A vacuum welding furnace capable of realizing rapid welding of semiconductor products

Abstract

The invention discloses a vacuum welding furnace capable of realizing rapid welding of semiconductor products, comprising a base, a furnace body, a welding system, a vacuum system, a nitrogen system, and a water cooling system; the furnace body comprises a furnace chamber with a "mouth"-shaped cross section, a furnace bottom plate capable of sealing the bottom of the furnace chamber, a furnace cover capable of sealing the top of the furnace chamber, a furnace cover opening and closing device, and a sealing device; the opening and closing device comprises an opening cylinder arranged on the left side of the furnace chamber, a hook cylinder arranged in the middle of the right end of the top surface of the furnace cover, and two locking cylinders arranged at the right end of the bottom surface of the furnace bottom plate; the welding system comprises a bracket, a bottom reflection plate, a main graphite heating plate, a graphite boat, a graphite boat support frame, a four-edge graphite heating belt, a four-edge reflection belt, and an electrode. The vacuum welding furnace of the invention has the characteristics of rapid heating and cooling, fast welding speed, reliable vacuum performance, low cooling cost, and easy maintenance.

Description

Technical Field

[0001] The invention relates to semiconductor welding equipment, belonging to the technical field of vacuum welding. Background Art

[0002] In the context of the rapid development of modern integrated circuits and electronic technology, semiconductor products are becoming more and more widely used. With the increasing requirements for the refined quality of semiconductor products, especially semiconductor metal packaging devices and semiconductor ceramic packaging devices, the traditional reflow soldering process, welding quality and void rate can no longer meet the quality requirements of semiconductor products.

[0003] At present, the traditional vacuum reflow oven uses the filament in the heating box to generate hot air and circulate the hot air to heat the circuit board. The heating tube in the heating box heats the air in the box weight, and then the fan is used to transport the hot air to the furnace chamber of the reflow oven. In order to make the air outlet of the heating box uniform, there is a metal rectifier plate at the air outlet of the heating box, and there are many evenly distributed small holes on the rectifier plate to guide the hot air. The welding process of the circuit board on the conveyor belt refers to the circuit board heating the solder paste on the circuit board under the action of hot air, the flux promotes the melting of the solder paste, and finally the temperature of the circuit board is reduced by the action of the cooling fan, the solder paste solidifies, and the welding process is completed. In the welding method of hot air heating, the heat of the circuit board is transferred from the surface to the inside, which makes it easy for the solder paste on the circuit board to produce bubbles during the heating process, and the phenomenon of false soldering occurs when welding, which seriously affects the product quality. According to incomplete statistics, defective products produced in this way account for about 50% of all defective products. Secondly, due to the low efficiency of hot air heat transfer, especially for flexible circuit boards installed with fixtures, the heat absorption is very large. The inefficient heating method directly leads to insufficient heating of the circuit board, local high temperature and other phenomena, which leads to poor welding such as circuit board deformation, seriously affecting the quality of the product; thirdly, the rectifier board itself does not generate heat, and the surface temperature cannot reach the vaporization temperature required by the flux, which makes it easy for the flux to adhere and condense on the rectifier board, making maintenance and cleaning quite difficult. On the other hand, the chamber door of the vacuum reflow furnace has a complex structure and weighs more than 20KG. If it is opened and closed manually, it is difficult for ordinary female operators to complete it independently, let alone realize automated integration. The temperature control method of most vacuum reflow furnaces adopts the integration of temperature sensing element plug-in temperature control and heating plate, and the heating plate is not convenient to disassemble and customize. The vacuum reflow soldering equipment has the following problems: 1. The hot air reflow furnace is used as the heating device, which has the problems of slow heating speed, low maximum heating temperature, uneven heating of the circuit board, resulting in bubbles in the solder paste, resulting in false solder joints, deformation of the circuit board and other poor welding problems; 2. The surface temperature of the rectifier plate is relatively low, which easily causes the flux to adhere and condense, making maintenance and cleaning difficult; 3. The infrared welding technology used in the prior art is convenient for heat source control, but there are problems such as the shielding of the photosensitivity point, the different quality of components and PCBs affecting the heating effect, and large temperature difference; 4. The long-term use of the cavity cover thread is prone to secondary pollution and reduced particle size. In addition, the general threaded door lock device is made of thin materials and is easily deformed by external impact and cannot be used, and has poor durability. In addition, the cavity cover is too heavy and inconvenient for female operators to operate; 5. The temperature control method in the prior art adopts a plug-in heating plate, which is not convenient for disassembly. 6. During the welding process, the bottom and side walls of the furnace body made of metal must be relatively thick due to frequent cooling and heating. Otherwise, small cracks that are difficult to find will easily appear between the bottom and side walls of the furnace body, affecting the welding quality. However, the thickness of the bottom and side walls of the furnace body will delay the welding heating process and consume more energy.

