Military, aerospace and many high-reliability optoelectronics application work with large complex hybrids. Hybrids are to be differentiated from single chip applications: hybrids are multi-chip, complex and require sophisticated packaging equipment to execute assembly.

Hybrids are large, and this usually presents a problem to the otherwise less complex assembly systems.

Small signals make up the great majority of hybrid packages. These contain digital and analog circuits with aspects that do not require sophisticated frequency of operation or power dissipation. They can take any form.

• Flat pack - early form of hybrid package
• Plug in - with leads existing through the base
• Packages without leads (leafless chip carriers (LLC)) - used in packaging hybrid microcircuits

Hybrid microcircuits includes the traditional thick and thin film circuits, and multi-chip modules (MCMs) assembled onto a ceramic substrate.

Examples of large complex hybrids:

• MEMS (Micro-Electronic-Mechnical-Systems)
• MOEMS