Slides: CMOS Basics.

Transcription

1 MO Basics ysem-on-hi oluions & Archiecures Technische Universiä München Module ouline Inroducion o MO Where is MO? Wha is MO? Why is MO so aracive? How does MO work? Basics MO evice Basics aic MO Logic equenial Logic MO and FM design Power onsumion Of aic MO Logic o - MO Basics -

2 P P OA Where is MO? RAM AI µp FPGA o - MO Basics - 3 Where is MO? RAM AI µp FPGA There! o - MO Basics - 4

3 Where is MO? Garner: World-wide semiconducor revenue 00: 155 B U o - MO Basics - 5 Where isn MO? ige / GaAs ulra high seed BiMO mixed-signal high seed Biolar Analog wireless ower amlifiers recievers very high seed digial communicaions inerface elecronics mm-wave defense o - MO Basics - 6

4 MO - Wha is i? nmo MO dd n+ + n Meal (Poly-i) Oxide (io) emiconducor The hannel ye gives he refix of he ransisor o - MO Basics - 7 The in MO signals he combinaion of - and n-mofet omlemenary Why MO? Elecrical Reasons Low ower dissiaion Noise immuniy lean logic levels One suly volage ascadable io -Layer i-wafer Phoolihograhic Mask Phooresis Poly-i-Layer Eching Lihograhy Ligh Ligh aerns Phooresis Economical Reasons Easy o design Fabricaion well undersood Highly inegraeable Process oing Aoms (P or As) eosiion o - MO Basics - 8

5 How does i work? 0 - dd dd n+ + inversion dd 0 dd n+ + inversion o - MO Basics - 9 How does i work? ource () 0 gs gs ds ds =cons. 0 o - MO Basics - 10

6 How does i work? gs(1)=cons. ource () 0 gs ()=cons. gs gs - ds ds ds = gs (1)- 0 ds = gs ()- o - MO Basics - 11 How does i work? gs(1)=cons. ource () 0 gs ()=cons. gs gs () gs (1) gs - ds ds ds = gs (1)- ds = gs ()- 0 ds > gs ()- o - MO Basics - 1

7 Linear Region ource () gs x x+dx L (x) dq ds Only valid before inch-off! o - MO Basics - 13 Linear Region rain curren: 1) = ρ x v = dq v / dx Induced harge/area: ) dq = d ( gs - n - (x) ) ifferenial aaciance: 3) d / dx = G / L arrier seed: 4) v = - µ d/dx Boundary condiions: (0) =0 and (L) = ds I n L G o - MO Basics - 14

8 MOFET Basics nmo MO chemaic ymbols Gae Gae ource rain onnecions rain ource Bulk/ubsrae - () ubsrae level usually goes o (omied from now on) ubsraes are isolaed. o - MO Basics - 15 Bulk/ubsrae + ( ) MOFET olages And rain urren nmo G ecor onvenions* G MO On lower oenial ource is always On higher oenial 0 Gae-ource olage rain-ource olage rain urren 0 *Please avoid G,, G, G o - MO Basics - 16

9 MOFET Inu haracerisics G cons. 0 I G cons. 0 n off conducing conducing off o - MO Basics - 17 MOFET Ouu haracerisics cons. n G G cons. I n linear sauraion sauraion linear o - MO Basics - 18

10 MOFET Model Equaions (ah) I n ( off ) ( linear) ( sauraion) real ah n n o - MO Basics - 19 MOFET Model Equaions (ah) 0 0 ( off ) I 0 ( linear) ( sauraion) ah I real o - MO Basics - 0

11 imensioning w Ox L min W Transconducance: K L esigner s Parameer: W onflicing esign Goals: Area => W=L min eed => high W, l=l min => always use L min for digial circuis where o - MO Basics - 1 Ox 0 K Ox Technology Parameers Mobiliy µ n = x µ esigner uses W o comensae for lower curren drive of MOFET Minimum Feaure ize: L min Oxide dielecric/hickness: ε ox, ox Module ouline Overview MO evice Basics aic MO Logic Inverer Logic Gaes Arihmeic in MO equenial Logic MO and FM design Power onsumion Of aic MO Logic o - MO Basics -