[0004] The patent with the publication number CN11175964A discloses an automatic vacuum reflow soldering equipment with contact temperature control, including a heating chamber, a chamber cover forming a sealed chamber with the heating chamber, a plurality of infrared radiation tubes installed in the heating chamber, a heating plate located above the infrared radiation tubes, a contact temperature control mechanism, a vacuum pumping mechanism and a cooling mechanism connected to the heating chamber. The heating chamber and the chamber cover are both made of quartz glass. One end of the chamber cover is hingedly mounted on the heating chamber, and the other end is detachably sealed and mounted with the heating chamber through an automatic opening and closing hook lock device, which is used to isolate the internal and external air and ensure that the vacuum state in the heating chamber is not affected. A protruding sealing strip is installed on the upper surface of the heating chamber. A heating chamber is arranged in the heating chamber, and a plurality of infrared radiation tubes are installed in the heating chamber. The outstanding defects of this technology are that the heating chamber is installed on the cylinder tail support and the heating chamber is fixedly installed on the upper surface of a large volume bottom plate. The heating chamber and the chamber cover are both made of quartz glass. When cooling is required, the heating chamber and the chamber cover have a large specific heat and a slow cooling speed, which delays the cooling speed during welding and prolongs the welding time. During cooling, nitrogen needs to be passed through the cooling gas nozzle for cooling, but the cost of using cooling gas for cooling is high; due to the use of infrared radiation tubes, their corrosion resistance is poor, and after cooling, formic acid is passed through the reducing gas nozzle to reduce the gas inside the heating chamber; although the surface of the heating plate is coated with an optical coating to facilitate heat radiation, it is still difficult to ensure uniform heat distribution during the entire heating process.

[0005] For the small reflow soldering furnace in the prior art, the entire reflow soldering process is generally realized within a cavity space. Each soldering operation requires heating from room temperature to the soldering temperature and then cooling from the soldering temperature to room temperature. For multiple soldering operations, multiple temperature thermal shocks are required. First, frequent heating and cooling result in a large amount of energy loss; second, this causes temperature stress to the reflow soldering equipment itself, leading to fatigue damage; third, heating and cooling take a lot of time, reducing the soldering efficiency. For the large and medium-sized reflow soldering furnaces in the prior art, multi-zone soldering is generally adopted, which is divided into a preheating zone, a heat preservation zone, a soldering zone, and a cooling zone, and pipeline operation is adopted during the soldering process. However, the heating zone and the cooling zone are connected, and the hot and cold air will affect or mix with each other, which has an adverse effect on obtaining a hot environment or a cold environment originally desired. This also affects the heating and cooling temperature fields and causes a certain amount of energy loss. Therefore, for the vacuum reflow soldering furnace with the existing structure, since most of them use infrared radiation tubes to radiate for heat transfer, the convective heat transfer is not strong or there is no convective heat transfer, and there are disadvantages such as slow radiation heating heat transfer and low efficiency. Moreover, it is difficult for these structures to perform reflow soldering in a vacuum or protective atmosphere because the loading and unloading of the workpieces to be soldered in pipeline soldering cannot ensure that the soldering equipment forms a vacuum environment and a protective atmosphere environment. In this case, it is necessary to develop a reflow soldering furnace that can adopt other heating methods and conveniently achieve vacuum or protective atmosphere through structural configuration. Summary of the Invention

[0006] The purpose of the present invention is to provide a vacuum soldering furnace capable of realizing rapid soldering of semiconductor products, aiming at the deficiencies of the prior art, which has the characteristics of rapid heating and cooling, fast soldering speed, reliable vacuum performance, low cooling cost, and easy maintenance.

[0007] The technical solution adopted by the present invention is as follows.

[0008] A vacuum soldering furnace capable of realizing rapid soldering of semiconductor products includes a base, a furnace body, a soldering system, a vacuum system, a nitrogen system, and a water cooling system.

[0009] The furnace body includes a furnace chamber with a "mouth"-shaped cross-section, a furnace bottom plate that can seal the bottom of the furnace chamber, a furnace cover that can seal the top of the furnace chamber, a furnace cover opening and closing device, and a sealing device; the left end of the furnace cover is hinged to the top of the left side surface of the furnace chamber through a first hinge longitudinal axis, and an upper sealing strip in the shape of a "mouth" is provided at the joint of the furnace cover and the furnace chamber; the left end of the furnace bottom plate is hinged to the bottom of the left side surface of the furnace chamber through a second hinge longitudinal axis, and a lower sealing strip in the shape of a "mouth" is provided at the joint of the furnace bottom plate and the furnace chamber; the furnace chamber, the furnace bottom plate, and the furnace cover are all made of metal materials; the furnace bottom plate is arranged on the base.

[0010] The furnace cover opening and closing device includes a cover opening cylinder arranged on the left side of the furnace chamber, a hook cylinder arranged in the middle of the right end of the top surface of the furnace cover, and two locking cylinders arranged at the right end of the bottom surface of the furnace bottom plate; the output shaft of the cover opening cylinder, the output shaft of the hook cylinder, and the output shaft of the locking cylinder are all located on the plane perpendicular to the first hinged longitudinal axis; an ear plate is provided at the left end of the top surface of the furnace cover, and the top end of the cover opening cylinder is hinged to the ear plate through the third hinged longitudinal axis.

