Atomate Reveals Carbon Nanotube High Power Diodes, Rectifiers, Varistors, and Thyristors

In U.S. Patent 7,622,732, Atomate Inc (Simi Valley, CA) inventor Thomas W. Tombler Jr. discloses the use of single wall carbon nanotube transistors, rectifiers, diodes and other applications to control power to circuits in electronic devices such as laptop computers, cellular telephones and computer chips used in aviation and automobiles.

Transistors or rectifying devices using carbon nanotubes may be used in various circuits of electronic systems including circuitry for the rapid recharging of the battery cells and voltage conversion, including DC-DC conversion and AC-DC conversion. For example, each laptop power supply typically has eight power transistors. Atomate transistors may be used in circuitry for driving the screen of the system. The screen may be a flat panel display such as a liquid crystal display (LCD), plasma display, or organic light emitting diode (OLED) display. SWNT transistors  may be used in circuitry for the wireless operation of the system such as circuitry for wireless networking (e.g., Wi-Fi, 802.11a, 802.11b, 802.11g, or 802.11n) or other wireless connectivity (e.g., Bluetooth)

FIG. 6 shows an Atomate DC-to-AC inverter circuit using carbon nanotube (NT) transistors.

A specific application of a single wall carbon nanotube (SWNT) device is as a power diode, a type of diode capable of passing relatively high currents compared to standard diodes. Atomate's patent reveals diodes, silicon-controlled rectifiers, and other related devices built with carbon nanotubes, and methods for making such devices by chemical vapor deposition synthesis and liquid deposition.  

Heterostructure devices incorporating carbon nanotube technology to implement rectifying devices include diodes, rectifiers, silicon-controlled rectifiers, varistors, and thyristors. A rectifying device includes carbon nanotube and nanowire elements. The carbon nanotubes may be single-walled carbon nanotubes. The devices may be formed using parallel pores of a porous structure. The porous structure may be anodized aluminum oxide or another material. SWNT devices may be especially suited for high power applications.

Figure 22  shows a flow diagram of a technique for fabricating a single-walled carbon nanotube diode device using chemical vapor deposition (CVD) synthesis.