The transistor may be one of many varieties of bipolar transistors or field-effect transistors. The invention and development of the earliest transistors at Bell led to transistor radios. Schottky diodes are often used as antisaturation clamps in Schottky transistors. Some common electronic components are capacitors, inductors, resistors, diodes, transistors, etc. A NAND gate is made using transistors and junction diodes. Their circuitry used three Philco germanium PNP alloy-fused junction audio frequency transistors. Computers were invented and later miniaturized using transistors and integrated circuits. Elemental germanium is used as a semiconductor in transistors and various other electronic devices. CMOS is a combination of two MOSFET transistors. The circuit consists of mainly Bipolar transistors. It was a near pocket-sized radio featuring 4 transistors and one germanium diode. Below are several non-silicon substitutes in the fabrication of small nanometer transistors. Bipolar transistors and thyristors are currently developed. These did not have the drawbacks of the mesa silicon transistors. The 608 contained more than 3,000 germanium transistors.