[0011] Two upper hook devices are symmetrically arranged along the hook cylinder at the right end of the furnace cover, each upper hook device includes a fourth hinged longitudinal axis, an upper rotating plate mounted on the fourth hinged longitudinal axis, and a hook with an opening facing left is arranged at the bottom of the upper rotating plate; the top ends of the two upper rotating plates are connected by a top longitudinal rod; the top longitudinal rod is hinged to the upper end of the hook cylinder.

[0012] A fifth hinged longitudinal axis is provided at the right end of the furnace bottom plate; two lower hook devices are symmetrically provided along the hook cylinder at the right end of the furnace cover; each lower hook device comprises a fifth hinged longitudinal axis, two lower rotating plates mounted on the fifth hinged longitudinal axis, and a hanging rod is provided on the top of each lower rotating plate; the bottom end of each lower rotating plate is hinged to a locking cylinder; when the furnace cover is fitted with the furnace chamber, the rotation of the two upper rotating plates is controlled by the cover opening cylinder, and the rotation of the two lower rotating plates is controlled by the two locking cylinders, so that the hanging rod of each lower rotating plate can enter the hook of the upper rotating plate above it.

[0013] The welding system comprises a bracket, a bottom reflection plate, a main graphite heating plate, a graphite boat, a graphite boat support frame, four-edge graphite heating belts, four-edge reflection belts, and electrodes; the main graphite heating plate, the graphite boat support frame, and the graphite boat are installed on the bracket from bottom to top; the bottom reflection plate is arranged below the main graphite heating plate, and there is no contact between the top surface of the bottom reflection plate and the bottom surface of the main graphite heating plate, and between the top surface of the main graphite heating plate and the bottom surface of the graphite boat support frame; each edge reflection belt is respectively installed on an inner side wall of the furnace, and each edge graphite heating belt is respectively installed on the inner side of an edge reflection belt.

[0014] The bottom reflector is installed on the furnace bottom plate; the bracket is installed on the bottom reflector; the main graphite heating plate and each edge graphite heating belt are connected with the electrode arranged on the furnace; and a plurality of graphite boat heat dissipation holes are arranged on the graphite boat.

[0015] The vacuum system comprises a vacuum pumping tube arranged on the furnace, and the vacuum pumping tube is connected to a vacuum pumping device arranged outside the furnace body.

[0016] The nitrogen system comprises a nitrogen inlet and outlet pipe arranged on the furnace, and the nitrogen inlet and outlet pipe is connected to a nitrogen pumping device arranged outside the furnace body.

[0017] The water cooling system comprises a plurality of furnace cooling channels respectively arranged on each side wall of the furnace, a plurality of furnace cover cooling channels arranged on the furnace cover, a plurality of furnace bottom plate cooling channels arranged on the furnace bottom plate, a coil groove arranged on the bottom surface of the graphite boat and a coil arranged on the coil groove; the bottom surface of each coil groove is in contact with the graphite boat support frame; the coil passes through the furnace and is connected to a coolant pumping device and a coolant tank arranged outside the furnace body; the inlet and outlet of each furnace cooling channel, furnace cover cooling channel and furnace bottom plate cooling channel are respectively connected to the coolant pumping device and the coolant tank arranged outside the furnace body through pipelines.

[0018] As a preferred technical solution, a hanging rod movable groove is provided at the top of each lower rotating plate, and a hanging rod is provided in the hanging rod movable groove, and the hanging rod can move up and down in the hanging rod movable groove.

[0019] As an optimal technical solution, the lower rotating plate includes a lower tooth plate and an upper tooth plate which are fixedly connected; a hanging rod mounting frame is provided at the top of the upper tooth plate, and the hanging rod mounting frame includes a bottom panel and two vertical plates, and the two vertical plates are symmetrically arranged along the upper rotating plate closest to it; each vertical plate is provided with a hanging rod movable groove, and the two ends of the hanging rod are respectively located in the hanging rod movable grooves of the two vertical plates.

[0020] As a preferred technical solution, the edge reflection band includes an edge reflection band body made of metal, and an edge reflection band coating is provided on the inner side of the edge reflection band body; the bottom reflection disk includes a bottom reflection disk body made of metal, and a bottom reflection disk coating is provided on the inner side of the bottom reflection disk body.

[0021] As a preferred technical solution, the edge reflection band coating is an edge reflection band coating made of silver; and the bottom reflection disk coating is a bottom reflection disk coating made of silver.

[0022] As a preferred technical solution, the top surface of the furnace body is provided with an upper sealing strip installation groove for installing the upper sealing strip, and the bottom surface of the furnace body is provided with a lower sealing strip installation groove for installing the lower sealing strip.

