Binding method of rotating molybdenum target material

Abstract

The invention relates to the technical field of sputtering target material binding, in particular to a binding method of a rotating molybdenum target material. The binding method of the rotating molybdenum target material comprises the following steps of back pipe treatment, rotating molybdenum target treatment, rotating target material installation, rotating target material assembly and rotating target material binding. According to the method, the back tube and the rotating molybdenum target are subjected to roughening treatment twice and ultra-indium alternate treatment twice, so that alloy impurities are reduced, the bonding strength between the target and the backing tube is improved, the binding rate and the overall reliability of the target are improved, and the service life of the target is prolonged while it is guaranteed that the target and the back tube have good adhesion performance. And the binding rate of the target material is up to 98% or above.

Description

Technical Field

[0001] The invention relates to the technical field of sputtering target binding, and in particular to a method for binding a rotating molybdenum target. Background Art

[0002] Sputtering technology refers to the technology of bombarding the solid surface with particles with a certain energy to make the atoms or molecules on the solid surface leave the solid surface and sputter out. The solid is usually called a target material. The sputtered atoms or molecules fall on another solid surface to form a coating. The coated solid is usually called a substrate. Sputtering coating has now become one of the most important technologies in industrial coating production. Ceramic targets such as zinc telluride, cadmium telluride, cadmium zinc telluride and other sputtering targets are used as raw materials for magnetron sputtering coating. Their quality has a great influence on the performance of the film layer, and also affects the production efficiency, cost and quality of the coating. With the rapid development of the electronic information industry, the size of chips continues to decrease, the integration of electronic devices in integrated circuits continues to increase, and the uniformity requirements for target sputtering coating are also getting higher and higher.

[0003] The rotating targets used in the sputtering coating industry are usually bound with stainless steel back tubes or titanium back tubes. The commonly used binding materials are metal indium or other metal substances. Target material binding is a target material deep processing technology, that is, the target material and the back tube are bonded together using materials with good adhesion and ductility, and the formed bonding layer has certain electrical conductivity, thermal conductivity and bonding strength. Before binding, it is necessary to consider the adhesion of the solder and the target material.

[0004] The patent technical document CN202011149681.X discloses a method for binding a target material. The invention controls the cooling rate of the rotating target material and the back tube to room temperature at a rate of 0.5-2.5℃ / min after indium injection, and fills the indium from bottom to top. The air in the weld space can be fully discharged, so that the cooled target material and the back tube are tightly combined, which can effectively avoid the appearance of bubbles in the filling indium liquid, significantly increase the binding rate of the target material, and improve the technical problems of target cracking and nodule formation. However, due to the large difference in thermal stress of the materials, the adhesion between the target material and the back tube is poor, which leads to a low binding rate of the target material, and the binding quality needs to be further improved. Summary of the invention

[0005] In view of this, the purpose of the present invention is to propose a method for binding a rotating molybdenum target material, so as to provide a method for binding a rotating molybdenum target material, so that the adhesion between the target material and the back tube after binding is strong and the binding effect is good.

[0006] Based on the above purpose, the present invention provides a method for binding a rotating molybdenum target, comprising the following steps:

[0007] S1: performing a first roughening treatment on the rotating molybdenum target and the back tube respectively, and then preheating the rotating molybdenum target and the back tube to 175-185° C., performing a first ultrasonic indium coating treatment, and cooling to obtain a pretreated rotating molybdenum target and back tube;

[0008] S2: The pretreated rotating molybdenum target and back tube are subjected to a second roughening treatment respectively, and then preheated to 175-185°C, subjected to a second ultrasonic indium coating treatment, and kept warm;

[0009] S3: installing the back tube in step S2 in the rotating molybdenum target, inserting four aluminum wires into the gap between the rotating target and the back tube for fixing, so that a welding seam space is formed between the rotating molybdenum target and the back tube;

[0010] S4: After the rotating target material in step S3 is cooled to room temperature, the bottom of the rotating target material is sealed, and an indium groove is established on the rotating top;

[0011] S5: Heat the rotating target assembled in step S4 to 185-215° C., connect an air pump, and pour indium liquid into the weld space. Stop pouring when the indium liquid level is about 2 cm from the top of the back tube end face, and cool to room temperature.

