1851 results about "Test structure" patented technology

The invention relates to the technical field of pipe bracket testing, in particular to a thermal insulation pipe bracket overall strength displacement overload testing device and method.The thermal insulation pipe bracket overall strength displacement overload testing device comprises a bearing base and further comprises a pipe bracket base arranged on the upper side of the bearing base, a connecting pipe bracket is installed at the upper end of the pipe bracket base, a clamping plate is clamped to the upper side of the bearing base, and a rotating shaft is arranged on the clamping plate in a penetrating mode; the bottom end of the rotating shaft is clamped and connected with a connecting gear, and an annular groove is formed in the edge of the upper side of the bearing base. According to the invention, the axial and radial strength of the pipe bracket can be tested in the displacement overload test process, the use limitation is low, the automation degree is high, the test efficiency of the heat insulation pipe bracket is obviously improved, the situation that the pipe bracket is broken to injure people due to broken objects in the displacement overload test process of the pipe bracket can be avoided, and the test efficiency is improved. The displacement overload test structure has a good safety protection function, is high in use safety, and also realizes a step-by-step disassembly function of the displacement overload test structure, so that barrier-free maintenance of the test structure is facilitated.

The invention relates to the technical field of steel reinforced concrete vibration testing, and discloses a method and system for testing the vibration performance of a steel reinforced concrete frame structure, and the state of the steel reinforced concrete frame structure is judged through vibration amplitude and frequency changes under the conditions of different excitation modes, measurement point positions, sampling frequencies, collection durations and the like. By accurately measuring and analyzing the change of the damping ratio, potential damage or performance change of the structure can be found in time, and a powerful basis is provided for safety assessment and maintenance of the structure; the signal is decomposed and analyzed based on Hilbert-Huang transform, the internal composition and the change rule of the structure vibration signal can be analyzed more finely, and the method has advantages for identifying weak vibration characteristics and early damage signs of the structure in a complex stress state, so that the test structure can be evaluated in time in the early damage stage, and the test accuracy is improved. And therefore, coping treatment can be conveniently carried out.

The invention relates to the field of coating performance testing, in particular to a real stone paint coating performance detection device which comprises a box body, a supporting rod, a clamping mechanism, an overturning mechanism, a box cover, a testing mechanism and a flushing mechanism. The clamping mechanism, the testing mechanism, the overturning mechanism and the flushing mechanism are matched with one another, so that the anti-cracking performance test, the stain resistance test and the scratch resistance test can be carried out on the real stone paint coating, the test cost is reduced, and the tests are carried out in a closed space formed by the box body and the box cover; according to the utility model, the left side of the closed space formed in the box body and the box cover is respectively provided with the refrigerating device, the heating device and the temperature sensor, so that the temperature of the closed space is increased; the two parts cooperate with each other to test the freeze-thaw performance of the stone-like coating on the left side of the closed space, another stone-like coating playing a contrast role is clamped on the right side of the closed space, and a freeze-thaw performance test result can be compared and observed.

The invention relates to the technical field of rock mass testing, in particular to a tunnel water-rich fault fracture zone area loading simulation test device and method.The tunnel water-rich fault fracture zone area loading simulation test device comprises a test box, and a partition plate is arranged in the test box; the partition plate divides the test box into a first area and a second area, and the second area is filled with a rock-soil sample; a lateral loading structure; a vertical loading structure; the simulated fault test structure comprises a mounting frame fixedly connected to the partition plate, a driving structure and a simulated fault unit, one end of the driving structure is hinged to the mounting frame, and the other end of the driving structure is connected with the simulated fault unit; the fault simulation unit is hinged to the mounting frame and used for simulating an adjustable fault, and the technical problems that an existing test device cannot dynamically adjust the fault fracture width and the dip angle according to the load effect and cannot perform real-time coupling simulation on a hydrological seepage field are solved.

The invention discloses a method and a system for evaluating the reliability of a side wall gate oxide process and electronic equipment thereof. In the TDDB test structure, the gate length L of a single finger is adjusted by increasing or reducing the number of fingers, and then a reliability test is performed to obtain a TDDB test result; and performing data fitting by using L, a TDDB test result and a gate leakage current logarithm, and finally obtaining the TDDB life of the overlapping area of the LDD region and the gate and the quality of a gate oxide layer between the lower source and drain near the side wall and the gate. The invention provides a new calculation method which is used for making up the technical blank of reliability evaluation of part of gate oxide near a side wall in the prior art. According to the method, the TDDB service life of the overlap area Sov of the LDD region and the gate is evaluated more accurately, so that a process engineer is helped to deeply understand and control the manufacturing process of the gate oxide layer, especially in the side wall and the poly region, and the optimization of the manufacturing process of part of the gate oxide layer near the side wall is facilitated.

