阅读说明：本技术 一种长尺寸的ito旋转靶筒烧结方法 (Sintering method of long-size ITO (indium tin oxide) rotary target cylinder ) 是由 曾探 王志强 盛明亮 曾墩风 马建保 石煜 于 2021-08-02 设计创作，主要内容包括：本发明提供一种长尺寸的ITO旋转靶筒烧结方法,首先通过方形的中间带有贯通圆孔的氧化铝承烧板来放置靶筒,这样气流可以从靶材内壁均匀对流,温度均匀性好；再通过采用两个碳化硅筒上下叠放在一起套在靶筒外,碳化硅筒中部均匀分布四个方孔,下方碳化硅筒放在氧化铝承烧板周围的氧化铝垫块上,这样确保在气氛烧结的过程中,靶筒四周的温度均匀性好,烧结过程中,气流可以从碳化硅筒底部中间均匀对流,并且避免氧气直吹；最后通过烧结曲线烧结,烧结升温时间延长和降温时间延长,使靶筒收缩均匀,能够正常烧结长度750-1000mm的ITO旋转靶筒,且直线度良好不易弯曲,不需要切割,可直接进行机加工。(The invention provides a sintering method of a long ITO rotary target cylinder, which comprises the following steps that firstly, a target cylinder is placed through a square alumina burning bearing plate with a through round hole in the middle, so that air flow can be uniformly convected from the inner wall of a target material, and the temperature uniformity is good; two silicon carbide cylinders are stacked up and down and sleeved outside the target cylinder, four square holes are uniformly distributed in the middle of the silicon carbide cylinders, and the lower silicon carbide cylinder is placed on an alumina cushion block around an alumina burning bearing plate, so that the temperature uniformity around the target cylinder is good in the atmosphere sintering process, airflow can be uniformly convected from the middle of the bottom of the silicon carbide cylinder in the sintering process, and oxygen direct blowing is avoided; and finally, sintering through a sintering curve, prolonging the sintering temperature rise time and the temperature reduction time, so that the target cylinder is uniformly shrunk, the ITO rotary target cylinder with the length of 750-plus-material 1000mm can be normally sintered, the straightness is good, the target cylinder is not easy to bend, cutting is not needed, and machining can be directly carried out.)

1. A sintering method of a long ITO rotary target cylinder is characterized by comprising the following steps: the method comprises the following steps:

the method comprises the following steps: firstly, a square alumina burning plate (2) with a longitudinal through round hole (1) in the middle is placed in an oxygen atmosphere normal pressure sintering furnace;

step two: then placing alumina cushion blocks (3) at intervals around the alumina setter plate (2), wherein the alumina cushion blocks (3) are flush with the alumina setter plate (2) in height;

step three: two ends of a 1000mm target cylinder (4) are ground flat, then the target cylinder (4) is placed on an alumina burning board (2), a round hole (1) of the alumina burning board (2) faces to a through hole of the target cylinder (4), and the round hole of the alumina burning board is smaller than the through hole of the target cylinder;

step four: two silicon carbide cylinders (5) are stacked up and down and sleeved outside the target cylinder (4), four square holes (6) are uniformly formed in the middle of each silicon carbide cylinder (5), the silicon carbide cylinder (5) positioned below is placed on the alumina cushion block (3), and the silicon carbide cylinders (5) and the target cylinder (4) are equal in interval from top to bottom;

step five: sintering is carried out in an oxygen atmosphere normal pressure sintering furnace by adopting a sintering curve.

2. The sintering method of the long-sized ITO rotary target cylinder as claimed in claim 1, wherein: the diameter of the round hole of the alumina setter plate (2) is 30-50 mm.

3. The sintering method of the long-sized ITO rotary target cylinder as claimed in claim 1, wherein: the side length of the square hole (6) of the silicon carbide cylinder (5) is 15-20mm, and the height of the two silicon carbide cylinders (5) which are overlapped together is equal to the height of the target cylinder (4).

