Space-class printed circuit boards (PCBs) require specialized substrates that can withstand the harsh conditions of space. The most commonly used substrates are listed below.
1. Alumina (Al2O3) and aluminum nitride (AlN) ceramics. The low coefficients of thermal expansion of ceramics make PCBs exceptionally stable in extreme temperatures. 2. Glass-ceramic materials, including low-temperature fired ceramics (LTCC) have excellent electrical properties, minimal thermal expansion, and high thermal conductivity. 3. Polyimide is a flexible and lightweight polymer. Such substrates are well suited for flexible printed circuit boards. They also have good thermal stability, which allows them to withstand temperature variations. 4. Radiation-resistant materials. For example, epoxy laminates and copper alloys: - The increased resistance of epoxy laminates to degradation by radiation provides durability and reliability for space printed circuit boards. - Copper-tungsten (CuW) and copper-molybdenum (CuMo) alloys increase the board's resistance to degradation. 5. Copper foil is vital to the functionality of space-class PCBs. Conductive layers are used to facilitate the transmission of electrical signals. High performance copper foils are used in space class PCBs to ensure optimum signal integrity and reduce signal loss.