"Achieving radio frequency and microwave operation of both n-channel and p-channel transistors. By reaching this milestone, 3-inch POET wafers fabricated at BAE Systems (Nashua, NH) yielded submicron n-channel and micron-sized p-channel transistors operating at frequencies of 42 GHz and 3 GHz respectively. The team is aiming to optimize the operating frequencies to up to 300-350 GHz range for the n-channel device."

Hello Rogue,

Hopefully an electrical engineer can back me up on this, but my understanding is that you are confusing the definition of GHz. The mesure of Hertz can have multiple meanings in different context.

"radio frequency and microwave"

The GHz in this case applies to radio frequency and microwave, used in radar systems, in satellite communications, and as power amplifiers for cellular telephones.

These are not measures for PET Clock Rates.


https://en.wikipedia.org/wiki/Hertz

Vibration[edit]

Sound is a traveling longitudinal wave which is an oscillation of pressure. Humans perceive frequency of sound waves as pitch. Each musical note corresponds to a particular frequency which can be measured in hertz. An infant's ear is able to perceive frequencies ranging from 20 Hz to 20,000 Hz; the average adult human can hear sounds between 20 Hz and 16,000 Hz.[7] The range of ultrasound, high-intensity infrasound and other physical vibrations such as molecular vibrations extends into the megahertz range and well beyond.

Electromagnetic radiation[edit]

Electromagnetic radiation is often described by its frequency—the number of oscillations of the perpendicular electric and magnetic fields per second—expressed in hertz.

Radio frequency radiation is usually measured in kilohertz (kHz), megahertz (MHz), or gigahertz (GHz). Light is electromagnetic radiation that is even higher in frequency, and has frequencies in the range of tens (infrared) to thousands (ultraviolet) of terahertz. Electromagnetic radiation with frequencies in the low terahertz range, (intermediate between those of the highest normally usable radio frequencies and long-wave infrared light), is often called terahertz radiation. Even higher frequencies exist, such as that of gamma rays, which can be measured in exahertz. (For historical reasons, the frequencies of light and higher frequency electromagnetic radiation are more commonly specified in terms of their wavelengths or photon energies: for a more detailed treatment of this and the above frequency ranges, see electromagnetic spectrum.)

Computers[edit]

In computers, most central processing units (CPU) are labeled in terms of their clock rate expressed in megahertz or gigahertz (106 or 109 hertz, respectively). This number refers to the frequency of the CPU's master clock signal ("clock rate"). This signal is a square wave, which is an electrical voltage that switches between low and high values at regular intervals. Hertz has become the primary unit of measurement accepted by the general populace to determine the performance of a CPU, but many experts have criticized this approach, which they claim is an easily manipulable benchmark as some processors use multiple clock periods to perform a single operation, while others can perform multiple operations in a single cycle.[8] For home-based personal computers, CPU clock speeds have ranged from approximately 1 MHz in the late 1970s (Atari, Commodore, Apple computers) to up to 6 GHz in IBM POWER processors.

Various computer buses, such as the front-side bus connecting the CPU and northbridge, also operate at various frequencies in the megahertz range.


https://www.britannica.com/EBchecked/topic/289645/integrated-circuit-IC/236556/Memory-circuits

Radio-frequency ICs

Radio-frequency ICs (RFICs) are rapidly gaining importance in cellular telephones and pagers. RFICs are analog circuits that usually run in the frequency range of 900 MHz to 2.4 GHz (900 million hertz to 2.4 billion hertz). They are usually thought of as ASICs even though some may be configurable for several similar applications.

Most semiconductor circuits that operate above 500 MHz cause the electronic components and their connecting paths to interfere with each other in unusual ways. Engineers must use special design techniques to deal with the physics of high-frequency microelectronic interactions.

Microwave monolithic ICs

A special type of RFIC is known as a microwave monolithic IC (MMIC). These circuits run in the 2.4- to 20-GHz range, or microwave frequencies, and are used in radar systems, in satellite communications, and as power amplifiers for cellular telephones.

Just as sound travels faster through water than through air, electron velocity is different through each type of semiconductor material. Silicon offers too muchresistancefor microwave-frequency circuits, and so the compoundgallium arsenide(GaAs) is often used for MMICs. Unfortunately, GaAs is mechanically much less sound than silicon. It breaks easily, so GaAs wafers are usually much more expensive to build than silicon wafers.