4. The sintering method of the long-sized ITO rotary target cylinder as claimed in claim 1, wherein: the four square holes (6) of the silicon carbide cylinder (5) are arranged around the middle part of the silicon carbide cylinder in a cross shape.

5. The sintering method of the long-sized ITO rotary target cylinder as claimed in claim 1, wherein: the step five sintering curve is as follows: the furnace temperature of the oxygen atmosphere normal pressure sintering furnace is firstly preheated to 600 ℃, then the temperature is raised from 600 ℃ to 1100-1400 ℃, then the temperature is preserved, then the temperature is raised to 1500-1600 ℃, then the temperature is preserved, finally the temperature is lowered to the room temperature, and the sintering is finished.

6. The sintering method of the long-sized ITO rotary target cylinder as claimed in claim 5, wherein: the temperature rise time from 600 ℃ to 1100-1400 ℃ is 10-20 h; the heat preservation time is 5-10h at 1100-1400 ℃; the temperature rise time from 1100-1400 ℃ to 1500-1600 ℃ is 15-20 h; the heat preservation time of 1500-1600 ℃ is 30-40 h.

Technical Field

The invention relates to the field of ITO target materials, in particular to a sintering method of a long-size ITO rotary target cylinder.

Background

The ITO target belongs to indium tin composite oxide ceramic, is an important photoelectric functional material, is often used as a magnetron sputtering target to prepare transparent conductive films on substrate materials such as glass, plastic and the like, and is used for producing flat panel display equipment such as a liquid crystal display, a touch screen and the like. At present, there are two kinds of ITO targets, one is a planar indium tin oxide target, and the other is a rotary indium tin oxide target. The rotary indium tin oxide target material has the characteristic of high utilization rate in the magnetron sputtering process and is widely used.

The ITO target material is rotated, and the ITO target cylinder needs to be sintered in the preparation process. The length of the ITO rotary target cylinder is generally divided into 3 stages: 200-. At present, the sintering process is generally stopped at the target sintering stage with the length of 200-. While a rotating target cylinder with the sintering length of 750 and 1000mm is more difficult to add. The ITO rotary target cylinder is sintered, and the longer the length is, the more difficult the sintering preparation is. Severe bending generally occurs and yields are very poor. The prior art patent CN 111023838A discloses a sintering method of a tubular rotary ceramic target, which promotes the full sintering of the target by placing a tubular rotary ceramic target green body on a sliding part with a sliding surface for sintering, wherein the inclination angle of the sliding surface relative to the horizontal plane is 10-50 degrees, which can greatly reduce the friction force between the target green body and a sintering bearing plate caused by shrinkage during sintering. However, in the production process, the silicon-molybdenum rod of the heating element of the sintering furnace is closer to the target cylinder, so that the heating and air intake of the product are uneven, the target cylinder is easy to bend, and the sintering furnace is not suitable for sintering the existing long target cylinder, so that the problem is very necessary to be solved.

Disclosure of Invention

In order to solve the problems, the invention provides a sintering method of a long ITO rotary target cylinder, which comprises the following steps of firstly placing the target cylinder through a square alumina burning bearing plate with a through round hole in the middle, so that air flow can be uniformly convected from the inner wall of the target material, and the temperature uniformity is good; two silicon carbide cylinders are stacked up and down and sleeved outside the target cylinder, four square holes are uniformly distributed in the middle of the silicon carbide cylinders, and the lower silicon carbide cylinder is placed on an alumina cushion block around an alumina burning bearing plate, so that the temperature uniformity around the target cylinder is good in the atmosphere sintering process, airflow can be uniformly convected from the middle of the bottom of the silicon carbide cylinder in the sintering process, and oxygen direct blowing is avoided; and finally, sintering is carried out through a sintering curve, the sintering temperature rise time is prolonged, the temperature reduction time is prolonged, so that the target cylinder is uniformly shrunk, the ITO rotary target cylinder with the length of 750-plus-material 1000mm can be normally sintered, the straightness is good, the ITO rotary target cylinder is not easy to bend, cutting is not needed, machining can be directly carried out, and the problem of high difficulty in long-time rotary sintering is solved.