The invention discloses a scattering parameter de-embedding method, device and equipment, and relates to the technical field of semiconductors. The method comprises the following steps: obtaining n de-embedding test structural members; constructing a first ABCD matrix and a second ABCD matrix according to the first admittance and the second admittance; according to the third admittance, the fourth admittance and the length of each transmission line in the n transmission lines, constructing n third ABCD matrixes; the third admittance is the admittance between the unit length transmission line and the ground in the equivalent pi-type circuit corresponding to the unit length transmission line, and the fourth admittance is the admittance of the unit length transmission line; and according to the first ABCD matrix, the second ABCD matrix and the n third ABCD matrixes, solving to obtain a de-embedded ABCD matrix of the to-be-tested device, and converting the ABCD matrix of the to-be-tested device into scattering parameters. According to the embodiment of the invention, scattering parameter de-embedding can be more efficiently and flexibly realized, so that the overall scattering parameter de-embedding efficiency and precision can be effectively improved.

The invention belongs to the technical field of performance testing, and particularly discloses an intelligent testing system and method for the impedance performance of an HDI circuit board, and the method comprises the steps: immediately starting an interlayer collection module after the lamination of each line layer, carrying out the electrical precise alignment through a POFV test structure, and collecting the in-situ impedance data; the diagnosis prediction module analyzes and processes the data, generates an impedance deviation parameter set, calculates an impedance performance standard coefficient fused with a layer influence factor, and analyzes and outputs a trend result through a time sequence; the impedance state judgment module carries out abnormity judgment based on a preset rule according to the standard coefficient and the trend result; when the judgment result is abnormal, an adjustment triggering marking module is started; and finally, a test report output module generates a test report containing the impedance performance score and the impedance performance distribution of the whole board. According to the invention, layer-by-layer, real-time and closed-loop intelligent test and regulation of impedance performance are realized, and product quality and production efficiency are effectively improved.

The invention discloses a detection method for representing interface roughness of an interconnection structure by using low-frequency noise. According to the method, constant low current is applied to a to-be-tested structure, output current of the to-be-tested structure is measured, and then random current fluctuation generated by interaction of electrons and interconnection structure interfaces, defects and phonons is obtained; fourier transform is carried out on random current fluctuation to obtain frequency domain parameters of the current; calculating the power spectrum density of random current fluctuation according to the frequency domain parameter of the current; wherein the PSD is proportional to the f, and then fitting is carried out to obtain a slope k; and evaluating the interface roughness of the interconnection structure by using the slope k. According to the method, the experiment can be rapidly completed under the condition that the sample is not damaged, and the reusability of the sample is improved. In addition, the low-frequency noise characterization method does not need direct contact or imaging, is suitable for testing packaged chips, and can measure the overall roughness of long interconnection line segments at the same time.

A model parameter test structure for a transistor includes: a substrate, having a first conductivity type, a plurality of isolation structures being provided in the substrate and the isolation structures being used to isolate different doped regions; a first test device, formed in the substrate and configured to obtain characteristic parameters of a source side of the transistor; and a second test device, formed in the substrate and configured to obtain characteristic parameters of a drain side of the transistor; wherein a structure of the first test device is different from a structure of the second test device.

The invention relates to the technical field of semiconductor testing, in particular to a radio frequency testing bonding pad and a radio frequency testing structure. The radio frequency test pad comprises a substrate; the connection supporting layer is located on the substrate, and the connection supporting layer comprises a metal layer; the connection ports are located on the connection supporting layer, and the connection ports comprise a grounding port and a signal port; the grounding port is conductively connected through the metal layer; the signal port and the metal layer are not conductive. The signal port and the metal layer are arranged to be non-conductive, so that potential difference between the signal port and a structure below is avoided, parasitic capacitance is inhibited, and the accuracy of radio frequency testing is further improved.

A semiconductor test structure includes a first transistor active area comprising at least a first source / drain region, and a second transistor active area stacked on the first transistor active area and comprising at least a second source / drain region. At least one dielectric layer is disposed between the first transistor active area and the second transistor active area. The semiconductor test structure further includes a plurality of contact structures spaced apart from each other and disposed on the second source / drain region, and at least one gate structure extending across the first transistor active area and the second transistor active area. Contact resistance is measured between respective ones of the plurality of contact structures and the second source / drain region, and the second source / drain region is continuous between the plurality of contact structures.