[0023] As an optimal technical solution, the bracket includes a central bracket and several edge brackets. A central through hole is provided in the center of the main graphite heating plate. Steps for placing the main graphite heating plate are provided on the central bracket and the edge brackets. The central bracket passes through the central through hole of the main graphite heating plate; the top ends of the edge bracket and the central bracket are connected to the graphite boat support frame.

[0024] As a preferred technical solution, the main graphite heating plate includes three graphite strips with terminal ends, and the graphite strips are spirally arranged around the central through hole.

[0025] As an optimal technical solution, a welding tool is placed on the graphite ship, and the parts to be welded are placed in the welding tool; the welding tool is made of graphite; the furnace, furnace cover and furnace bottom plate are made of aluminum.

[0026] As a preferred technical solution, the lower end of the hook cylinder is hinged to the furnace cover through the seventh hinged longitudinal axis; the bottom end of the cover opening cylinder is hinged to the base through the eighth hinged longitudinal axis; the bottom end of each lower rotating plate is hinged to the right end of a locking cylinder through the ninth hinged longitudinal axis. The four corners of the furnace bottom plate are mounted on the base through four insulation columns.

[0027] The invention has the beneficial effects that the opening and closing device comprises an opening cylinder arranged on the left side of the furnace, a hook cylinder arranged in the middle of the right end of the top surface of the furnace cover, and two locking cylinders arranged on the right end of the bottom surface of the furnace bottom plate. The opening cylinder, the hook cylinder, and the two locking cylinders cooperate with each other. The top of the lower rotating plate is provided with a hanging rod movable groove. When the hanging rod is hung in the hook of the upper rotating plate, it is reliably hung and has a good sealing effect. The furnace, the furnace bottom plate, and the furnace cover of the furnace body are made of split metal and can withstand large pressure. The furnace, the furnace bottom plate, and the furnace cover are all provided with a cooling liquid channel, and the furnace, the furnace bottom plate, and the furnace cover are quickly heated and cooled; the furnace, the furnace bottom plate, and the furnace cover are connected by the opening and closing device. After the furnace, the furnace bottom plate, and the furnace cover are used for a period of time, the sealing effectiveness can be achieved by replacing the upper sealing strip and the lower sealing strip, which solves the problem that when the furnace and the furnace bottom plate are integrally cast in the prior art, the welding part between the furnace and the furnace bottom plate is difficult to repair once the leakage phenomenon may occur under the pressure change of long-term use. Two locking cylinders are set and symmetrically distributed along the hook cylinder. The right side of the furnace has a good sealing effect and occupies a small volume for opening and installation. The bottom of the main graphite heating plate is used for radiation heating, and the edge graphite heating belt is used for radiation heating around the graphite boat. The bottom reflector plate and the edge reflector belt are used for reflection. The heating speed is fast, the corrosion resistance is good, the deformation is small, and the heating is uniform. Once the heating is completed, the main graphite heating plate is directly cooled by coolant. Since the furnace, the bottom plate and the cover are all made of metal, the heat dissipation is fast, the welding time is short, the welding speed is fast, and the welding effect is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a three-dimensional structural schematic diagram of the vacuum welding furnace of the present invention. Figure 2 yes Figure 1 A partial enlarged view of part A. Figure 3 yes Figure 1 A partial enlarged view of part B. Figure 4 yes Figure 3 A partial enlarged view of part C. Figure 5 yes Figure 3 A partial enlarged view of part D. Figure 6 yes Figure 1 Left side view of the vacuum welding furnace shown. Figure 7 yes Figure 1 Rear view of the vacuum soldering furnace shown. Figure 8 yes Figure 1 A top view of a vacuum soldering furnace is shown. Fig. 9 yes Figure 1 A front view of a vacuum soldering furnace is shown. Fig.10 yes Fig. 9 A partial enlarged view of part E. Fig.11 yes Figure 8 A cross-sectional view of the vacuum welding furnace along line FF' is shown. Fig.12 yes Figure 8 The cross-sectional view of the vacuum welding furnace along line G-G' is shown. Fig.13 yes Fig.11 A partial enlarged view of part H. Fig.14 yes Fig.11 A partial enlarged view of part I. Fig.15 yes Fig.12 A partial enlarged view of part K. Fig.16 yes Fig.12 A partial enlarged view of the L part. Fig.17 yes Fig.12 The cross-sectional view of the vacuum welding furnace along the J-J' line is shown. Fig.18 yes Figure 1 Schematic diagram of the main graphite heating plate of the vacuum welding furnace installed on the bottom reflection plate. Fig.19 yes Fig.17 A partial enlarged view of part M. Fig. 20 yes Figure 1 The schematic diagram of the structure of the vacuum welding furnace is shown when the four-edge graphite heating belts are connected. Fig.21 yes Figure 1 Schematic diagram of the structure of the main graphite heating plate of the vacuum welding furnace shown. Fig. 22 It is a three-dimensional structural diagram of the coil installed on the graphite ship. Fig.23 yes Fig. 22 Bottom view of the structure shown. Fig.24 yes Figure 1 Top view of the graphite boat of the vacuum welding furnace shown. Fig.25 yes Figure 1 Left side view of the graphite boat of the vacuum welding furnace shown. Fig.26 yes Figure 1 A three-dimensional perspective view of the furnace chamber of the vacuum welding furnace is shown. Fig. 27 yes Figure 1 A three-dimensional schematic diagram of the furnace body of the vacuum welding furnace shown. Fig.28 yes Fig. 27 A partial enlarged view of part O. Fig.29 yes Fig. 27 Bottom view of the furnace body shown. Fig.30 yes Fig. 27 The furnace body is shown in the state when the furnace cover is opened.