The invention aims to provide a sintering method of a long ITO rotary target cylinder, which comprises the following steps:

the method comprises the following steps: firstly, placing a square alumina burning bearing plate with a longitudinal through round hole in the middle into an oxygen atmosphere normal pressure sintering furnace;

step two: then placing alumina cushion blocks at intervals around the alumina setter plate, wherein the alumina cushion blocks are flush with the alumina setter plate in height;

step three: grinding two ends of a 1000mm target cylinder, then placing the target cylinder on an alumina burning bearing plate, wherein the round hole of the alumina burning bearing plate faces to the through hole of the target cylinder, and the round hole of the alumina burning bearing plate is smaller than the through hole of the target cylinder;

step four: two silicon carbide cylinders are stacked up and down and sleeved outside the target cylinder, four square holes are uniformly formed in the middle of the silicon carbide cylinder, the silicon carbide cylinder positioned below is placed on an alumina cushion block, and the intervals between the silicon carbide cylinder and the target cylinder are equal from top to bottom;

step five: sintering is carried out in an oxygen atmosphere normal pressure sintering furnace by adopting a sintering curve.

The further improvement lies in that: the diameter of the round hole of the alumina setter plate is 30-50 mm.

The further improvement lies in that: the side length of the square hole of the silicon carbide cylinder is 15-20mm, and the height of the two silicon carbide cylinders which are stacked together is equal to the height of the target cylinder.

The further improvement lies in that: four square holes of the silicon carbide cylinder are arranged around the middle part of the silicon carbide cylinder in a cross shape.

The further improvement lies in that: the step five sintering curve is as follows: the furnace temperature of the oxygen atmosphere normal pressure sintering furnace is firstly preheated to 600 ℃, then the temperature is raised from 600 ℃ to 1100-1400 ℃, then the temperature is preserved, then the temperature is raised to 1500-1600 ℃, then the temperature is preserved, finally the temperature is lowered to the room temperature, and the sintering is finished.

The further improvement lies in that: the temperature rise time from 600 ℃ to 1100-1400 ℃ is 10-20 h; the heat preservation time is 5-10h at 1100-1400 ℃; the temperature rise time from 1100-1400 ℃ to 1500-1600 ℃ is 15-20 h; the heat preservation time of 1500-1600 ℃ is 30-40 h.

The invention has the beneficial effects that: according to the invention, the target cylinder is placed through the square alumina burning bearing plate with the through round hole in the middle, so that air flow can be uniformly convected from the inner wall of the target material, and the temperature uniformity is good; two silicon carbide cylinders are stacked up and down and sleeved outside the target cylinder, four square holes are uniformly distributed in the middle of the silicon carbide cylinders, and the lower silicon carbide cylinder is placed on an alumina cushion block around an alumina burning bearing plate, so that the temperature uniformity around the target cylinder is good in the atmosphere sintering process, airflow can be uniformly convected from the middle of the bottom of the silicon carbide cylinder in the sintering process, and oxygen direct blowing is avoided; and finally, sintering is carried out through a sintering curve, the sintering temperature rise time is prolonged, the temperature reduction time is prolonged, so that the target cylinder is uniformly shrunk, the ITO rotary target cylinder with the length of 750-plus-material 1000mm can be normally sintered, the straightness is good, the ITO rotary target cylinder is not easy to bend, cutting is not needed, machining can be directly carried out, and the problem of high difficulty in long-time rotary sintering is solved.

Drawings

FIG. 1 is a schematic illustration of the placement of a target cylinder and a silicon carbide cylinder according to the present invention.

FIG. 2 is a schematic top view of the alumina setter plate and the alumina setter plate of FIG. 1.

FIG. 3 is a schematic view of two silicon carbide cartridges of the present invention stacked one on top of the other.

