base material
The base material is the substrate material of printed circuit boards or integrated circuits. Printed circuit boards use hard paper, glass cloth or cotton paper as base material, which is reinforced by resins such as phenol, epoxy, Teflon and polymers.
This base material is laminated with a copper layer. The base material can be rigid or flexible in the case of flexible printed circuit boards. The uncoated base material is laminated with a conductive surface of copper.
Base material must have high reliability, meet certain thermal and dielectric properties, and be flame retardant( FR). The dielectric constant is specified at a frequency of 1 MHz. For classification purposes, base materials are divided into FR classes. In addition, high requirements are placed on the expansion behavior and material decomposition during temperature changes and.
The base material of chips usually consists of high-purity silicon. The chip material is doped with foreign atoms and thus acquires the semiconductor properties with free electrons and holes as charge carriers.