The invention provides a static random access memory mismatch test structure and a test method, the static random access memory mismatch test structure comprises a plurality of rows of ring oscillators with different stages, a decoder and a multiplexer, and the stages of each row of ring oscillators are sequentially increased. The ring oscillator in each row comprises a plurality of first phase inverters connected in series and a plurality of second phase inverters connected in series, the input ends of the plurality of first phase inverters are connected in series with the output ends of the plurality of second phase inverters, each first phase inverter is composed of a first PMOS tube and a first NMOS tube in the storage unit, and each second phase inverter is composed of a second PMOS tube and a second NMOS tube in the storage unit. The first phase inverter is composed of a first PMOS transistor and a first NMOS transistor in the memory cell, the second phase inverter is composed of a second PMOS transistor and a second NMOS transistor in the memory cell, so that the layout area of the static random access memory mismatch test structure is smaller than that of an existing mismatch device test structure, and the area occupied by the static random access memory mismatch test structure is saved.

The invention discloses a fan main shaft bearing testing machine, which belongs to the field of fan bearing testing, solves the problems of complicated testing structure, complicated testing steps and inaccurate testing in the prior art, and adopts the technical scheme that the fan main shaft bearing testing machine comprises a platform, a main shaft arranged on the platform in a split manner, and a driving assembly for driving the main shaft to rotate, the platform is further provided with a testing station which is located in the radial direction of the main shaft and used for testing a bearing bush of a single sliding bearing, the testing station is provided with a first pressure sensor, a second pressure sensor and a loading unit, and the first pressure sensor is used for detecting oil film pressure between the bearing bush of the sliding bearing and the main shaft; the loading unit is used for driving a bearing bush of the sliding bearing in the radial direction of the main shaft so as to provide radial loading force for the bearing bush of the sliding bearing, and the second pressure sensor is used for detecting the radial loading force provided by the loading unit. According to the invention, the test structure and the test steps are simplified while the test accuracy is mainly improved.

The utility model provides a flat plate type transfer ironing machine test structure for simulating white dots of a roller type transfer ironing machine, which comprises a flat plate type transfer ironing machine, the flat plate type transfer ironing machine comprises a bottom plate and a heating plate, transfer printing paper and a printing stock are arranged between the heating plate and the bottom plate, and a breathable carrier is arranged on one surface of the transfer printing paper, which is not contacted with the printing stock. The number of white dots after transfer printing of the flat plate type transfer ironing machine is increased; compared with the prior art, the air permeability of the periphery of the transfer printing paper is changed, so that the transfer printing effect on the flat plate type transfer ironing machine can be close to that of a roller type transfer ironing machine, and white spots which can appear on the roller type transfer ironing machine but cannot appear on the flat plate type transfer ironing machine can be transferred by the flat plate type transfer ironing machine; transfer paper manufacturers can adjust the process in time and improve the transfer paper.

The invention discloses a semiconductor test structure and a test method thereof, and belongs to the field of semiconductors. The test structure comprises at least two metal layers arranged on a substrate, the metal layers at least comprise a lower metal layer and an upper metal layer, the lower metal layer is arranged close to the substrate and at least comprises a test area, a test area, a contrast area and a reference area, the test area is arranged between the test area and the contrast area, and the reference area is arranged between the test area and the contrast area. The reference area is arranged on one side of the test area, the inspection area and the contrast area, and the upper metal layer is arranged on the test area, the contrast area and the reference area; the metal plug is arranged between the upper metal layer and the lower metal layer; the first bonding pad is arranged on the upper metal layer on the reference region; the second bonding pad is arranged on the upper metal layer on the test area; and a third pad disposed on the upper metal layer on the contrast region. According to the semiconductor test structure and the test method thereof provided by the invention, the position of an electric leakage defect in the semiconductor structure can be accurately positioned.

