boz.
if you're really concerned about Vitesse's technology and proprietary manufacturing processes, then you'd be well served to read the 10-k. i've taken the liberty of culling a section for you (see below). personally, i don't view this as an issue; however, i think it's worth noting that while the processes are proprietary, Vitesse very much uses industry standard fab equipment (like Applied Materials' metal- and chemical-vapor-deposition equipment).
furthermore, if you'd rather not see clemens get only the second post-season starting win of his illustrious career tonite, then you can take a gander at Vitesse's fascinating patents here:
enjoy, -chris.
164.195.100.11
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TECHNOLOGY The Company believes the limitations of silicon-based CMOS, BiCMOS, and ECL ICs have become more pronounced as the requirements of the telecommunications, data communications and ATE systems providers have increased. While CMOS offers certain complexity advantages over the alternative silicon processes, the Company believes it lacks the speed required for many high-performance systems. ECL technology offers higher speeds but at the cost of high power dissipation, which limits its use for high-complexity applications. BiCMOS offers higher performance than is obtainable from CMOS, but less than that offered by ECL, at levels of complexity which are greater than that available from ECL but lower than that provided by CMOS. BiCMOS is slower than ECL and, the Company believes, does not achieve the speed necessary for the highest performance telecommunications, data communications and ATE systems.
GaAs has inherent physical properties which allow electrons to move several times faster than within silicon. This higher electron mobility provides the Company with the flexibility to manufacture ICs that operate at much higher speeds than silicon devices or to operate at the same speeds with reduced power consumption. The following table compares the intrinsic transistor performance and cost per function for H-GaAs with alternative process technologies:
H-GaAs ECL BiCMOS CMOS -------- ------- -------- ------- Speed............... Highest High Moderate Lowest Power Dissipation... Low Highest Moderate Lowest Complexity.......... High Lowest Higher Highest Cost per Function... Moderate Highest Moderate Lowest
The Company employs proprietary H-GaAs process technology based on a refractory metal self-aligned gate ("SAG") process. SAG technology is universally used in the manufacture of complex silicon ICs. The process structure and logic implementation of the Company's GaAs ICs are similar to a traditional silicon MOS process with the exception that the gate metal is deposited directly on the GaAs substrate creating a metal-semiconductor junction comparable to depositing the metal on a thin oxide layer grown on the silicon substrate in the case of metal gate n-channel MOS.
The implementation of a SAG process in GaAs or silicon requires a gate metal structure that can withstand the high temperature of an ion implant activation anneal. This is in contrast to conventional microwave GaAs ("RF GaAs") process technologies which utilize a low temperature, non-self-aligned technology based on gold as the gate metal. The table below compares Vitesse's H-GaAs, traditional silicon MOS and microwave RF-GaAs:
Silicon Microwave H-GaAs MOS RF-GaAs -------- -------- --------- Self-Aligned... Yes Yes No Interconnect... Aluminum Aluminum Gold Complexity..... High Highest Medium
Another advantage of SAG technology in GaAs is the greater control over electrical transistor parameters compared to conventional gold gate technology. This control of the field effect transistor ("FET") characteristics has enabled the Company to be one of the few companies that have demonstrated the ability to manufacture products having lower power dissipation using direct coupled FET logic ("DCFL"). DCFL has the highest complexity, fewest elements per logic function and best available combination of speed at low power of any n-channel FET technology demonstrated in silicon or GaAs.
The use of a high-temperature process also allows Vitesse to use silicon industry standard aluminum interconnect technology. This enables the Company to utilize standard deposition and dry etch equipment for interconnects. The interconnect portion of the circuit represents a majority of mask levels in the manufacturing process.
The Company has significantly improved its process technology:
H-GaAs H-GaAs H-GaAs H-GaSs I II III IV ------ ------ ------ ------
Product Announcement Year............... 1986 1988 1991 1995 Gate Length............................. 1.2mum 0.8mum 0.6mum 0.4mum Metal Layers............................ 2 3 4 5 Maximum Relative Speed(1)............... 1.0x 1.4x 2.0x 3.0x Minimum Relative Power Dissipation(1)... 1.0x 0.7x 0.5x 0.3x
-------------(1) Compared to H-GaAs I.
The Company's H-GaAs IV 0.4 micron five-layer metal GaAs FET technology is capable of achieving higher complexity and lower power dissipation than previous Vitesse technologies. The Company manufactures various standard products as well as ASICs based on the GLX family of gate arrays and the SLX family of standard cell ICs. The GLX family of gate arrays has been designed to offer the same speed as the H-GaAs III family of gate arrays, but with lower power dissipation. This is intended to enable ICs to be packaged in a lower cost plastic package in the 100 MHz to 800 MHz range, thereby offering the customer a lower cost solution in this performance range.
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