Materials are typically classified by function: conductors and semiconductors for electronic transport; insulators and dielectrics for isolation and capacitive elements; optical materials for light emission or detection; energy materials for batteries and capacitors; and structural materials for mechanical support. Key properties include electrical conductivity or band structure, dielectric constant, charge mobility, optical bandgap, thermal conductivity, mechanical strength, chemical stability, and compatibility with fabrication processes.
Common devicematerials include silicon and silicon dioxide for conventional electronics; compound semiconductors such as gallium arsenide and indium phosphide; conductors like copper and aluminum; dielectrics such as hafnium oxide and silicon nitride; polymer dielectrics and organic semiconductors for flexible electronics; and energy materials such as lithium iron phosphate and lithium cobalt oxide. Advanced examples cover perovskites for photovoltaics, organic light-emitting and organic photovoltaic materials, and two-dimensional materials like graphene and transition metal dichalcogenides. Packaging materials include epoxy resins and encapsulants.
Manufacture and integration involve thin-film deposition, etching, lithography, doping, and bonding techniques, followed by packaging and reliability testing. Material selection balances performance with manufacturability, cost, and environmental impact. Reliability concerns include electromigration, diffusion at interfaces, thermal expansion mismatch, and chemical degradation. Standards and characterization protocols guide material screening and device qualification.
Environmental and regulatory considerations influence devicematerial choices, emphasizing lead-free solders, RoHS compliance, recyclability, and sustainable supply chains. Ongoing research seeks materials with higher efficiency, improved stability under operating conditions, and lower processing temperatures to enable new device architectures.