The invention discloses a semiconductor test structure and a manufacturing method thereof, and belongs to the technical field of semiconductors, and the test structure at least comprises a substrate which comprises a plurality of active regions which are arranged in parallel; the grid electrodes are arranged on the active areas in parallel, grid electrode dielectric layers are arranged between the grid electrodes and the active areas, and the grid electrodes are perpendicular to the active areas; the first metal silicide is at least arranged on a part of the grid electrode and the side wall of one side of the grid electrode and extends to the active region; at least one test hole group is formed in a single active region between adjacent grids, and the test hole group and the first metal silicide are distributed in a staggered manner; the connecting hole is formed in the active region on one side of the plurality of grids; the at least one first test point is arranged on the test hole group and is connected with the test hole group; and the second test point is arranged on the connecting hole and is connected with the connecting hole. According to the semiconductor test structure and the manufacturing method thereof provided by the invention, the manufacturing quality of the metal silicide can be fed back in time, and the monitoring efficiency is improved.

The invention discloses electronic detonator spot welding defect detection equipment which comprises a bottom bearing plate, a telescopic fixing structure is arranged at the upper end of the bottom bearing plate, a circulating feeding structure is arranged in the telescopic fixing structure, and a testing structure is arranged at the upper end of the telescopic fixing structure. The telescopic fixing structure comprises side supporting plates symmetrically and fixedly arranged on the top face of the bottom bearing plate. According to the electronic detonator spot welding defect detection equipment provided by the invention, the telescopic fixing structure is arranged, and two groups of transverse electric push rods which are symmetrically arranged drive clamping plates at the upper ends to get close to each other, so that electronic detonator control plates with different sizes on the surface of the top plate can be fixed; and meanwhile, a longitudinal electric push rod is matched to drive a test meter and a test needle head on the top to descend to be in contact with a welding spot on the surface of the control panel, so that whether the welding spot has pseudo soldering or not can be detected, compared with an existing detection device, the detection efficiency of the control panel can be effectively improved, and meanwhile higher adaptability is achieved for control panels of different sizes.

The present invention discloses a plastic film corrosion resistance performance testing device and a testing method, and relates to the technical field of testing devices. The plastic film corrosion resistance performance testing device comprises a U-shaped plate, and an upper telescopic cylinder is fixedly installed on the top inner wall of the U-shaped plate. The present invention places the plastic film to be tested on the top of two lower sealing sleeves, and then starts the upper telescopic cylinder. The output end of the upper telescopic cylinder stretches and drives the L-shaped plate to move downward, thereby causing the two upper sealing sleeves to move downward. The two upper sealing sleeves move downward to press the plastic film against the top of the two lower sealing sleeves. The corrosive liquid can be discharged into one of the upper sealing sleeves through a liquid inlet mechanism, and then the strength of a normal plastic film and a corroded plastic film can be compared by providing two test structures. The strength of the normal plastic film and the corroded plastic film can be marked by two marking mechanisms, and it is convenient for users to observe and compare.

The invention discloses a shaft current test structure and method for a motor EMC (Electro Magnetic Compatibility) on-load test system, which are based on a shaft current test structure with a test unit, test shaft current on a test shaft by using a current probe and obtain shaft current data through an EMI (Electro Magnetic Interference) receiver and a computer; the method is simple, convenient and rapid to operate and high in test efficiency, an existing motor EMC on-load test system does not need to be greatly changed, a current probe is adopted to test the shaft current, non-invasive measurement is adopted, and interference to normal operation of the system is reduced to the maximum extent; according to the invention, the problems that the current shaft current test method only focuses on the shaft current test of the motor itself, the comprehensiveness and reliability are poor, and the shaft current test requirement of the motor EMC on-load test system is difficult to meet can be effectively solved; the influence of the shaft current on the motor EMC on-load test can be explored, and the correlation degree and the action mechanism between the shaft current and the electromagnetic compatibility can be deeply analyzed and evaluated.

The invention discloses a wafer electrical property test method, a storage medium and a terminal. The wafer electrical property test method comprises the following steps: acquiring a standard acupuncture image; obtaining a to-be-detected acupuncture image of the current test structure; judging whether the to-be-detected acupuncture image accords with expectation or not based on the standard acupuncture image; if so, completing the electrical test of the current test structure, and carrying out the electrical test of the next test structure; if not, increasing the insertion depth of the probe card of the current test structure once or multiple times; and after the needle insertion depth of the probe card is increased each time, re-acquiring a to-be-detected needle insertion image of the current test structure, and judging whether the re-acquired to-be-detected needle insertion image conforms to expectation or not. In the process of performing the electrical test on the current test structure, whether the needle insertion of the current test structure meets the expectation or not can be detected, so that the time of re-testing due to abnormal test data caused by the needle insertion problem after the test is completed is saved, and the efficiency of the electrical test of the wafer is effectively improved.