[0012] Furthermore, after the first roughening treatment in step S1, the roughness of the back tube to be welded surface and the rotating molybdenum target to be welded surface are both 4μm-10μm; the thickness of the first ultrasonic indium coating is 0.02-0.03mm.

[0013] Furthermore, after the second roughening treatment in step S2, the roughness of the back tube to be welded surface and the rotating molybdenum target to be welded surface are both 4μm-10μm; the thickness of the second ultrasonic indium coating is 0.02-0.03mm.

[0014] Furthermore, the sizes of the four aluminum wires in step S3 are all L6-8 mm*Ф1 mm, and the insertion directions are 0°, 90°, 180°, and 270° respectively.

[0015] Furthermore, the air pressure of the air pump in step S5 is 0.2-0.4Mpa.

[0016] Furthermore, in step S5, the pouring is stopped when the indium liquid level is about 2 cm away from the top of the back tube end surface. After 5-6 minutes, the indium liquid level is observed. If the indium level drops, indium is added in time.

[0017] Furthermore, the back tube is a stainless steel back tube.

[0018] Furthermore, the temperature of the indium liquid is 190-200°C.

[0019] Furthermore, the roughening treatment is performed using a sandblasting machine, and the process parameters of the roughening treatment are: the distance between the spray gun and the back tube is 8cm-15cm, the air pressure of the sandblasting machine is 0.2MPa-0.6MPa, and the movement speed of the spray gun is 200mm / min-500mm / min.

[0020] Furthermore, the roughening treatment uses white corundum sand or brown corundum sand with a particle size of 20-40 meshes.

[0021] Beneficial effects of the present invention:

[0022] The present invention adopts two roughening treatments and two super indium treatments, and performs them alternately. On the one hand, it realizes a deeper mechanical bite and improves the bonding strength between the target material and the backing tube; and can further reduce gaps and pores, thereby increasing the density of the indium layer and reducing thermal stress; on the other hand, it makes the indium layer more evenly distributed, reduces the generation of alloy impurities and thus improves the efficiency of heat conduction, reduces the thermal stress between the substrates, maintains a better bonding state, and thus improves the binding rate of the target material and the overall reliability. DETAILED DESCRIPTION

[0023] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0024] Embodiment 1: A method for binding a rotating molybdenum target, the specific steps are as follows:

[0025] (1) Back tube treatment: The stainless steel back tube surface to be welded is subjected to the first roughening treatment, and then it is preheated to 175°C, and the first ultrasonic indium coating treatment is performed, and the thickness of the indium layer is 0.02 mm. After cooling, the second roughening treatment is performed, and then it is preheated to 175°C, and the second ultrasonic indium coating treatment is performed, and the thickness of the indium layer is 0.02 mm, and the heat is kept; wherein, white corundum sand with a particle size of 20 mesh is used for sandblasting, and the process parameters are: the distance between the spray gun and the back tube is 15 cm, the air pressure of the sandblasting machine is 00.6 MPa, and the movement speed of the spray gun is 500 mm / min;

[0026] (2) Rotating molybdenum target treatment: The rotating molybdenum target surface to be welded is subjected to the first roughening treatment, and then preheated to 175°C, subjected to the first ultrasonic indium coating treatment, and the thickness of the indium layer is 0.02 mm. After cooling, the second roughening treatment is performed, and then preheated to 175°C, subjected to the second ultrasonic indium coating treatment, and the thickness of the indium layer is 0.02 mm, and kept warm; wherein, white corundum sand with a particle size of 20 mesh is used for sandblasting, and the process parameters are: the distance between the spray gun and the back tube is 15 cm, the air pressure of the sandblasting machine is -0.6 MPa, and the movement speed of the spray gun is 500 mm / min;

