A method for measuring high temperature volume resistivity of aluminum nitride ceramics

Abstract

The invention discloses a method for measuring the high-temperature volume resistivity of aluminum nitride ceramics, which belongs to the technical field of volume resistivity measurement, and includes: S1: muffle furnace program setting: adopting a segmented heating method to set the muffle furnace program; S2: test resistance: connect the sample to be tested to test the resistance, place the sample to be tested between the positive electrode and the negative electrode of the measuring instrument in the muffle furnace, and add a protective electrode for measurement, and test the resistance under the test conditions of a test voltage of 500V / mm and an electrification time of 180s; S3: volume resistivity calculation: the volume resistivity is calculated according to the following formula: ρ=Rx×A / h. The equipment used in the test method of the present application is cheap and simple to build; has good stability, repeatability and reproducibility; and is conducive to the control of product quality by enterprises of electrostatic chuck heaters.

Description

Technical Field

[0001] The invention relates to the technical field of volume resistivity measurement, and in particular to a method for measuring the high-temperature volume resistivity of aluminum nitride ceramics. Background Art

[0002] Volume resistivity indicates the degree of resistance of a material to electric current per unit volume. A high volume resistivity indicates that the material has a large resistance to electric current and is an excellent insulating material. Under the existing technology, volume resistivity is generally measured by the silver method, that is, the upper and lower surfaces of the required test sample are silvered, dried in an oven at 100°C, and then connected to a picoammeter through an insulated measuring wire for testing. Electrostatic suction heaters are used to heat treat semiconductor wafers, glass substrates, flexible substrates and other heat treatment objects at a given heating temperature. The high or low volume resistivity mainly distinguishes whether the electrostatic suction cup is a Coulomb type (volume resistivity greater than 10 12 Ω·cm) or JR type (volume resistivity between 10 8 Ω·cm to 10 12 Ω·cm), it is difficult for the electrons in the electrostatic chuck with high volume resistivity to move, the charge is difficult to release, and the detachment effect is not good. Therefore, the measurement of the high temperature volume resistivity of aluminum nitride ceramics used in electrostatic chuck heaters is an essential measurement technology for companies that make electrostatic chuck heaters and is the key to controlling product quality. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for measuring the high-temperature volume resistivity of aluminum nitride ceramics. The equipment used in the measuring method has a simple structure and low cost.

[0004] In order to solve the above technical problems, the technical solution of the present invention is:

[0005] A method for measuring the high-temperature volume resistivity of aluminum nitride ceramics, the measuring method comprising:

[0006] S1: Muffle furnace program settings:

[0007] Continuous heating can quickly obtain the approximate relationship between resistivity and temperature, while segmented heating will obtain a more accurate relationship. It is also suitable for materials with dielectric absorption. For the measurement of high-temperature volume resistivity of aluminum nitride ceramics, segmented heating is adopted to set the muffle furnace program.

[0008] S2: Test resistance:

[0009] Connect the test sample to test resistance. Place the test sample between the positive electrode and negative electrode of the tester in a muffle furnace. Add a guard electrode for measurement. Test the resistance under the test conditions of a test voltage of 500 V / mm and an electrification time of 180 s. Then calculate the volume resistivity according to the volume resistivity calculation formula.

[0010] S3: Calculation of volume resistivity:

[0011] The volume resistivity is calculated according to the following formula:

[0012] ρ=Rx×A / h

[0013] Where:

[0014] P is the volume resistivity, in ohm-centimeter (Ω·cm);

[0015] Rx is the volume resistance in ohms (Ω);

[0016] A is the effective area of ​​the measuring electrode, in square centimeters (cm2);

[0017] h is the thickness of the sample to be tested, in centimeters (cm).

[0018] Preferably, the positive electrode and the negative electrode are both disc-shaped silver blocks with a diameter of 30 mm, and the protective electrode is a disc-shaped silver block with a diameter of 50 mm.

[0019] Preferably, the positive electrode is arranged below the sample to be tested, the negative electrode is arranged above the sample to be tested, the protective electrode is arranged between the negative electrode and the sample to be tested, and aluminum nitride ceramic is arranged above the negative electrode, and the aluminum nitride ceramic is used to firmly fix the sample to be tested between the positive electrode and the negative electrode.

[0020] Preferably, the wire used for resistance measurement is made of metal nickel wire with good strength and mechanical properties at high temperatures and corrosion resistance, and is introduced into the muffle furnace cavity through the hole in the muffle furnace wall avoiding the thermocouple to connect with the positive electrode and the negative electrode.

[0021] Preferably, the measuring instrument is a high resistance meter.

[0022] The above technical solution has the following beneficial effects:

[0023] 1. The equipment used in this measurement method is cheap and easy to build;

[0024] 2. Good measurement stability, repeatability and reproducibility;

[0025] 3. It is beneficial for electrostatic chuck heater companies to control product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The present invention is a schematic structural diagram of the electrode arrangement of a method for measuring the high-temperature volume resistivity of aluminum nitride ceramics. DETAILED DESCRIPTION

[0027] The specific embodiments of the present invention are further described below in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0028] A method for measuring the high temperature volume resistivity of aluminum nitride ceramics comprises the following steps:

[0029] S1: Muffle furnace program settings:

[0030] Continuous heating can quickly obtain the approximate relationship between resistivity and temperature, while segmented heating will obtain a more accurate relationship. It is also suitable for materials with dielectric absorption. For the measurement of high-temperature volume resistivity of aluminum nitride ceramics, segmented heating is adopted. The muffle furnace program is set, and the temperature is increased segment by segment to measure the high-temperature volume resistivity of aluminum nitride ceramics.

