Multi-crucible evaporation source

Abstract

The invention relates to a multi-crucible evaporation source, and relates to the technical field of evaporation sources, the multi-crucible evaporation source comprises a crucible table, a first screw rod, a water cooling assembly and a flange, the water cooling assembly comprises a water cooling pipe, and the water cooling pipe penetrates through the flange and then extends into the crucible table from a preformed hole in the bottom of the crucible table; the crucible table is used for mounting a plurality of crucibles, and one side of the crucible table is provided with an openable side cover, so that the water cooling pipe is detachably mounted in the crucible table through the openable side cover; the crucible table is detachably connected with the flange through the first screw rod; and the water cooling pipe is detachably connected with the crucible table and the flange. By arranging the detachable water-cooling pipe, the flange, the crucible table and the water-cooling pipe can be separated, so that water-cooling pipes with different lengths can be directly replaced when different evaporation distances are used, tedious disassembly and assembly are avoided, and the use scene of the evaporation source is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of evaporation sources, and particularly to a multi-crucible evaporation source. Background Art

[0002] Molecular beam epitaxy is a method for epitaxial growth of single-crystal thin films. Specifically, by heating a solid material source to sublime it and depositing it on a target to form a single-crystal thin film, this method is widely used in the manufacture of semiconductor devices. In the prior art, when it is necessary to replace the evaporation source to meet different evaporation distances, it is necessary to disassemble the filament and thermocouple together. This disassembly and installation are relatively cumbersome, so a multi-crucible evaporation source is proposed. Summary of the Invention

[0003] The present invention provides a multi-crucible evaporation source to solve the problem that the entire evaporation source needs to be disassembled due to replacing the evaporation distance in the traditional method, and the disassembly and installation are relatively troublesome.

[0004] The present invention provides a multi-crucible evaporation source, including a crucible table, a first screw, a water-cooling component and a flange. Among them,

[0005] The water-cooling component includes a water-cooling pipe, and the water-cooling pipe passes through the flange and extends into the crucible table through a reserved hole at the bottom of the crucible table;

[0006] The crucible table is used to install a plurality of the crucibles. One side of the crucible table is provided with an openable side cover, so that the water-cooling pipe can be detachably installed into the interior of the crucible table through the openable side cover;

[0007] The crucible table and the flange are detachably connected by the first screw;

[0008] The water-cooling pipe is detachably connected to the crucible table and the flange.

[0009] In one embodiment, a notch is provided on one side of the reserved hole close to the side cover. The notch is used to take out the water-cooling pipe from the reserved hole. After the water-cooling pipe passes through the notch and the side cover, it can be separated from the crucible table.

[0010] In one embodiment, the water-cooling component further includes a water inlet pipe and a water outlet pipe installed on the flange. Both ends of the water-cooling pipe pass through the flange and are respectively detachably connected to the water inlet pipe and the water outlet pipe.

[0011] In one embodiment, heating pipes are sleeved on the outer peripheries of a plurality of the crucibles. A base is provided at the bottom of the crucible and the heating pipe. The crucible, the heating pipe and the base are together placed into corresponding crucible holes on the crucible table.

[0012] In one embodiment, a first thermocouple is passed through the center of the base. After passing through the small hole at the bottom of the crucible table, the first thermocouple is connected to one end of a second thermocouple mounted on the flange, and the other end of the second thermocouple is connected to a control system for temperature monitoring.

[0013] In one embodiment, the lead wire of the heating tube passes through the bottom of the crucible table and is connected to one end of a filament. The other end of the filament is connected to one end of an electrode. The electrode is mounted on the flange, and the other end of the electrode is connected to the control system.

[0014] In one embodiment, a rotary introducer is further provided on the flange. The rotary introducer is connected to one end of a second screw rod. The other end of the second screw rod sequentially passes through the flange and the crucible table and is connected to the center of a baffle.

[0015] In one embodiment, the distance between the baffle and the top of the crucible table is 6 - 10 mm, and evaporation holes for evaporation are provided on the baffle.