[0027] (3) Installation of rotating target: Install the above-mentioned stainless steel back tube in the rotating molybdenum target, insert four aluminum wires (L6 mm*Ф1 mm) into the gap between the rotating target and the back tube to fix it. Both ends of the rotating target should be inserted to form a welding space between the rotating molybdenum target and the back tube. Cut off the excess aluminum wires, and then turn off the power to cool down.

[0028] (4) Rotating target assembly: After the rotating target in step (3) is cooled to room temperature, an O-ring is used to seal the bottom of the rotating target, and an indium groove is established at the rotating top;

[0029] (5) Rotating target binding: Heat the assembled rotating target to 185°C, then connect the vibration air pump, adjust the air pressure to 0.2Mpa, and then pour 190°C indium liquid into the weld space. Stop pouring when the indium liquid level is about 2cm from the top of the back tube end face. After 5 minutes, observe the indium liquid level. If the indium level drops, add indium in time. If not, cool directly to room temperature.

[0030] Embodiment 2: A method for binding a rotating molybdenum target, the specific steps are as follows:

[0031] (1) Back tube treatment: The stainless steel back tube surface to be welded is subjected to the first roughening treatment, and then it is preheated to 180°C, and the first ultrasonic indium coating treatment is performed, and the thickness of the indium layer is 0.03 mm. After cooling, the second roughening treatment is performed, and then it is preheated to 180°C, and the second ultrasonic indium coating treatment is performed, and the thickness of the indium layer is 0.03 mm, and the heat is kept; wherein, white corundum sand with a particle size of 30 mesh is used for sandblasting, and the process parameters are: the distance between the spray gun and the back tube is 10 cm, the air pressure of the sandblasting machine is 0.4 MPa, and the movement speed of the spray gun is 300 mm / min;

[0032] (2) Rotating molybdenum target treatment: The rotating molybdenum target surface to be welded is subjected to the first roughening treatment, and then it is preheated to 180°C, and the first ultrasonic indium coating treatment is carried out, and the thickness of the indium layer is 0.03 mm. After cooling, the second roughening treatment is carried out, and then it is preheated to 180°C, and the second ultrasonic indium coating treatment is carried out, and the thickness of the indium layer is 0.03 mm, and the heat is kept; wherein, white corundum sand with a particle size of 30 mesh is used for sandblasting, and the process parameters are: the distance between the spray gun and the back tube is 12 cm, the air pressure of the sandblasting machine is 0.4 MPa, and the movement speed of the spray gun is 300 mm / min;

[0033] (3) Installation of rotating target: Install the above-mentioned stainless steel back tube in the rotating molybdenum target, insert four aluminum wires (L7 mm*Ф1 mm) into the gap between the rotating target and the back tube to fix it. Both ends of the rotating target should be inserted to form a welding space between the rotating molybdenum target and the back tube, cut off the excess aluminum wire, and then turn off the power to cool down;

[0034] (4) Rotating target assembly: After the rotating target in step (3) is cooled to room temperature, an O-ring is used to seal the bottom of the rotating target, and an indium groove is established at the rotating top;

[0035] (5) Rotating target binding: Heat the assembled rotating target to 205°C, then connect the vibration air pump, adjust the air pressure to 0.3Mpa, and then pour 195°C indium liquid into the weld space. Stop pouring when the indium liquid level is about 2 cm from the top of the back tube end face. After 5 minutes, observe the indium liquid level. If the indium level drops, add indium in time. If not, cool directly to room temperature.