[0031] S2: Test resistance:

[0032] refer to Figure 1 , connect the test sample 1 to test the resistance, place the test sample 1 between the positive electrode 2 and the negative electrode 4 of the measuring instrument in the muffle furnace, and add the protective electrode 3 for measurement, test the resistance under the test conditions of a test voltage of 500V / mm and an electrification time of 180s, and then calculate the volume resistivity according to the volume resistivity calculation formula;

[0033] S3: Calculation of volume resistivity:

[0034] The volume resistivity is calculated according to the following formula:

[0035] ρ=Rx×A / h

[0036] Where:

[0037] P is the volume resistivity, in ohm-centimeter (Ω·cm);

[0038] Rx is the volume resistance in ohms (Ω);

[0039] A is the effective area of ​​the measuring electrode, in square centimeters (cm2);

[0040] h is the thickness of the sample to be tested, in centimeters (cm);

[0041] After measuring the volume resistance, the effective area A of the measuring electrode and the thickness h of the sample 1 to be tested are calculated, and the volume resistivity of the sample 1 to be tested can be calculated by substituting them into the above formula;

[0042] The positive electrode 2 and the negative electrode 4 are both disc-shaped silver blocks with a diameter of 30 mm. The positive electrode 2 and the negative electrode 4 have a certain thickness. At the same time, the sample 1 to be tested is also a block with a certain thickness. The relationship between the thickness and the volume resistivity is as shown in the above formula. The protective electrode 3 is a disc-shaped silver block with a diameter of 50 mm.

[0043] The positive electrode 2 is arranged below the sample 1 to be tested, the negative electrode 4 is arranged above the sample 1 to be tested, the protective electrode 3 is arranged between the negative electrode 4 and the sample 1 to be tested, and an aluminum nitride ceramic 5 is arranged above the negative electrode 4, and the aluminum nitride ceramic 5 is used to firmly fix the sample to be tested between the positive electrode 2 and the negative electrode 4;

[0044] The wire used for resistance measurement is made of metal nickel wire with good strength and mechanical properties at high temperature and corrosion resistance, and is introduced into the muffle furnace cavity from the hole in the muffle furnace wall avoiding the thermocouple and connected to the positive electrode 2 and the negative electrode 4, so as to measure the volume resistance;

[0045] The measuring instrument is a high resistance meter. This application uses a muffle furnace RGX1700-30 to provide a temperature environment and a high resistance meter SM7110 to test the resistance;

[0046] The measurement method of this application has the following advantages:

[0047] 1. The equipment used in this measurement method is cheap and easy to build;

[0048] 2. Good measurement stability, repeatability and reproducibility;

[0049] 3. It is beneficial for electrostatic chuck heater companies to control product quality.

[0050] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments are made without departing from the principles and spirit of the present invention, and still fall within the scope of protection of the present invention.

Claims

1. A method for measuring the high temperature volume resistivity of aluminum nitride ceramics, characterized in that: The measuring method comprises: S1: Muffle furnace program settings: Continuous heating can quickly obtain the approximate relationship between resistivity and temperature, while segmented heating will obtain a more accurate relationship. It is also suitable for materials with dielectric absorption. For the measurement of high-temperature volume resistivity of aluminum nitride ceramics, segmented heating is adopted to set the muffle furnace program. S2: Test resistance: Connect the test sample to test resistance. Place the test sample between the positive electrode and negative electrode of the tester in a muffle furnace. Add a guard electrode for measurement. Test the resistance under the test conditions of a test voltage of 500 V / mm and an electrification time of 180 s. Then calculate the volume resistivity according to the volume resistivity calculation formula. S3: Calculation of volume resistivity: The volume resistivity is calculated according to the following formula: ρ=Rx×A / h Where: P is the volume resistivity, in ohm-centimeter (Ω·cm); Rx is the volume resistance in ohms (Ω); A is the effective area of ​​the measuring electrode, in square centimeters (cm2); h is the thickness of the sample to be tested, in centimeters (cm).

2. The method for measuring the high temperature volume resistivity of aluminum nitride ceramics according to claim 1, characterized in that: The positive electrode and the negative electrode are both disc-shaped silver blocks with a diameter of 30 mm, and the protective electrode is a disc-shaped silver block with a diameter of 50 mm.

3. The method for measuring the high temperature volume resistivity of aluminum nitride ceramics according to claim 2, characterized in that: The positive electrode is arranged below the sample to be tested, the negative electrode is arranged above the sample to be tested, the protective electrode is arranged between the negative electrode and the sample to be tested, and aluminum nitride ceramic is arranged above the negative electrode. The aluminum nitride ceramic is used to firmly fix the sample to be tested between the positive electrode and the negative electrode.

4. The method for measuring the high temperature volume resistivity of aluminum nitride ceramics according to claim 1, characterized in that: The wire used for resistance measurement is made of metal nickel wire with good strength and mechanical properties at high temperature and corrosion resistance, and is introduced into the muffle furnace cavity through the hole in the muffle furnace wall avoiding the thermocouple to connect with the positive electrode and the negative electrode.

5. The method for measuring the high temperature volume resistivity of aluminum nitride ceramics according to claim 1, characterized in that: The measuring instrument is a high resistance meter.

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