[0016] In one embodiment, the crucibles are all fixed in crucible holes through a plurality of fixing pieces at the top of the crucible table, and the crucible table is provided with air vents.

[0017] In one embodiment, a heat insulation groove is provided between every two adjacent crucibles, and the height of the heat insulation groove is greater than or equal to the height of the crucible hole.

[0018] Compared with the prior art, the advantages of the present invention are that by providing a detachable water-cooled tube, the flange, the crucible table and the water-cooled tube can be separated, so as to directly replace water-cooled tubes of different lengths when using different evaporation distances, avoiding cumbersome disassembly and installation, and thus increasing the usage scenarios of the evaporation source. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Hereinafter, the present invention will be described in more detail based on embodiments and with reference to the drawings.

[0020] Figure 1 is a schematic diagram of the overall structure of the evaporation source of the present invention;

[0021] Figure 2 is a schematic diagram of a partial structure of the crucible table of the present invention;

[0022] Figure 3 is an exploded view of the crucible of the present invention;

[0023] Figure 4 is a connection schematic diagram of the water-cooled tube of the present invention;

[0024] Figure 5 is a schematic diagram of the temperature data of each crucible of the present invention;

[0025] Figure 6 is a schematic diagram when the present invention cools down from 400 °C;

[0026] Reference numerals:

[0027] 1. Crucible table; 2. Side cover; 3. Connector; 4. Water-cooling tube; 5. Baffle; 6. Second screw; 7. Water outlet pipe; 8. Flange; 9. Electrode; 10. Second thermocouple; 11. Rotary introducer; 12. First screw; 13. Fixed piece; 14. Crucible; 15. Heating tube; 16. Base; 17. First thermocouple; 18. Filament; 19. Water inlet pipe; 20. Air vent; 21. Heat insulation groove. Detailed implementation manners

[0028] The present invention will be further described below with reference to the accompanying drawings.

[0029] Please refer to Figures 1 to 6 , the present invention provides a multi-crucible evaporation source, including a crucible table 1, a first screw 12, a water-cooling assembly and a flange 8. Among them, the water-cooling assembly includes a water-cooling tube 4. The water-cooling tube 4 passes through the flange 8 and extends into the crucible table 1 from a reserved hole at the bottom of the crucible table 1. The water-cooling tube 4 is a double-layer sleeve water-cooling tube; the crucible table 1 is used to install a plurality of crucibles 14. In this embodiment, there are three crucibles 14. One side of the crucible table 1 is provided with an openable side cover 2. The bottom of the crucible table 1 and the side cover 2 are provided with reserved holes for installing the water-cooling tube 4. The water-cooling tube 4 is arranged inside the crucible table 1 close to the side cover 2, so that the water-cooling tube 4 can be detachably installed into the inside of the crucible table 1 through the openable side cover 2. A notch is provided on one side of the reserved hole close to the side cover 2. The notch is used to take out the water-cooling tube 4 from the reserved hole. After the water-cooling tube 4 passes through the notch and the side cover 2, it can be separated from the crucible table 1. After the water-cooling tube 4 is installed in the crucible table 1, it can be further fixed by a fixing member to prevent the water-cooling tube 4 from moving and affecting the operation of the evaporation source. When disassembling and replacing the water-cooling tube 4, it does not affect the connection and installation of the crucibles 14 inside the crucible table 1. The crucible table 1 and the side cover 2 are integrally made of oxygen-free copper material treated by gold plating. The oxygen-free copper material has higher thermal conductivity than stainless steel material. The water-cooling tube 4 is arranged inside the crucible table 1, so that the water-cooling tube 4 can quickly cool down and heat up the crucible table 1. As Figure 6 shown, the crucible 14 can be quickly cooled from 400 °C to 50 °C; the crucible table 1 and the flange 8 are detachably connected by a first screw 12; the water-cooling tube 4 and the crucible table 1, the flange 8 are detachably connected. In this embodiment, the first screw 12, the water-cooling tube 4 and the crucible table 1, the flange 8 are all installed and connected by bolt assemblies. The length of the evaporation source in the vacuum can be adjusted by replacing and adjusting the lengths of the water-cooling tube 4 and the first screw 12 according to the actual use situation.