[0036] Embodiment 3: A method for binding a rotating molybdenum target, the specific steps are as follows:

[0037] (1) Back tube treatment: The stainless steel back tube surface to be welded is subjected to the first roughening treatment, and then it is preheated to 185°C, and the first ultrasonic indium coating treatment is performed, and the thickness of the indium layer is 0.03 mm. After cooling, the second roughening treatment is performed, and then it is preheated to 185°C, and the second ultrasonic indium coating treatment is performed, and the thickness of the indium layer is 0.03 mm, and the heat is kept; wherein, white corundum sand with a particle size of 40 mesh is used for sandblasting, and the process parameters are: the distance between the spray gun and the back tube is 8 cm, the air pressure of the sandblasting machine is 0.2 MPa, and the movement speed of the spray gun is 200 mm / min;

[0038] (2) Rotating molybdenum target treatment: The rotating molybdenum target surface to be welded is subjected to the first roughening treatment, and then it is preheated to 185°C, and the first ultrasonic indium coating treatment is carried out, and the thickness of the indium layer is 0.03 mm. After cooling, the second roughening treatment is carried out, and then it is preheated to 185°C, and the second ultrasonic indium coating treatment is carried out, and the thickness of the indium layer is 0.03 mm, and the heat is kept; wherein, white corundum sand with a particle size of 40 mesh is used for sandblasting, and the process parameters are: the distance between the spray gun and the back tube is 8 cm, the air pressure of the sandblasting machine is 0.2 MPa, and the movement speed of the spray gun is 200 mm / min;

[0039] (3) Installation of rotating target: Install the above-mentioned stainless steel back tube in the rotating molybdenum target, insert four aluminum wires (L8 mm*Ф1 mm) into the gap between the rotating target and the back tube to fix it. Both ends of the rotating target should be inserted to form a welding space between the rotating molybdenum target and the back tube. Cut off the excess aluminum wires, and then turn off the power to cool down.

[0040] (4) Rotating target assembly: After the rotating target in step (3) is cooled to room temperature, an O-ring is used to seal the bottom of the rotating target, and an indium groove is established at the rotating top;

[0041] (5) Rotating target binding: Heat the assembled rotating target to 215°C, then connect the vibration air pump, adjust the air pressure to 0.4 MPa, and then pour 200°C indium liquid into the weld space. Stop pouring when the indium liquid level is about 2 cm from the top of the back tube end face. After 6 minutes, observe the indium liquid level. If the indium level drops, add indium in time. If not, cool directly to room temperature.

[0042] Comparative Example 1: A method for binding a target material, the specific steps are as follows:

[0043] The difference from Example 2 is that the back tube and the rotating molybdenum target are not subjected to the second roughening treatment, and the remaining steps are the same as Example 2, which will not be described in detail here.

[0044] Comparative Example 2: A method for binding a target material, the specific steps are as follows:

[0045] The difference from Example 2 is that the back tube and the rotating molybdenum target are not subjected to a second indium coating treatment, and the remaining steps are the same as those of Example 2, which will not be described in detail here.

[0046] Comparative Example 3: A method for binding a target material, the specific steps are as follows:

[0047] The difference from Example 2 is that the back tube and the rotating molybdenum target are not subjected to the second roughening treatment and the second indium coating treatment. The remaining steps are the same as those in Example 2 and are not described in detail here.

[0048] Performance Testing

[0049] Tensile stress of target material and back tube: According to GB / T11363-2008, the samples obtained in the embodiment and the comparative example were tested, and the test results are shown in Table 1.

[0050] Table 1 Performance test results

[0051] Binding rate (%) <![CDATA[Tensile stress (kg / cm 3 )]]> Example 1 98.7 32.4 Example 2 99.5 30.8 Example 3 98.3 29.4 Comparative Example 1 96.7 23.5 Comparative Example 2 97.4 26.8 Comparative Example 3 95.2 20.5

[0052] Data analysis: It can be seen from Table 1 Implementation 1-3 that the binding method of the rotating molybdenum target material of the present invention can make the target material and the solder have excellent adhesion and binding performance, and the binding rate can reach more than 98%, which can effectively avoid the alloy impurities generated by the target material during the binding process. The binding rate after being processed by the binding method of the present invention is high and the production efficiency is high.

