High-temperature ceramic wafer heating disc

Abstract

The utility model relates to the technical field of semiconductor manufacturing, in particular to a high-temperature ceramic wafer heating disc. The high-temperature ceramic wafer heating disc at least comprises a ceramic substrate which is smooth in surface and uniform in wall thickness, one surface of the ceramic substrate is a heating surface, the other surface of the ceramic substrate is a resistance tape with a certain path, and the resistance tape is arranged in a path groove formed in the ceramic substrate. The bottom of the path groove is a plane subjected to precision machining, the width of the plane is 0.2 mm larger than that of the resistance tape, the depth of the path groove is the thickness value of the resistance tape plus 3.0 mmm, and a ceramic cover plate completely covering the resistance tape is further arranged in the path groove. A heating source of the high-temperature ceramic wafer heating disc is a high-temperature resistance tape formed by precise cutting, the high-temperature resistance tape is made of tungsten or molybdenum, the resistance tape is processed and formed according to the structure of the heating disc and finite element analysis of a temperature field, and the high-temperature ceramic wafer heating disc has the advantage that the heating temperature of a wafer is high and uniform.

Description

Technical Field

[0001] The utility model relates to semiconductor manufacturing, in particular to a high-temperature ceramic wafer heating plate. Background Art

[0002] With the continuous advancement of science and technology, the market demand for semiconductors continues to increase. Wafers are the basic materials for manufacturing semiconductor chips. Wafer heating technology is a very important key technology in the advanced electronic manufacturing industry. It is widely used in chip packaging and integrated circuit equipment. The purpose is to reduce the failure rate of components caused by factors such as uneven temperature, falling, vibration, etc. during the use of products, thereby extending the service life of products. Therefore, as the key and core of electronic packaging technology, the improvement of heating technology is directly related to the quality of packaging technology.

[0003] In the process of wafer production, the temperature of the wafer needs to reach a preset temperature of 500℃ or above, and a certain temperature uniformity of less than ±1℃ must be ensured. If the temperature is lower than the preset temperature or the temperature is uneven, it is easy to cause cracking and increase the defect rate. Therefore, the wafer heating plate has a vital impact on the wafer production process. However, the current wafer heating plate is prone to uneven temperature, poor wafer production effect, low yield rate and other problems. Therefore, the control of the temperature uniformity of the wafer heating plate needs to be further improved to effectively ensure the wafer process effect.

[0004] There are two main types of wafer heating plates on the market:

[0005] 1. Aluminum wafer heating plate. The production method of this aluminum heating plate is to bend the electric heating tube with a diameter of more than 6 mm along a certain path, and the electric heating tube is buried with a spiral heating wire; the electric heating tube is buried in an aluminum plate with a certain path groove, and covered with a cover plate; the cover plate is welded to make the electric heating tube completely placed inside the aluminum plate. The disadvantages of this structure of the wafer heating plate are: due to the inevitable uneven wire displacement of the spiral heating wire during the drawing process and after the tube shrinkage, this leads to uneven temperature; since the electric heating tube needs to have a minimum bending radius, the upper surface temperature close to the electric heating tube is high and the upper surface far away will be very low, which is also the reason for the uneven surface temperature of the heating plate; due to the physical properties of the aluminum material itself, the maximum heating temperature does not exceed 450°C.

[0006] 2. Ceramic wafer heating plate. The existing ceramic wafer heating plate has a heating wire that rotates spirally from the center to the periphery. The distribution of the heating wire in the heating plate is not uniform enough to achieve the purpose of uniform heating and cannot meet the high-precision heating requirements of the wafer. However, high-precision heating is crucial to the semiconductor process.

[0007] The above-mentioned prior art wafer heater cannot heat uniformly at a constant temperature. Utility Model Content

[0008] The utility model aims to solve the above defects and provides a high-temperature ceramic wafer heating plate and a preparation method thereof.

[0009] In order to overcome the defects existing in the background technology, the technical solution adopted by the utility model to solve its technical problems is: this high-temperature ceramic wafer heating plate includes at least one ceramic substrate with a smooth surface and uniform wall thickness, one side of the ceramic substrate is a heating surface, and the other side is a resistance belt designed with a certain path, the resistance belt is placed in a path groove set on the ceramic substrate, the bottom of the path groove should be a precisely machined plane, and its width is 0.2mm larger than the width of the resistance belt, the depth of the path groove is the thickness of the resistance belt plus 3.0mm, and a ceramic cover plate that completely covers the resistance belt is also provided in the path groove.

[0010] According to another embodiment of the present invention, the thickness of the ceramic substrate is no less than 14 mm.

[0011] According to another embodiment of the utility model, the two ends of the high-temperature resistance belt are further connected to power electrodes. The high-temperature resistance belt is a high-temperature heating material tungsten or molybdenum. The distribution of the resistance belt on the ceramic substrate is that the center distance of each circle will gradually decrease from the inside to the outside, and the reduction range is controlled between 2-10mm. The center distance between the two outermost circles is 2.0-4.0 times the width of the resistance belt, presenting a tight outside and loose inside structure distribution.

[0012] According to another embodiment of the utility model, the power supply electrode is further placed in a support tube, and the support tube is fixed on a ceramic substrate.

[0013] According to another embodiment of the utility model, the material of the ceramic cover plate is the same as that of the ceramic substrate, and the processing method is also the same.