[0030] The crucible table 1 can be a cylinder, a cube or a prism, as long as it can meet the operation of the evaporation source. In this embodiment, a cylinder is preferably used. A plurality of crucibles 14 are placed on one side of the crucible table 1, and the water-cooling pipe 4 is placed on the side of the crucible table 1 close to the side cover 2, which facilitates the disassembly of the water-cooling pipe 4.

[0031] In this embodiment, in order to ensure the collimation of the entire main body part of the evaporation source, a vacuum wire insert can also be embedded at the bottom of the crucible table 1, and a through hole is welded on the flange 8, and the flange 8 and the crucible table 1 can be fixed by the first screw 12.

[0032] For better implementation of the present invention, refer to Figure 3 , in one embodiment, heating pipes 15 are sleeved on the outer peripheries of a plurality of crucibles 14, and a base 16 is provided at the bottoms of the crucibles 14 and the heating pipes 15. The crucibles 14, the heating pipes 15 and the base 16 are together placed into corresponding crucible holes on the crucible table 1.

[0033] The heating pipe 15 adopts an MCH ceramic heating pipe, that is, a cermet heating element. The MCH ceramic heating pipe has the characteristics of fast thermal response speed, and enables the heat to be evenly distributed on the surface of the heating pipe 15. When heating organic materials, the materials can be heated more evenly. In addition, the MCH ceramic heating pipe has the characteristic of linear resistance-temperature change, and more precise temperature regulation can be achieved by precisely controlling the resistance or voltage, which can better meet the strict requirements of organic materials for evaporation temperature. The base 16 at the bottoms of the crucibles 14 and the heating pipes 15 adopts an MCH base that can cooperate with the MCH ceramic heating pipe.

[0034] Each crucible 14 has an independent heating pipe 15, and the stability of each crucible 14 can be precisely controlled respectively, so as to realize the independent evaporation control of different organic materials. The crucibles 14 are made of high-purity quartz with high temperature resistance, good chemical stability and good compatibility with organic materials, so as to ensure that no chemical reaction occurs with organic materials during the high-temperature evaporation process and ensure the purity of the evaporation materials.

[0035] For better implementation of the present invention, refer to Figure 2 , in one embodiment, a first thermocouple 17 is passed through the center of the base 16. After passing through the small hole at the bottom of the crucible table 1, one end of the first thermocouple 17 is connected to one end of a second thermocouple 10 installed on the flange 8, and the other end of the second thermocouple 10 is connected to a control system for temperature monitoring.

[0036] The outer periphery of the first thermocouple 17 is sleeved with a ceramic tube for insulation treatment.

[0037] The control system can adopt the PID algorithm and thermocouple sensors, which can respond quickly and accurately to temperature changes, stably control the temperature of crucible 14 within ±0.1 °C of the set value, and has temperature monitoring and alarm functions. When the temperature exceeds the normal working range, it will issue an alarm in time and take corresponding protection measures to prevent abnormal situations such as overheating damage of crucible 14 and decomposition and carbonization of organic materials.

[0038] To better implement this invention, refer to Figure 2 , in one embodiment, the lead of heating tube 15 passes through the bottom of crucible table 1 and is connected to one end of filament 18 through connector 3. The other end of filament 18 is connected to one end of electrode 9. Electrode 9 is installed on flange 8, and the other end of electrode 9 is connected to the control system. A Teflon tube is sleeved outside filament 18 for insulation treatment.