[0029] Among them: base-1; furnace body-2; furnace chamber-21; furnace bottom plate-22; furnace cover-23; first hinged longitudinal axis-24; upper sealing strip-25; lower sealing strip-26; second hinged longitudinal axis-27; opening and closing device-3; cover opening cylinder-31; hook cylinder-32; locking cylinder-33; ear plate-34; third hinged longitudinal axis-35; upper hook device-36; fourth hinged longitudinal axis-37; upper rotating plate-38; top longitudinal rod-310; lower hook device-311; lower hook device-311; fifth hinged longitudinal axis-312; lower rotating plate-313; hanging rod-314; hanging rod movable groove-315; seventh hinged longitudinal axis-316; eighth hinged longitudinal axis-317; ninth hinged longitudinal axis -318; lower tooth plate-319; upper tooth plate-320; hanging rod mounting frame-321; vertical plate-322; bottom panel-323; bracket-41; edge bracket-411; center bracket-412; bottom reflector-42; main graphite heating plate-43; center through hole-431; graphite boat-44; graphite boat heat dissipation hole-441; coil groove-442; graphite boat support frame-45; edge graphite heating belt-46; edge reflector-47; electrode-48; vacuum tube-5; nitrogen inlet and outlet pipe-6; insulation column-7; furnace cooling channel-71; furnace cover cooling channel-72; furnace bottom plate cooling channel-73; coil-74; welding tooling-8; coolant pipe inlet and outlet hole-9. DETAILED DESCRIPTION

[0030] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0031] Example 1. Figure 1-30 As shown, a vacuum welding furnace capable of realizing rapid welding of semiconductor products comprises a base 1, a furnace body 2, a welding system, a vacuum system, a nitrogen system, and a water cooling system.

[0032] The furnace body 2 includes a furnace chamber 21 with a "mouth"-shaped cross-section, a furnace bottom plate 22 that can seal the bottom of the furnace chamber 21, a furnace cover 23 that can seal the top of the furnace chamber 21, a furnace cover opening and closing device 3, and a sealing device; the left end of the furnace cover 23 is hinged to the top of the left side surface of the furnace chamber 21 through a first hinge longitudinal axis 24, and an upper sealing strip 25 in the shape of a "mouth" is provided at the joint of the furnace cover 23 and the furnace chamber 21; the left end of the furnace bottom plate 22 is hinged to the bottom of the left side surface of the furnace chamber 21 through a second hinge longitudinal axis 27, and a lower sealing strip 26 in the shape of a "mouth" is provided at the joint of the furnace bottom plate 22 and the furnace chamber 21; the furnace chamber 21, the furnace bottom plate 22, and the furnace cover 23 are all made of metal materials; the furnace bottom plate 22 is arranged on the base 1. The furnace cover opening and closing device 3 includes an opening cylinder 31 arranged on the left side of the furnace chamber 21, a hook cylinder 32 arranged in the middle of the right end of the top surface of the furnace cover 23, and two locking cylinders 33 arranged at the right end of the bottom surface of the furnace bottom plate 22; the planes where the output shafts of the opening cylinder 31, the hook cylinder 32, and the locking cylinder 33 are located are all perpendicular to the first hinge longitudinal axis 24; an ear plate 34 is provided at the left end of the top surface of the furnace cover 23, and the top end of the opening cylinder 31 is hinged to the ear plate 34 through a third hinge longitudinal axis 35.

[0033] Two upper hook devices 36 are symmetrically arranged along the hook cylinder 32 at the right end of the furnace cover 23. Each upper hook device 36 includes a fourth hinge longitudinal axis 37 and an upper rotating plate 38 sleeved on the fourth hinge longitudinal axis 37. A hook 39 with an opening to the left is provided at the bottom of the upper rotating plate 38; the tops of the two upper rotating plates 38 are connected by a top longitudinal rod 310; the top longitudinal rod 310 is hinged to the upper end of the hook cylinder 32. A fifth hinge longitudinal axis 312 is provided at the right end of the furnace bottom plate 22; two lower hook devices 311 are symmetrically arranged along the hook cylinder 32 at the right end of the furnace cover 23; each lower hook device 311 includes a fifth hinge longitudinal axis 312 and two lower rotating plates 313 sleeved on the fifth hinge longitudinal axis 312. A hanging rod 314 is provided at the top of each lower rotating plate 313; the bottom end of each lower rotating plate 313 is hinged to a locking cylinder 33; when the furnace cover 23 is attached to the furnace chamber 21, by controlling the rotation of the two upper rotating plates 38 through the opening cylinder 31 and controlling the rotation of the two lower rotating plates 313 through the two locking cylinders 33, the hanging rods 314 of the lower rotating plates 313 can be made to enter the hooks 39 of the upper rotating plates 38 above them.

