90 nanometer

From ArticleWorld

90 nanometre (90 nm) processes in semiconductor fabrication refer to the technology involving average feature sizes up to 90 nanometres with minimum feature sizes being as less as 45 nanometres. 90 nanometre processes had been popular in the semiconductor fabrication industries from 2002 and till 2004.

Early development

Industries using 90 nanometre technology have seen several breakthroughs. These include FPGA, network chip, DSP and flash memory fabrication. Among the companies involved in 90 nm manufacturing – but using different techniques – include Intel, IBM, Texas Instruments and Motorola.

The industrial standard before the 90 nm process came into being was the 130 nm process. The next projected milestone is the 65 nm process, which is already being used by Intel in its Pentium Extreme Edition 995. Greatly reduced sizes in semiconductor fabrication mean larger amount of space made available and smaller or narrower processor gates. Narrower gates mean quicker switching between on and off states. Due to wire delay, however, faster transistor speeds do not necessarily imply faster clock speeds for chips.

Drawbacks

Reduced nanometre-size processes come with a few disadvantages as well. Electromagnetic interference, accidental interconnects and unwanted capacitances are a major problem. Leakage is also a problem. Leakage is a phenomenon in which electrons tunnel through an insulating region. It increases with an increase in the thickness of the insulating region. This leads to higher power consumption and complete circuit failure.

In a process called ‘strained silicon fabrication’ a layer of silicon (with silicon atoms stretched beyond their normal inter-atomic distances) is deployed along with a low-dielectric-constant insulator. To overcome leakage, manufactures apply a thin layer of oxide to the silicon wafer, to prevent electrons from ‘leaping’ wires.