Technical application of high-precision thick film screen printing in ceramic sensors

A sensor is a device used to sense and detect physical information and convert it into electrical signals.Due to its advantages of miniaturization, digitization, and intelligence, it is widely used in automobile industry batteries, medical fields (adding blood glucose meter links), environmental testing, aerospace and other application fields.

Sensors can be divided into integrated sensors, thin film sensors, thick film sensors, ceramic sensors, etc. according to process classification.Among them, ceramic sensors are sensors made of ceramic materials. Because ceramic materials have the advantages of high sensitivity, good linear response, high temperature resistance, corrosion resistance, and high strength, they have become an ideal material for making ceramic sensors in recent years.
In the production process of ceramic sensors, the first step is to process the ceramic materials: ① Sieve the ceramic powder to ensure uniform particles.② Processed into the required shape and size, the most common methods are molding, injection molding, die casting and extrusion.③Drying and sintering, the time and temperature need to be determined according to the characteristics and shape of the ceramic material.④Clean to remove surface impurities and dirt.⑤ Passivation treatment uses a certain concentration of oxidizing acid or alkali to cause an oxidation reaction between metal and oxygen on the sensor surface to form an oxide film.
After ceramic material processing is the key process for making ceramic sensors: thick film screen printing, which requires printing the electrode layer, resistive layer, and encapsulation layer respectively.Due to the need to ensure high precision, uniform film thickness, resistance stability, etc., it is necessary to use high-precision thick film printing equipment (add 200A-CCD model article link).In the field of thick film screen printing technology in the field of sensors, especially in the field of ceramic sensors, a variety of models developed and produced by Jianyu Screen Printing have been widely used, and it has rich technical reserves in various sensor screen printing technologies.The following is a brief explanation of the printing process of thick film screen printing technology on ceramic sensors.

Thick film screen printing process
Product printing components: electrode layer, resistance layer, encapsulation layer
Requirements and functions of the stencil: cast mesh frame pulled composite stencil, tension 30N, angle 22.5; electrode layer stencil mesh 325 mesh, used for line conductivity and welding points; resistance layer stencil mesh 325 mesh, according to The product is required to meet the required resistance range; the mesh number of the encapsulating mesh is 325, which is used to protect the underlying lines and insulate from the air.
Printing environment: purified workshop, indoor temperature between 22-26 degrees, relative humidity around 65%.
Printing process: first print the electrode layer, then print the resistive layer, and finally print the encapsulation layer.
Printing requirements: Use a high-precision screen printing machine, adopt a CCD automatic alignment printing platform, print the jig plate according to the product specifications, the screen distance is 1.2mm, and the printing air pressure is 1.5kg (the printing air pressure must be controllable and adjustable).
Sintering: Every time printing is completed, it needs to be dried, baked at 120-150 degrees for 5-10 minutes, and then entered into a high-temperature sintering furnace for sintering.