[0034] The welding system includes a bracket 41, a bottom reflection plate 42, a main graphite heating plate 43, a graphite boat 44, a graphite boat support frame 45, four-edge graphite heating belts 46, four-edge reflection belts 47, and an electrode 48; the main graphite heating plate 43, the graphite boat support frame 45, and the graphite boat 44 are installed on the bracket 41 from bottom to top; the bottom reflection plate 42 is arranged below the main graphite heating plate 43, and there is no contact between the top surface of the bottom reflection plate 42 and the bottom surface of the main graphite heating plate 43, and between the top surface of the main graphite heating plate 43 and the bottom surface of the graphite boat support frame 45; each edge reflection belt 47 is respectively installed on an inner side wall of the furnace 21, and each edge graphite heating belt 46 is respectively installed on the inner side of an edge reflection belt 47. The bottom reflector 42 is mounted on the furnace bottom plate 22; the bracket 41 is mounted on the bottom reflector 42; the main graphite heating plate 43 and the edge graphite heating belts 46 are connected to the electrode 48 arranged on the furnace 21; the graphite boat 44 is provided with a plurality of graphite boat heat dissipation holes 441. The vacuum system includes a vacuum pumping tube 5 arranged on the furnace 21, and the vacuum pumping tube 5 is connected to a vacuum pumping device arranged outside the furnace body 2.

[0035] The nitrogen system includes a nitrogen inlet and outlet pipe 6 arranged on the furnace 21, and the nitrogen inlet and outlet pipe 6 is connected to a nitrogen pumping device arranged outside the furnace body 2. The water cooling system includes a plurality of furnace cooling channels 71 respectively arranged on each side wall of the furnace 21, a plurality of furnace cover cooling channels 72 arranged on the furnace cover 23, a plurality of furnace bottom plate cooling channels 73 arranged on the furnace bottom plate 22, a coil groove 442 arranged on the bottom surface of the graphite boat 44, and a coil 74 arranged on the coil groove 442; the bottom surface of each coil groove 442 is in contact with the graphite boat support frame 45; the coil 74 passes through the furnace 21 and is connected to a coolant pumping device and a coolant tank arranged outside the furnace body 2; the inlet and outlet of each furnace cooling channel 71, furnace cover cooling channel 72, and furnace bottom plate cooling channel 73 are respectively connected to the coolant pumping device and the coolant tank arranged outside the furnace body 2 through pipelines. Each furnace cooling channel 71, furnace cover cooling channel 72, furnace bottom plate cooling channel 73 is a spiral pipe; a water hammer eliminator is provided on the pipeline between each furnace cooling channel 71, furnace cover cooling channel 72, furnace bottom plate cooling channel 73 and the coolant pumping device arranged outside the furnace body. A hanging rod movable groove 315 is provided at the top of each lower rotating plate 313, and a hanging rod 314 is provided in the hanging rod movable groove 315, and the hanging rod 314 can move up and down in the hanging rod movable groove 315.

[0036] like Figure 9-10As shown, the lower rotating plate 313 includes a lower tooth plate 319 and an upper tooth plate 320 which are fixedly connected; a hanging rod mounting frame 321 is provided at the top of the upper tooth plate 320, and the hanging rod mounting frame 321 includes a bottom plate 323 and two vertical plates 322, and the two vertical plates 322 are symmetrically arranged along the upper rotating plate closest thereto; each vertical plate 322 is provided with a hanging rod movable groove 315, and the two ends of the hanging rod 314 are respectively located in the hanging rod movable grooves 315 of the two vertical plates 322. The edge reflection band 47 includes an edge reflection band body made of metal, and an edge reflection band coating is provided on the inner side surface of the edge reflection band body; the bottom reflection disk 42 includes a bottom reflection disk body made of metal, and a bottom reflection disk coating is provided on the inner side surface of the bottom reflection disk body. The edge reflection band coating is an edge reflection band coating made of silver; and the bottom reflection disk coating is a bottom reflection disk coating made of silver.