[0014] The beneficial effect of the utility model is that the heat source of the high-temperature ceramic wafer heating plate is a high-temperature resistance belt that has been precisely cut and formed. The material of the ceramic wafer heating plate is tungsten or molybdenum. The resistance belt is processed and formed based on the finite element analysis of the heating plate structure and temperature field, and has the advantage of making the wafer heated to a high and uniform temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0016] Figure 1 It is a structural schematic diagram of the utility model;

[0017] Figure 2 It is a structural schematic diagram of the side view of the utility model;

[0018] Figure 3It is a structural schematic diagram of an exploded view of the side view of the utility model;

[0019] Wherein: 101, ceramic substrate, 102, path groove, 201, resistance band, 202, power electrode, 301, ceramic cover plate, 401, support tube. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the embodiments of the utility model clearer, the technical solution in the embodiments of the utility model will be clearly and completely described in combination with the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. The embodiments in the basic utility model and all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] like Figure 1-3 As shown in the figure, at least one ceramic substrate 101 with a smooth surface and uniform wall thickness is included. One side of the ceramic substrate 101 is a heating surface, and the other side is a resistance belt 201 designed with a certain path. The resistance belt 201 is placed in a path groove 102 set on the ceramic substrate 101. The bottom of the path groove 102 should be a precisely machined plane, and its width is 0.2mm larger than the width of the resistance belt 201, so that the resistance belt 201 can be smoothly buried. The design of this path groove should be combined with the temperature field distribution of the resistance belt 201 on the entire surface of the heating disk, and the corresponding installation holes should be avoided. The depth of the path groove 102 is the thickness of the resistance belt 201 plus 3.0mmm. A ceramic cover plate 301 that completely covers the resistance belt 201 is also provided in the path groove 102.

[0022] The ceramic substrate 101 is a special high-temperature resistant ceramic, which is an aluminum nitride ceramic. After molding, casting, isostatic pressing, and sintering at 1700°C, the sintered semi-finished product is then precision-machined to the required shape and geometric dimensions. In order to ensure the uniformity of temperature and the strength of the heating plate surface, the thickness of the ceramic substrate 101 is not less than 14 mm.

[0023] Both ends of the high-temperature resistance belt 201 are connected to the power supply electrodes 202. The high-temperature resistance belt 201 is a high-temperature heating material tungsten or molybdenum. The material of the resistance belt 201 can be heated to a temperature of more than 1400°C and up to 2000°C, and has the ability to withstand high-temperature heating. The resistance belt 201 is formed by precision cutting of a tungsten plate or a molybdenum plate of a certain thickness. In order to ensure the uniformity of the temperature, a temperature field analysis is required. The distribution of the resistance belt 201 on the ceramic substrate 101 is that the center distance of each circle from the inside to the outside will gradually decrease, and the reduction range is controlled between 2-10mm. The center distance of the two outermost circles is 2.0-4.0 times the width of the resistance belt 201, and the structure is tight outside and loose inside.

[0024] The material of the ceramic cover plate 301 is the same as that of the ceramic substrate 101, and the processing method is also the same. The processing is mainly to ensure the accuracy of the processing size.

[0025] The preparation method of the high temperature ceramic wafer heating plate comprises:

[0026] The first step is to mold aluminum nitride ceramics, cast them, isostatically press them, and then sinter them at 1700° C., and then precisely process the sintered semi-finished products into ceramic substrates 101 with the required geometric dimensions;

[0027] Step 2: Place the prepared resistor strip 201 evenly into the path groove 102 of the ceramic substrate 101;

[0028] Step 3: Cover the ceramic cover plate 301 evenly on the surface of the resistor belt 201 and compact and press it tightly, so that the resistor belt 201 is completely in close contact with the bottom of the substrate path groove to increase the heat transfer effect;

[0029] Step 4: weld or re-sinter the ceramic cover plate 301 to completely fuse the ceramic cover plate 301 and the ceramic substrate 101 into one, and completely seal the resistance band 201 in the path groove 102 of the ceramic substrate 101, thereby ensuring thermal conductivity and increasing temperature uniformity.

[0030] The ceramic cover plate 301 is replaced with ceramic powder, and the ceramic cover plate 301 and the ceramic substrate 101 are completely melted into one by sintering, so that the resistance band 201 is completely and tightly filled in the path groove 102 of the ceramic substrate 101 .

[0031] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A high temperature ceramic wafer heating plate, characterized in that: The invention comprises at least one ceramic substrate (101) with a smooth surface and uniform wall thickness. One side of the ceramic substrate (101) is a heating surface, and the other side is a resistance band (201) designed with a certain path. The resistance band (201) is placed in a path groove (102) provided on the ceramic substrate (101). The bottom of the path groove (102) should be a precisely machined plane, and its width is 0.2 mm greater than the width of the resistance band (201). The depth of the path groove (102) is the thickness of the resistance band (201) plus 3.0 mm. A ceramic cover plate (301) that completely covers the resistance band (201) is also provided in the path groove (102).

2. A high temperature ceramic wafer heating plate as claimed in claim 1, characterized in that: The thickness of the ceramic substrate (101) is not less than 14 mm.

3. A high temperature ceramic wafer heating plate as claimed in claim 1, characterized in that: The two ends of the resistance band (201) are connected to the power supply electrodes (202). The high-temperature resistance band (201) is a high-temperature heating material, tungsten or molybdenum. The distribution of the resistance band (201) on the ceramic substrate (101) is such that the center distance of each circle gradually decreases from the inside to the outside, and the reduction range is controlled between 2 and 10 mm. The center distance between the two outermost circles is 2.0 to 4.0 times the width of the resistance band (201), presenting a tight outside and loose inside structure distribution.

4. A high temperature ceramic wafer heating plate as claimed in claim 3, characterized in that: The power supply electrode (202) is placed in a support tube (401), and the support tube (401) is fixed on a ceramic substrate (101).

5. A high temperature ceramic wafer heating plate as claimed in claim 1, characterized in that: The material of the ceramic cover plate (301) is the same as that of the ceramic base plate (101), and the processing and forming process methods are also the same.

Images