Modern electronic equipment such as televisions, telephones, radios and computers are generally constructed of solid state devices. Solid state devices are preferred in electronic equipment because they are extremely small and relatively inexpensive. Additionally, solid state devices are very reliable because they have no moving parts, but are based on the movement of charge carriers.
Solid state devices include transistors, capacitors, resistors and the like. One type of transistor is complementary metal oxide semiconductor (CMOS) transistors. CMOS transistors are a pair of transistors of opposite type used together. CMOS transistors may be used for low-dissipation logic circuits and the like.
The gates of CMOS transistors are typically constructed of a neutral material and later doped to opposite types such as n-type and p-type. The neutral gate material is generally a material that will not adversely affect the performance of either type of gate. As a result, the gate material may not be particularly well suited for either type gate.