[0037] The top surface of the furnace body 2 is provided with an upper sealing strip installation groove for installing the upper sealing strip 25, and the bottom surface of the furnace body 2 is provided with a lower sealing strip installation groove for installing the lower sealing strip 26. The bracket 41 includes a central bracket 412 and a plurality of edge brackets 411. The center of the main graphite heating plate 43 is provided with a central through hole 431. The central bracket 412 and the edge bracket 411 are provided with steps for placing the main graphite heating plate 43. The central bracket 412 passes through the central through hole 431 of the main graphite heating plate 43; the top ends of the edge brackets 411 and the central bracket 412 are connected to the graphite boat support frame 45. The main graphite heating plate 43 includes a graphite belt with three terminal ends, and the graphite belt is spirally arranged around the central through hole 431. The thickness of the furnace cover is 80mm, and the thickness of the furnace chamber and the furnace bottom plate is 350mm. The maximum heating temperature is 500℃, and the maximum heating speed can reach 220℃ / min; when nitrogen is not used for cooling, the cooling speed can reach 120℃ / min. Graphite electric heating uses isostatic high-purity graphite with excellent thermal conductivity to ensure temperature uniformity between points, with a temperature difference of less than ±1.5°C between samples. The temperature control PID parameter self-checking can adjust the heating rate, with a temperature control accuracy of ±0.1°C and a temperature fluctuation of ±1.0°C at each point. The bottom surface of the graphite strip is parallel to the ground.

[0038] A welding tool 8 is placed on the graphite boat 44, and the parts to be welded are placed in the welding tool 8; the welding tool 8 is made of graphite; the furnace 21, the furnace cover 23, and the furnace bottom plate 22 are made of aluminum. The main graphite heating plate 43, the graphite boat 44, the graphite boat support frame 45, the edge graphite heating belt 46, etc. are made of anti-corrosion graphite heat-conducting materials, and the surface is sprayed with Teflon to resist strong acid and alkali corrosion. The whole machine is anti-corrosion sprayed to ensure the normal operation of the instrument in an acid environment.

[0039] The lower end of the hook cylinder 32 is hinged to the furnace cover 23 through the seventh hinged longitudinal axis 316; the bottom end of the cover opening cylinder 31 is hinged to the base 1 through the eighth hinged longitudinal axis 317; the bottom end of each lower rotating plate 313 is hinged to the right end of a locking cylinder 33 through the ninth hinged longitudinal axis 318. The four corners of the furnace bottom plate 22 are mounted on the base 1 through four insulation columns 7. The furnace 21 is provided with a coolant pipe inlet and outlet hole 9, and the coil passes through the coolant pipe inlet and outlet hole 9.

Claims

1. A vacuum soldering furnace capable of realizing rapid soldering of semiconductor products, comprising a base, a furnace body, a soldering system, a vacuum system, a nitrogen system, and a water cooling system, characterized in that: The furnace body includes a furnace chamber with a "mouth"-shaped cross-section, a furnace bottom plate capable of sealing the bottom of the furnace chamber, a furnace cover capable of sealing the top of the furnace chamber, a furnace cover opening and closing device, and a sealing device; the left end of the furnace cover is hinged to the top of the left side surface of the furnace chamber through a first hinged longitudinal axis, and an upper sealing strip in the shape of a "mouth" is provided at the joint of the furnace cover and the furnace chamber; the left end of the furnace bottom plate is hinged to the bottom of the left side surface of the furnace chamber through a second hinged longitudinal axis, and a lower sealing strip in the shape of a "mouth" is provided at the joint of the furnace bottom plate and the furnace chamber; the furnace chamber, the furnace bottom plate, and the furnace cover are all made of metal materials; the furnace bottom plate is arranged on the base; The furnace cover opening and closing device includes an opening cylinder arranged on the left side of the furnace chamber, a hook cylinder arranged in the middle of the right end of the top surface of the furnace cover, and two locking cylinders arranged at the right end of the bottom surface of the furnace bottom plate; the planes where the output shafts of the opening cylinder, the hook cylinder, and the locking cylinders are located are all perpendicular to the first hinged longitudinal axis; an ear plate is provided at the left end of the top surface of the furnace cover, and the top end of the opening cylinder is hinged to the ear plate through a third hinged longitudinal axis; Two upper hook devices are symmetrically arranged along the hook cylinder at the right end of the furnace cover. Each upper hook device includes a fourth hinged longitudinal axis and an upper rotating plate sleeved on the fourth hinged longitudinal axis. A hook with an opening to the left is provided at the bottom of the upper rotating plate; the tops of the two upper rotating plates are connected by a top longitudinal rod; the top longitudinal rod is hinged to the upper end of the hook cylinder; A fifth hinged longitudinal axis is provided at the right end of the furnace bottom plate; two lower hook devices are symmetrically arranged along the hook cylinder at the right end of the furnace cover; each lower hook device includes a fifth hinged longitudinal axis and two lower rotating plates sleeved on the fifth hinged longitudinal axis. A hanging rod is provided at the top of each lower rotating plate; the bottom end of each lower rotating plate is hinged to a locking cylinder; when the furnace cover fits with the furnace chamber, by controlling the rotation of the two upper rotating plates through the opening cylinder and controlling the rotation of the two lower rotating plates through the two locking cylinders, the hanging rods of the lower rotating plates can enter the hooks of the upper rotating plates above them; The soldering system includes a bracket, a bottom reflector, a main graphite heating plate, a graphite boat, a graphite boat support frame, four edge graphite heating belts, four edge reflector belts, and electrodes; the main graphite heating plate, the graphite boat support frame, and the graphite boat are installed on the bracket from bottom to top; the bottom reflector is arranged below the main graphite heating plate, and there is no contact between the top surface of the bottom reflector and the bottom surface of the main graphite heating plate and between the top surface of the main graphite heating plate and the bottom surface of the graphite boat support frame; each edge reflector belt is respectively installed on an inner side wall of the furnace chamber, and each edge graphite heating belt is respectively installed on the inner side of an edge reflector belt; The bottom reflector is installed on the furnace bottom plate; the bracket is installed on the bottom reflector; the main graphite heating plate and each edge graphite heating belt are connected to the electrodes arranged on the furnace chamber; a plurality of graphite boat heat dissipation holes are provided on the graphite boat; The vacuum system includes a vacuum extraction pipe arranged on the furnace chamber, and the vacuum extraction pipe is connected to a vacuum extraction device arranged outside the furnace body; The nitrogen system includes a nitrogen inlet and outlet pipe arranged on the furnace chamber, and the nitrogen inlet and outlet pipe is connected to a nitrogen pumping device arranged outside the furnace body; The water cooling system comprises a plurality of furnace cooling channels respectively arranged on each side wall of the furnace, a plurality of furnace cover cooling channels arranged on the furnace cover, a plurality of furnace bottom plate cooling channels arranged on the furnace bottom plate, a coil groove arranged on the bottom surface of the graphite boat and a coil arranged on the coil groove; the bottom surface of each coil groove is in contact with the graphite boat support frame; the coil passes through the furnace and is connected to a coolant pumping device and a coolant tank arranged outside the furnace body; the inlet and outlet of each furnace cooling channel, furnace cover cooling channel and furnace bottom plate cooling channel are respectively connected to the coolant pumping device and the coolant tank arranged outside the furnace body through pipelines; A welding tool is placed on the graphite ship, and the parts to be welded are placed in the welding tool; the welding tool is made of graphite; the furnace, furnace cover and furnace bottom plate are made of aluminum; The lower end of the hook cylinder is hinged to the furnace cover through the seventh hinged longitudinal axis; the bottom end of the cover opening cylinder is hinged to the base through the eighth hinged longitudinal axis; the bottom end of each lower rotating plate is hinged to the right end of a locking cylinder through the ninth hinged longitudinal axis; the four corners of the furnace bottom plate are installed on the base through four insulation columns.

