What's the difference between 0.18um and 0.09um?

[johnq_hu]

technologie 0.09 um

I mean, unlike digital circuits, the minimal length is not always used in analog designs. If 1um is used for the device length, what's the difference for 0.18um and 0.09um process?:?:

 

[evilguy]

0.09 um tech

obviously the difference is vdd level. smaller voltage biasing should be used in 90nm to preserve headroom in order to remain all transistor in saturation.

 

[littlej_zju]

Threshold voltage is another concern. 90nm has lower Vth than 0.18um.

 

[ravet]

this a problem facing analog designers , which becomes a big challenge as technology shrinks for the sake of digital designs, in 0.18 technology ,nominal supply voltage is 1.8v, while in .09, supply is 1v , also, leakage problems becomes serious in .09 technology, and you may find a significant current passing in the gate , threshold voltage didnt shrink much to account for lower supply voltage and so , cascoding multi transistors will become veryy hard, also , designing analog circuits in this low supply will become very hard , for example , it will be a challenge to design a VCO to meet the required specs on phase noise within the required power budget

 

[johnq_hu]

So, process shrink doesn't mean area shrink for analog designs. Maybe the area will be larger in some cases. Now I am porting a amplifier from 0.18 to 0.09. I found I have to increase the device size to meet the output range requirment.