Ceramic substrates are the special process plates that copper foil bonds directly to the surface of alumina (Al2O3) or aluminium nitride (AlN) ceramic substrates (single-sided or double-sided) at high temperature. The ultra-thin composite substrate has excellent electrical insulation, high thermal conductivity, excellent solderability and high adhesion strength. It can etch various patterns like PCB board, and has great current carrying capacity. Therefore, ceramic substrates have become the basic materials of high-power power electronic circuit structure technology and interconnection technology.

◆机械应力强，形状稳定；高强度、高导热率、高绝缘性；结合力强，防腐蚀。 Strong mechanical stress, stable shape; high strength, high thermal conductivity, high insulation; strong bonding force, anti-corrosion. ◆ 较好的热循环性能，循环次数达5万次，可靠性高。 _Better thermal cycle performance, 50,000 cycles, high reliability. ◆与PCB板(或IMS基片)一样可刻蚀出各种图形的结构；无污染、无公害。 Like PCB board (or IMS substrate), it can etch the structure of various graphics; it is pollution-free and pollution-free. ◆使用温度宽-55℃～850℃；热膨胀系数接近硅，简化功率模块的生产工艺。 Use temperature wide - 55 ~850 C, thermal expansion coefficient close to silicon, simplify the production process of power module.

It takes a few weeks to create the ICT fixture and do its programming. A fixture can either be vacuum or press-down. Vacuum fixtures give better signal reading versus the press-down type. On the other hand, vacuum fixtures are expensive because of their high manufacturing complexity. The bed of nails or in-circuit tester is the most common and popular in the contract manufacturing environment.

ICT provides OEM customer such benefits as: Although a costly fixture is required, ICT covers 100% testing so that all power and ground shorts are detected. ICT testing does power up testing and eliminates customer debug needs to almost ZERO. ICT does not take a very long time to perform, for example if flying probe takes 20 minutes or so, ICT for the same time might take a minute or so. Checks and detects shorts, opens, missing components, wrong value components, wrong polarities, defective components and current leakages in the circuitry. Highly reliable and comprehensive test catching all manufacturing defects, design faults, and flaws. Testing platform is available in Windows as well as UNIX, thus making it slightly universal for most testing needs. Test development interface and operating environment is based on standards for an open system with fast integration into an OEM customer’s existing processes. ICT is the most tedious, cumbersome, and expensive type of testing. However, ICT is ideal for mature products requiring volume production. It runs the power signal to check voltage levels and resistance measurements at different nodes of the board. ICT is excellent at detecting parametric failures, design related faults and component failures.