[0053] It can be seen from Example 2 and Comparative Examples 1, 2 and 3 in Table 1 that the present invention achieves deeper mechanical bite and improves the bonding strength between the target material and the backing tube by using two roughening treatments and two super indium alternating treatments on the backing tube and the rotating molybdenum target; and can further reduce voids and pores, thereby increasing the density of the indium layer and reducing thermal stress; on the other hand, it makes the distribution points of the indium layer more uniform, reduces the generation of alloy impurities and thus improves the efficiency of heat conduction, reduces the thermal stress between the substrates, maintains a better bonding state, and thus improves the binding rate and overall reliability of the target material.

[0054] The present invention is intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for binding a rotating molybdenum target. It is characterized in that The following steps are involved: S1: performing a first roughening treatment on the rotating molybdenum target and the back tube respectively, and then preheating the rotating molybdenum target and the back tube to 175-185° C., performing a first ultrasonic indium coating treatment, and cooling to obtain a pretreated rotating molybdenum target and back tube; S2: The pretreated rotating molybdenum target and back tube are subjected to a second roughening treatment respectively, and then preheated to 175-185° C., subjected to a second ultrasonic indium coating treatment, and kept warm; S3: installing the back tube in step S2 in the rotating molybdenum target, inserting four aluminum wires into the gap between the rotating target and the back tube for fixing, so that a welding seam space is formed between the rotating molybdenum target and the back tube; S4: After the rotating target material in step S3 is cooled to room temperature, the bottom of the rotating target material is sealed, and an indium groove is established on the rotating top; S5: Heat the rotating target assembled in step S4 to 185-215° C., connect an air pump, and pour indium liquid into the weld space. Stop pouring when the indium liquid level is about 2 cm from the top of the back tube end face, and cool to room temperature.

2. The method for binding a rotating molybdenum target according to claim 1, It is characterized in that After the first roughening treatment in step S1, the roughness of the back tube to be welded surface and the rotating molybdenum target to be welded surface are both 4μm-10μm; the thickness of the first ultrasonic indium coating is 0.02-0.03mm.

3. The method for binding a rotating molybdenum target according to claim 1, It is characterized in that After the second roughening treatment in step S2, the roughness of the back tube to be welded surface and the rotating molybdenum target to be welded surface are both 4μm-10μm; the thickness of the second ultrasonic indium coating is 0.02-0.03mm.

4. The method for binding a rotating molybdenum target according to claim 1, It is characterized in that The sizes of the four aluminum wires in step S3 are all L6-8 mm*Ф1 mm, and the insertion directions are 0°, 90°, 180°, and 270° respectively.

5. The method for binding a rotating molybdenum target according to claim 1, It is characterized in that The air pressure of the air pump in step S5 is 0.2-0.4Mpa.

6. The method for binding a rotating molybdenum target according to claim 1, It is characterized in that In step S5, the pouring is stopped when the indium liquid level is about 2 cm away from the top of the back tube end surface. After 5-6 minutes, the indium liquid level is observed. If the indium level drops, indium is added in time.

7. The method for binding a rotating molybdenum target according to claim 1, It is characterized in that The back tube is a stainless steel back tube.

8. The method for binding a rotating molybdenum target according to claim 1, It is characterized in that The roughening treatment is performed by a sandblasting machine, and the process parameters of the roughening treatment are: the distance between the spray gun and the back tube is 8cm-15cm, the air pressure of the sandblasting machine is 0.2MPa-0.6MPa, and the movement speed of the spray gun is 200mm / min-500mm / min.

9. The method for binding a rotating molybdenum target according to claim 1, It is characterized in that The roughening treatment uses white corundum sand or brown corundum sand with a particle size of 20-40 meshes.