The invention discloses a mechanical and ground stress combined loading device based on an underground structural member and a loading method thereof, and relates to the technical field of explosion tests. The dynamic response problem of an existing underground structure under the coupling action of soil stress and explosive load is solved. The device comprises an explosive load applying system and a surrounding stress applying system. The explosion load applying system comprises a lifting mechanism, a guide rail, a drop hammer and a test model; the confining stress applying system applies horizontal confining pressure and vertical confining pressure to the test model; the lifting mechanism drives the drop hammer to realize lifting at different heights; the drop hammer applies a vertical uniformly-distributed explosion-like load to the test model; an enclosure structure is arranged at the top of the test model, and sandy soil is arranged in the enclosure structure; a cover plate is arranged at the top of the enclosure structure, a cushion layer is arranged on the cover plate, and a buffer is arranged on the cushion layer; strain gauges are arranged on the surface of the bottom of the test model; and pressure sensors are arranged in the sand dispersion layer and on the inner surface of the test structure model. The method is suitable for underground structure anti-explosion overall effect model test research.

The invention provides a semiconductor test structure and a test method thereof. The semiconductor test structure is arranged on a scribing channel of a wafer, and comprises a transistor which comprises a substrate, a source electrode, a drain electrode and a grid electrode; the electric fuse comprises a first end and a second end; wherein the source electrode is electrically connected to the first bonding pad through a first metal wire, the second end of the electric fuse is electrically connected to the second bonding pad through a second metal wire, the drain electrode, the substrate and the first end of the electric fuse are electrically connected to the third bonding pad through corresponding third metal wires, and the grid electrode is electrically connected to the fourth bonding pad through a fourth metal wire. Voltage is applied to the first bonding pad, the second bonding pad, the third bonding pad and the fourth bonding pad by adopting a preset rule so as to test the resistance of the electric fuse and the performance of the transistor. According to the technical scheme, the resistance of the electric fuse and the performance of the transistor can be simultaneously monitored in the line in the wafer manufacturing process, the process is rapidly adjusted, and the flexibility of the process is improved.

The embodiment of the invention provides a semiconductor test structure and a manufacturing method thereof, and the semiconductor test structure comprises a test array region which comprises test active regions arranged in an array. The plurality of test conductive wire groups are arranged along the first direction, each test conductive wire group comprises two test conductive wires which are adjacently arranged and a connecting part which is connected with the first ends of the two test conductive wires, each test conductive wire extends and penetrates through the test array area along a second direction, and the second direction is perpendicular to the first direction. And the at least one electric connection structure and the two external connection structures are located on the second ends of the test conductive wires in the plurality of test conductive wire groups, and the first ends and the second ends of the test conductive wires are opposite to each other. The at least one electric connection structure is electrically connected with the adjacent test conductive wires in the adjacent test conductive wire groups in the plurality of test conductive wire groups, and the two external connection structures are electrically connected with the two outermost test conductive wires in all the test conductive wires in the plurality of test conductive wire groups respectively.

The invention discloses a combined load synchronous application testing device. The technical problems that in the prior art, the load applying mode is single, and the combined load cannot be synchronously applied are solved. The device comprises a connecting mechanism and a load applying mechanism, wherein the load applying mechanism comprises a torsional load applying structure, a load transmitting structure and a multi-linkage testing structure. The load transmission structure comprises a special-shaped stress plate and a torsional load transmission assembly, and the torsional load transmission assembly comprises a connecting chuck and a torque plug-in. By controlling the rotation of the torsion load transmission assembly, a pure torsion load applying mode or a conversion mode of converting torsion motion into radial load can be selectively realized, and multi-directional load detection is realized. The invention further provides a combined load synchronous applying function, the single driving source synchronously activates the torsion load path and the radial load path by adjusting the geometric positions of the torque plug-in and the load adjusting plate on the connecting chuck, and synchronous applying of the torsion load and the radial load is achieved.

The invention discloses a large-deformation tunnel surrounding rock-structure rigidity coordination indoor experiment testing structure, and belongs to the technical field of tunnel structure testing. The testing structure comprises a first reaction frame and a second reaction frame, and the two reaction frames are connected through four steel strands and bolts to form a square frame. Yieldable I-shaped steel, a spring, a longitudinal connecting structure, a yielding component, a surrounding rock simulation system and a jack I are sequentially connected and arranged in the square frame in the direction from the reaction frame I to the reaction frame II; the surrounding rock simulation system comprises two square steel plates and a plurality of square surrounding rock simulators clamped between the two square steel plates; four steel strands penetrate through the four corners of the two square steel plates respectively and are fixedly connected with the second reaction frame, and the two ends of the steel strands are fixed through bolts. The test structure provided by the invention can effectively simulate the stress states of the surrounding rock and the support under the rigidity coordination effect of each support structure in the large-deformation tunnel.

