between the supporting rod and the roller for the flexible carrier to pass through.

4. The device for testing the bending capability of the flexible chip according to claim 3, wherein: the device also comprises a swing arm, wherein one end of the swing arm is fixedly connected to a rotating shaft which is coaxial with the central roller, and the roller is fixed to the other end of the swing arm; and/or the presence of a catalyst in the reaction mixture,

the central roller comprises a rotating shaft and a central sleeve detachably connected to the rotating shaft; and/or the presence of a catalyst in the reaction mixture,

the roller comprises a swinging shaft and a fitting sleeve sleeved on the swinging shaft.

5. The device for testing the bending capability of the flexible chip as claimed in claim 4, wherein the end of the roller is connected to the swing arm in a manner of being adjustable along the radial direction of the central roller; and the swing arm is also provided with a locking device for fixing the end part of the roller.

6. The device for testing the bending capability of the flexible chip as claimed in claim 5, wherein the swing arm is provided with a first locking hole, the first locking hole is a bar hole, and the first locking hole is arranged along the radial direction of the central roller; one end of the roller is connected in the first locking hole in a sliding mode, and the locking device is a locking bolt.

7. The device for testing the bending capability of the flexible chip as claimed in claim 6, wherein the end of the roller is provided with a connecting plate parallel to the swing arm, and the connecting plate is provided with a second locking hole matched with the locking bolt.

8. The device for testing the bending capability of the flexible chip as claimed in claim 4, wherein the swing arm is provided with a row of positioning holes along the radial direction of the central roller, and the end of the roller is provided with a positioning pin engaged with the positioning holes.

9. The apparatus for testing bending capability of a flexible chip as claimed in any one of claims 1 to 8, wherein the test fixture is provided with an electrical testing device for testing electrical properties of a chip to be tested in the flexible carrier.

10. The device for testing the bending capability of the flexible chip according to any one of claims 4 to 8, wherein the central roller is provided with support plates at both ends; the swing arm is fixed on a rotating shaft which is rotatably connected with the supporting plate, and a stop block for limiting the swing angle of the swing arm is further arranged on the supporting plate.

11. The apparatus for testing bending capability of a flexible chip as claimed in claim 10, wherein the swing arm further has an extension rod along its rotation direction, and the stoppers are located at two ends of the swing path of the extension rod.

12. A flexible carrier for use in the device for testing bending ability of any one of claims 1-11, comprising

Flexible substrate layer: a test circuit used for being electrically connected with the test fixture is arranged in the test fixture;

chip to be tested: fixed on the flexible substrate layer and electrically connected with the test circuit;

flexible dielectric layer: covering partial surfaces of the chip to be tested and the flexible substrate layer.

Images