CN-116926471-B - Platinum film and manufacturing method thereof

Abstract

A method for preparing a Pt film includes chemically and mechanically polishing a ceramic substrate with polishing liquid to obtain a ceramic substrate with a predefined roughness, depositing Pt film on the ceramic substrate by magnetron sputtering at predefined substrate temp, and annealing. The invention prepares the platinum film with the advantages of thin thickness, low sheet resistance, high uniformity, low cost and the like by adopting the chemical mechanical polishing treatment and the multiple sputtering mode, realizes that the electrical property of the platinum film is equivalent to the property of the thick film under the condition of thinner thickness, and reduces the production cost while ensuring good performance. Therefore, the sensor is applied to the resistance temperature sensor, thereby being beneficial to meeting the requirement of the resistance temperature sensor product on the accurate measurement of the ambient temperature, reducing the production cost of the resistance temperature sensor and improving the production efficiency.

Inventors

• LV WEIMING
• FAN YAMING
• WANG YIQUN
• SHI WENHUA
• ZENG ZHONGMING
• ZHANG BAOSHUN

Assignees

• 中国科学院苏州纳米技术与纳米仿生研究所

Dates

Publication Date

20260508

Application Date

20220402

Claims (6)

1. 1. A method for producing a platinum film, comprising: Pretreatment, namely performing chemical mechanical polishing treatment on the ceramic substrate by using polishing liquid to obtain the ceramic substrate with preset roughness; Coating, namely depositing a platinum film on the ceramic substrate by utilizing a magnetron sputtering method at a preset substrate temperature; and (3) heat treatment: annealing the platinum film; the specific process for forming the platinum film on the ceramic substrate by deposition through the magnetron sputtering method comprises the following steps: Continuously introducing working gas with preset gas flow by taking metal platinum as a target material; Under the working gas atmosphere, performing first pre-sputtering and cooling after the first sputtering on the ceramic substrate in sequence; under the working gas atmosphere, performing second pre-sputtering and cooling after the second sputtering on the ceramic substrate in sequence; sequentially performing third pre-sputtering and third sputtering on the ceramic substrate in the working gas atmosphere; wherein the platinum film is grown in each sputtering, but is not grown in each pre-sputtering; wherein the sputtering time of the second pre-sputtering and the third pre-sputtering is 5s, and the sputtering time of the first sputtering is 30s; In the coating step, the temperature of the substrate is 280-320 ℃, the vacuum degree of magnetron sputtering is 3.0 multiplied by 10 -4 Pa~9.0×10 -4 Pa, and the direct current power of the magnetron sputtering is 260-340W; the working gas is argon, the gas flow of the working gas is 136sccm, and the sum of the time of the first sputtering, the second sputtering and the third sputtering is 224 s-245 s.
2. 2. The method according to claim 1, wherein the pretreatment method specifically comprises: placing a ceramic substrate in a grinder, and grinding the ceramic substrate by using polishing solution; Sequentially carrying out ultrasonic cleaning on the ceramic substrate by using an acetone solution and an isopropanol solution; And repeatedly cleaning the ceramic substrate by using deionized water, and drying to obtain the ceramic substrate with the preset roughness.
3. 3. The manufacturing method according to claim 2, wherein the polishing liquid is a diamond polishing liquid, the size of diamond particles in the diamond polishing liquid is 2-4 μm, and the grinding time is 6h.
4. 4. The method according to claim 1, wherein in the heat treatment step, the annealing temperature is 450 ℃ to 550 ℃, the annealing time is 1.5h to 2.5h, and the annealing atmosphere is nitrogen.
5. 5. A platinum film formed by the method according to any one of claims 1 to 4.
6. 6. The platinum film according to claim 5, wherein the platinum film has a thickness of 60nm to 120nm, a sheet resistance of 1.1 Ω to 1.6 Ω/≡, and uniformity of the platinum film is <1.5%.

Description

Platinum film and manufacturing method thereof Technical Field The invention belongs to the field of temperature sensors, and particularly relates to a platinum film and a manufacturing method thereof. Background The resistance temperature sensor is an electronic element which measures the temperature of the environment by utilizing the characteristic that the resistance of a sensitive material changes along with the temperature change and the resistance and the temperature have stable corresponding relation. The metal platinum has the advantages of high sensitivity, high precision, good linearity, large temperature measuring range, good stability and the like, and is widely applied to the fields of manufacturing platinum resistance temperature sensors and the like. The platinum temperature sensor is mainly manufactured by adopting a wire winding process, a thick film process and a thin film process. The wire winding process is characterized in that platinum wires are respectively wound on a ceramic skeleton, a glass skeleton and a mica skeleton and then are processed by a complex process, but the process is complex, the platinum metal which needs to be consumed is increased to cause corresponding cost increase, the process is gradually replaced by a thick film process, the thick film process is processed by utilizing processes of screen printing platinum sizing agent, sintering, laser resistance adjustment and the like on a ceramic substrate, a large amount of platinum sizing agent is adhered to a screen frame and a scraper in the screen printing process, the platinum sizing agent is wasted during cleaning, the printing thickness is generally more than 10 mu m, further the production cost is increased, in addition, the high energy of a laser beam can cause a large-area platinum film to be subjected to high temperature effect in the laser resistance adjustment process, further the platinum film structure is changed and the film sheet resistance is changed, and the surrounding film layer materials are ablated to influence the accuracy and stability of the platinum film resistance, so the thick film printing process is adopted to produce the platinum temperature sensor, and the defects of high production cost, low production efficiency, large product volume, poor resistance accuracy and the like are overcome. With the rapid development of microelectronic technology integration, the industrial industry has provided the requirements of small volume, quick response, high precision, convenient system integration design and the like for platinum resistance temperature sensors, and the wire winding process and the thick film process obviously cannot completely meet the requirements. The thin film technology is prepared by depositing the platinum thin film with the micro-nano thickness on the ceramic substrate, the defects existing in the original technology are overcome, in addition, the platinum thin film has the characteristics of small heat capacity and large heat conductivity, the real temperature of an object to be measured can be accurately and rapidly measured, the method is suitable for occasions such as narrow areas, rapid measurement, high-temperature resistance elements and the like, and high attention of the scientific community and industry is obtained. Notably, the platinum film is a core part of the platinum resistance temperature sensor, and the performance of the platinum film directly influences the accuracy of device temperature detection. However, in the existing film process, the problems of larger thickness, poor performance, high cost and the like of the platinum film still exist. Disclosure of Invention In order to solve the problems in the prior art, the invention provides a platinum film and a manufacturing method thereof. According to the manufacturing method of the platinum film provided by the aspect of the embodiment of the invention, the manufacturing method comprises the steps of preprocessing, namely performing chemical mechanical polishing treatment on a ceramic substrate by using polishing solution to obtain the ceramic substrate with the preset roughness, plating, namely depositing and forming the platinum film on the ceramic substrate by using a magnetron sputtering method at the preset substrate temperature, and performing annealing treatment on the platinum film. Further, the pretreatment method specifically comprises the steps of placing a ceramic substrate in a grinder, grinding the ceramic substrate by using polishing solution, sequentially carrying out ultrasonic cleaning on the ceramic substrate by using an acetone solution and an isopropanol solution, repeatedly cleaning the ceramic substrate by using deionized water, and drying by blow to obtain the ceramic substrate with preset roughness. Further, the polishing solution is a diamond polishing solution, the size of diamond particles in the diamond polishing solution is 2-4 mu m, and the grinding time is 6 hours. Further