The invention provides a semiconductor device, a cutting method thereof and a semiconductor chip, relates to the technical field of semiconductor chips, and aims to solve the technical problem that the packaging yield of the semiconductor chip is low. The semiconductor device comprises a substrate, a plurality of semiconductor units and a plurality of test structures, wherein the plurality of semiconductor units and the plurality of test structures are located on one side of the substrate. The plurality of semiconductor units are distributed in an array, and at least part of the plurality of test structures is located between two adjacent semiconductor units. In the two adjacent semiconductor units and the test structure between the two adjacent semiconductor units, the distance between one semiconductor unit and the test structure is smaller than the distance between the other semiconductor unit and the test structure. The semiconductor chip obtained by cutting the semiconductor device is applied to a three-dimensional memory so as to realize data reading and writing operation.

The invention relates to the technical field of aero-engine tests, in particular to an aero-engine turbine blade cooling effect test optical test structure which comprises optical glass, an outer casing and an optical channel pipe. The optical glass is located on the light-in side of the optical channel pipe, and the light-out side of the optical channel pipe faces the target blade. The outer casing is arranged on the outer side of the optical channel pipe in a sleeving mode, and a cooling channel is formed between the inner wall of the outer casing and the outer wall of the optical channel pipe so as to cool the optical channel pipe; a gas film ring is connected between the optical glass base and the light inlet side of the optical channel pipe in a sealed mode and located on the light outlet side of the optical glass. The optical glass base is provided with the cooling gas inlet, and the gas film ring is provided with the gas jet hole, so that the cooling gas performs jet sweeping on the light emitting surface of the optical glass and enters the optical channel pipe to cool the optical channel pipe, thereby improving the accuracy of the cooling effect test result of the turbine blade.

The utility model provides a hydraulic safety valve fixed calibration table, and relates to the field of calibration tables. The testing structure is installed on the side edge of the verification table body, the top end of the testing structure is provided with the detection head structure through a fixing disc structure, the detection head structure is sleeved with the sealing structure, the sealing structure is of a circular ring structure, the outer side of the sealing structure made of rubber is of an inclined structure, and an annular through hole is formed in the sealing structure. When the hydraulic safety valve is tested, after being fixed, the hydraulic safety valve is in butt joint with the sealing structure, meanwhile, the hydraulic safety valve is continuously stressed and pressed downwards to extrude the sealing structure, the sealing effect and the sealing strength are improved, even if the sealing structure is abraded or the sealing performance is reduced, the sealing structure is conveniently taken down and replaced, and the replacement efficiency is improved; the problems that according to a common hydraulic safety valve fixed type checking table, after a detection head structure is in butt joint with a hydraulic safety valve for use for many times, abrasion can occur, and the sealing performance can be reduced are solved.

An end effector has an end effector frame configured to be mounted to a movable platform capable of positioning the end effector relative to a structure. In addition, the end effector has a plurality of process tools mounted to the end effector frame and having different functional capabilities associated with hole formation and fastener installation in the structure. Furthermore, the end effector has a continuity tester configured to determine the existence of an uninterrupted electrical path between a fastener and the structure after installation of the fastener.

The invention is suitable for the technical field of solar cells, and provides a back contact solar cell, a cell assembly and a photovoltaic system. The first fine grids and the second fine grids are arranged on the back surface of the silicon substrate; the at least one group of first bonding pads are arranged on the back surface of the silicon substrate, and the first bonding pads are electrically connected with the first fine grids; the at least one group of second bonding pads are arranged on the back surface of the silicon substrate and are electrically connected with the second fine grids; the first test structure comprises two third bonding pads which are arranged at intervals in the first direction, and the third bonding pads are electrically connected with the first fine grids; the third bonding pad and the first bonding pad are the same in size; the second testing structure comprises two fourth bonding pads which are adjacently arranged in the first direction, the fourth bonding pads are electrically connected with the second fine grids, and the fourth bonding pads and the second bonding pads are the same in size. According to the back contact solar cell provided by the invention, the carrier collection effect of the fine grid can be improved, and the printing cost of the back contact solar cell can be reduced.