[0039] To better implement this invention, refer to Figure 1 , in one embodiment, a rotary introducer 11 is also provided on flange 8. Rotary introducer 11 is connected to one end of second screw 6. The other end of second screw 6 sequentially passes through flange 8 and crucible table 1 and is connected to the center of baffle 5. The distance between baffle 5 and the top of crucible table 1 is 6 - 10 mm. In this embodiment, it is preferably 8 cm between the top of crucible table 1 and baffle 5. Baffle 5 can be clamped by two nuts sleeved on second screw 6 to limit the position of baffle 5. When adjusting the length of the evaporation source in the vacuum part, that is, the length of water-cooled tube 4, it is necessary to further adjust the position of the two nuts to adjust the position of baffle 5 to ensure that the distance between baffle 5 and the top of crucible table 1 is within 6 - 10 mm. There are evaporation holes for evaporation on baffle 5. The distance from the center of the evaporation holes to second screw 6 is the same as the distance from the center of crucible 14 to second screw 6. Rotating rotary introducer 11 can drive second screw 6 to rotate. Second screw 6 will drive baffle 5 to rotate together. By adjusting the correspondence between the evaporation holes on baffle 5 and crucible 14, different crucibles 14 can be controlled to work.

[0040] Rotary introducer 11 and second screw 6 can be connected by threads. Rotary introducer 11 can also control the rotation of second screw 6 in a magnetic coupling manner.

[0041] To better implement this invention, refer to Figure 2, in one embodiment, the crucible 14 is fixed in the crucible hole through a plurality of fixing pieces 13 at the top of the crucible table 1. To ensure the stability of the crucible 14, at least two fixing pieces 13 are provided for each crucible 14, and three fixing pieces 13 are preferably provided in this embodiment. When the crucible 14 needs to be disassembled, only need to rotate the fixing piece 13 and move the fixing piece 13 away from above the crucible hole, then the crucible 14 can be taken out from the crucible hole. Similarly, when the crucible 14 needs to be fixed, after the crucible 14 is placed in the crucible hole, rotate the fixing piece 13 to block the crucible 14 to prevent the crucible 14 from falling out of the crucible hole.

[0042] To better implement the present invention, refer to Figure 2 , in one embodiment, an insulating groove 21 is provided between every two adjacent crucibles 14, and the height of the insulating groove 21 is greater than or equal to the height of the crucible hole, the length is greater than or equal to the diameter of the crucible hole, and the width of the insulating groove 21 is 1-3 mm. In this embodiment, an insulating groove with a width of 2 mm is preferably used. The insulating groove 21 is used to prevent the crucibles 14 from affecting each other during operation, such as Figure 5 shown, the temperatures of the three crucibles 14 in the evaporation source described in this embodiment do not affect each other when operating in the heating or constant temperature mode. The crucible table 1 is also provided with an air vent 20.

[0043] To better implement the present invention, refer to Figure 4 , in one embodiment, the water cooling assembly further includes a water inlet pipe 19 and a water outlet pipe 7 installed on the flange 8. Both ends of the water cooling pipe 4 pass through the flange 8 and are detachably connected to the water inlet pipe 19 and the water outlet pipe 7 respectively. The water inlet pipe 19, the water outlet pipe 7 and the water cooling pipe 4 can also be set as a whole and directly installed on the flange 8. When the water cooling pipe 4 needs to be replaced, the water inlet pipe 19, the water outlet pipe 7 and the water cooling pipe 4 are removed as a whole.

[0044] Based on the above multi-crucible evaporation source, its working principle is:

[0045] The operator drives the second screw rod 6 and the baffle 5 to rotate by rotating the rotary introducer 11, so as to control the evaporation holes on the baffle 5 to align with the crucible 14 in operation. When the crucible 14 is heated, water enters through the water inlet pipe 19, and the cooling water enters the water-cooling pipe 4 to cool the entire crucible table 1 and flows out from the water outlet pipe 7. When different evaporation distances are required, the first screw rod 12 is removed and replaced with a first screw rod 12 of the required length. Then, the side cover 2 of the crucible table 1 is opened, and the water-cooling pipe 4 is taken out together and replaced with a water-cooling pipe 4 of the appropriate length. The side cover 2 is closed, and the corresponding bolt assemblies are tightened. Similarly, since the distance between the crucible table 1 and the flange 8 changes, the position of the baffle 5 on the second screw rod 6 also needs to be adjusted so that the distance between the baffle 5 and the top of the crucible table 1 is maintained at 6-10 mm, or a second screw rod 6 of the appropriate length is replaced to ensure that the distance between the baffle 5 and the top of the crucible table 1 is maintained at 6-10 mm. Compared with the conventional evaporation source, in this embodiment, the main part is modularly designed. When different evaporation distances are satisfied, it is not necessary to disassemble the filament 18, the thermocouple, etc. together. Only the water-cooling pipe 4, the first screw rod 12 and the second screw rod 6 of different lengths need to be replaced, which greatly reduces the disassembly workload of the evaporation source and simplifies the cumbersome process of disassembly and installation during the use of the evaporation source.

[0046] Although the present invention has been described with reference to the preferred embodiments, various modifications can be made to it and components therein can be replaced with equivalents without departing from the scope of the present invention. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present invention is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A multi-crucible evaporation source, characterized in that: It includes a crucible table, a first screw, a water cooling assembly and a flange, wherein: The water cooling assembly includes a water cooling pipe, which passes through the flange and extends into the crucible table from a reserved hole at the bottom of the crucible table; The crucible table is used to install a plurality of the crucibles, and an openable side cover is provided on one side of the crucible table, so that the water cooling tube can be detachably installed into the interior of the crucible table through the openable side cover; The crucible table and the flange are detachably connected via the first screw; The water cooling tube, the crucible table and the flange are detachably connected.

2. The multi-crucible evaporation source according to claim 1, characterized in that: A notch is provided on one side of the reserved hole close to the side cover, and the notch is used to take the water cooling pipe out of the reserved hole. The water cooling pipe can be separated from the crucible table after passing through the notch and the side cover.

3. The multi-crucible evaporation source according to claim 2, characterized in that: The water cooling assembly also includes a water inlet pipe and a water outlet pipe installed on the flange. Both ends of the water cooling pipe pass through the flange and are detachably connected to the water inlet pipe and the water outlet pipe respectively.

4. The multi-crucible evaporation source according to claim 1, characterized in that: The outer circumferences of the plurality of crucibles are all sleeved with heating tubes, the bottoms of the crucibles and the heating tubes are provided with bases, and the crucibles, the heating tubes and the bases are placed together in corresponding crucible holes on the crucible table.

5. The multi-crucible evaporation source according to claim 1 or 4, characterized in that: A first thermocouple is arranged at the center of the base. The first thermocouple passes through a small hole at the bottom of the crucible table and is connected to one end of a second thermocouple installed on the flange. The other end of the second thermocouple is connected to a control system for temperature monitoring.

6. The multi-crucible evaporation source according to claim 5, characterized in that: The lead wire of the heating tube passes through the bottom of the crucible table and is connected to one end of the filament. The other end of the filament is connected to one end of the electrode. The electrode is mounted on the flange. The other end of the electrode is connected to the control system.

7. The multi-crucible evaporation source according to claim 1, characterized in that: The flange is also provided with a rotary introducer, which is connected to one end of the second screw, and the other end of the second screw sequentially penetrates the flange and the crucible table and is connected to the center of the baffle.

8. The multi-crucible evaporation source according to claim 7, characterized in that: The distance between the baffle and the top of the crucible table is 6-10 mm, and the baffle is provided with evaporation holes for evaporation.

9. The multi-crucible evaporation source according to claim 4 or 8, characterized in that: The crucibles are all fixed in the crucible holes through a plurality of fixing plates on the top of the crucible platform, and the crucible platform is provided with a venting hole.

10. The multi-crucible evaporation source according to claim 4, characterized in that: An insulation groove is provided between every two adjacent crucibles, and the height of the insulation groove is greater than or equal to the height of the crucible hole.

Images