2. A vacuum welding furnace capable of realizing rapid welding of semiconductor products as claimed in claim 1, characterized in that: A hanging rod movable groove is arranged on the top of each lower rotating plate, and a hanging rod is arranged in the hanging rod movable groove, and the hanging rod can move up and down in the hanging rod movable groove.

3. A vacuum welding furnace capable of realizing rapid welding of semiconductor products as claimed in claim 2, characterized in that: The lower rotating plate includes a lower tooth plate and an upper tooth plate which are fixedly connected; a hanging rod mounting frame is provided at the top of the upper tooth plate, and the hanging rod mounting frame includes a bottom panel and two vertical plates, and the two vertical plates are symmetrically arranged along the upper rotating plate closest to it; each vertical plate is provided with a hanging rod movable groove, and the two ends of the hanging rod are respectively located in the hanging rod movable grooves of the two vertical plates.

4. A vacuum welding furnace capable of realizing rapid welding of semiconductor products as claimed in claim 1, characterized in that: The edge reflection band comprises an edge reflection band body made of metal, and an edge reflection band coating is arranged on the inner side of the edge reflection band body; the bottom reflection dish comprises a bottom reflection dish body made of metal, and a bottom reflection dish coating is arranged on the inner side of the bottom reflection dish body.

5. A vacuum welding furnace capable of realizing rapid welding of semiconductor products as claimed in claim 4, characterized in that: The edge reflection band coating is an edge reflection band coating made of silver; the bottom reflection plate coating is a bottom reflection plate coating made of silver.

6. A vacuum welding furnace capable of realizing rapid welding of semiconductor products as claimed in claim 1, characterized in that: The top surface of the furnace body is provided with an upper sealing strip installation groove for installing the upper sealing strip, and the bottom surface of the furnace body is provided with a lower sealing strip installation groove for installing the lower sealing strip.

7. A vacuum welding furnace capable of realizing rapid welding of semiconductor products as claimed in claim 6, characterized in that: The bracket includes a central bracket and several edge brackets. A central through hole is provided in the center of the main graphite heating plate. Steps for placing the main graphite heating plate are provided on the central bracket and the edge brackets. The central bracket passes through the central through hole of the main graphite heating plate. The top ends of the edge brackets and the central bracket are connected to the graphite boat support frame.

8. A vacuum welding furnace capable of realizing rapid welding of semiconductor products as claimed in claim 7, characterized in that: The main graphite heating plate includes three graphite strips with terminal ends, and the graphite strips are spirally arranged around a central through hole.

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