Molecular beam epitaxial growth of III-V semiconductor ... - KOBRA

Theoretical Background of Semiconductor Nanostructures
Silicon transistors manufacturing technology has built on these advantages
and advances of fabrication tools to the point where the state of art fabrication
facilities can produce billions of transistors per wafer at the production rate of
thousands of wafer per day, like in the big microprocessor chip manufacturing
industry. Considering these huge and intense amount of investment which has
gone to Si transistor technology in the last decades and the domination of Si
transistor in modern semiconductor devices and equipments. It is expected that
Si will continue keep dominating the microelectronics industry for the foreseeable
future [13].
• Silicon Challenges :
The recent advances of semiconductor technology with increasing transistor
speed and density on Si wafers have started to expose some of the inherent limitations
of traditional Si circuits and chips for ultra-high speed and high-density
microelectronics applications (super chips) [13]. In particular, relatively low carrier
mobility compared to other semiconductor compounds like GaAs and InP
and the inability of Si crystals to form direct bandgap optoelectronic devices,
have both begun to restrict the speed and the rates at which Si-based integrated
circuits can operate. However, optical circuit interconnects oer an alternative
model for high-speed microelectronics. In which individual circuits or devices on
wafer chip are multiplexed by optical waveguides, providing crosstalk-free data
paths with exponentially higher data rates than current metal wires [13, 11].
The performance benets oered by optoelectronic integration on Si chips are in
essence and in the same importance of those oered by optical ber technology
that replaced much of traditional metal wiring in the telecommunications networks.
Individual ber optic waveguides capable of carrying trillions of bits of
digital data per second through hundreds of discrete channels, now carry mostly
all of the long-distance voice and data trac in the modern world [13]. Optoelectronic
interconnects promise revolutionary speed and bandwidth development for
Si integrated circuits if they can be successfully integrated in the current mature
Si transistor microelectronics platform, these transistors and optical intercon-
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