Wherein: 1-round hole, 2-alumina setter plate, 3-alumina setter plate, 4-target cylinder, 5-silicon carbide cylinder and 6-square hole.

Detailed Description

In order to further understand the present invention, the following detailed description will be made with reference to the following examples, which are only used for explaining the present invention and are not to be construed as limiting the scope of the present invention.

As shown in fig. 1 to 3, the present embodiment provides a sintering method for a long ITO rotary target cylinder, comprising the following steps:

s1: firstly, placing a square alumina burning bearing plate 2 with a longitudinal through round hole 1 in the middle into an oxygen atmosphere normal pressure sintering furnace, wherein the diameter of the round hole is 40 mm;

s2: then placing alumina cushion blocks 3 at intervals around the alumina setter plate, wherein the alumina cushion blocks 3 are flush with the alumina setter plate 2 in height;

s3: grinding two ends of a 1000mm target cylinder 4, then placing the target cylinder 4 on an alumina burning bearing plate 2, wherein a round hole 1 of the alumina burning bearing plate 2 faces to a through hole of the target cylinder, and the round hole 1 of the alumina burning bearing plate 2 is smaller than the through hole of the target cylinder 4;

s4: two silicon carbide cylinders 5 are stacked up and down and sleeved outside the target cylinder 2, four square holes 6 which are arranged in a cross shape are uniformly formed in the periphery of the middle of each silicon carbide cylinder 5, the silicon carbide cylinder 5 positioned below is placed on an alumina cushion block 3, and the intervals between the silicon carbide cylinders 5 and the target cylinder 4 are equal from top to bottom; the side length of the square hole 6 is 17mm, and the height of the two silicon carbide cylinders 5 which are overlapped together is equal to the height of the target cylinder 4;

s5: sintering in an oxygen atmosphere normal pressure sintering furnace by adopting a sintering curve: the furnace temperature of the oxygen atmosphere normal pressure sintering furnace is firstly preheated to 600 ℃, then the temperature is raised from 600 ℃ to 1300 ℃ for 15h, then the temperature is preserved for 15h, then the temperature is raised from 1300 ℃ to 1500-1600 ℃ for 17h, then the temperature is preserved for 35h, finally the temperature is reduced to the room temperature, and the sintering is finished.

The density and the bending degree of the ITO rotary target cylinder prepared from the steps in multiple batches are as follows:

density of	7.1317	7.1346	7.1344	7.1334	7.1343	7.1344	7.1322	7.1358	7.1319	7.132	7.1351
												Degree of curvature	1.35	0.80	0.80	1.30	0.50	1.30	1.90	1.10	0.60	0.80	1.20

Therefore, the sintering method of the embodiment has the advantages that the air inlet around the target cylinder is uniform in convection and good in temperature uniformity in the sintering process, the sintering temperature rise time is prolonged, the sintering temperature fall time is prolonged, the target cylinder is uniform in shrinkage, the ITO rotary target cylinder with the length of 750-plus-material 1000mm can be normally sintered, the straightness is good, the target cylinder is not easy to bend, cutting is not needed, machining can be directly carried out, and the problem of high difficulty in long-time rotary sintering is solved.

In the prior art, the ITO rotary target cylinder is vertically placed on a sintering bearing plate and then placed in an air inlet atmosphere sintering furnace, a certain sintering curve is set, and high-temperature controlled sintering is carried out, wherein the density and the curvature of the ITO rotary target cylinders prepared in batches by the technology are as follows:

density of	7.1381	7.1388	7.1358	7.1308	7.1275	7.1362	7.1362	7.1339	7.1332
										Degree of curvature	3.15	2.25	2.7	2.7	2.6	1.6	2.1	2.25	1.7

Such sintering has the disadvantages of uneven air inlet, uneven temperature, no long sintering target cylinder, insufficient heating time and heat preservation time of a sintering curve, uneven shrinkage of the target cylinder, severe bending of a target blank, incapability of machining, cutting of a bent part, low yield, target waste and cost increase.