12 aic MO Inverer P I A Z A n N n Z A Z 0 1 o - MO Basics aic olage Transfer urve (T) Z off on on off N P I P A n N n Z I n - h A A Z o - MO Basics - 4

13 T: Logic Levels 0 / 1 Z off on on off N P I P A n N n Z n - h A A Z o - MO Basics - 5 ynamic Behaviour A 50% Z 50% I HL LH Proagaion delay from inu o ouu No infiniely see sloes a inu aaciive Load a he ouu needs o be (dis)charged 50% ignal level marks serve as measure hooks Tyical Inverer (65 nm) delay as of oday: 4 s o - MO Basics - 6

14 Effec of Inu loe on Inv. elay A 90% dd - 10% HL P sill off (Z sill low) P on (Z rising) Transiion ime of a signal: Time elased beween 10% and 90% of swing Effec on delay: For a falling (rising) inu signal, no ouu rise (fall) can occur before P (N) swiches o on => LH n => HL HL LH o - MO Basics - 7 Effec of aaciance on Inv. elay riving gae Oher wire wire riven gae(s) A A Lumed caaciance 0.13µ: 3-6 ff Z Lumed aciance: Inu (gae) caaciies of nex logic gaes + rain caaciies + Wire caaciies o - MO Basics - 8

15 Effec of aaciance on Inv. elay gs I d ds dd A For a firs order analysis we assume he inu sloe o be infiniely see A I Z Lumed caaciance 50% Z gs =- dd LH =f()=? gs - ds gs and ha we oerae he FET in is linear region o - MO Basics - 9 Effec of aaciance on Inv. elay dd R on, A Z = R on,n Inverer model: on: Resisance off: oen swich oeraing in linear region of ah 50% o - MO Basics - 30

16 Effec of aaciance on Inv. elay dd R on, A Z LH =f()=? R on,n Inverer model: on: Resisance off: oen swich oeraing in linear region of ah 50% o - MO Basics - 31 Effec of aaciance on Inv. elay erivaion : 1) Kirchhoff for currens: ) aacior formula: 3) W s law: 4) Kirchhoff for volages: 5) Resolve by : 6) ome mah: 0.5dd 0 0 ds dd R R I d I I Ron, dd d on, on, Ron, R on, 1 ln dd o - MO Basics - 3

17 Effec of aaciance on Inv. elay LH R, ln on 1 ah real simle R on, I d R on, I for d 1 o - MO Basics - 33 iscussion LH load Increase of aaciive Load Oxide hickness hannel lengh abs. hreshold volage Ox L W... Ox dd Mobiliy hannel widh relaive oxide (=k) uly olage => Proagaion delay increase o - MO Basics - 34 =>Proagaion delay decrease

18 imensioning II The hreshold volage is an imoran arameer. I s value mus be carefully seleced, by echnology facors: hannel oing Oxide hickness a design ime: choosing a echnology ha suors mulile (wo) hreshold volages by inroducing a subsrae volage a run ime: by adoing he subsrae volage o design condiions bulk hannel doing o - MO Basics - 35 imle aic MO Logic Gaes NOR A B Z A B Z A B Z A B Z NAN NOR Z A B Z NAN o - MO Basics

19 Generic Model of aic MO A1... An Z NAN NOR o - MO Basics - 37 Why no like his? n A B OR? rain ource Z ource rain MOFET Inu haracerisic ondiion for MOFET o build u conducing channel: gs > In figure on he lef: nmo ulls u Z o n ( bad ull u ) MO ulls down Z o (bad ull down ) Problemaic signal levels for nex logic sage o - MO Basics - 38

20 ysemaic aic MO Logic esign Examle Funcion: Z=AB+ MO always invers => add exra inverer: Z=AB+ A B ar a he ouu and find a way hrough n- MOFET o ground: serial for AN (AB) arallel for OR () raw he way o dd by using he dual n-nework and -MOFET If everyhing is done righ, here will never be a conducing ah beween dd and. o - MO Basics - 39 A B Z References [1] R. J. Baker e al., MO circui design, layou, and simulaion, IEEE Press, IBN [] N. H. E. Wese e al., Princiles of MO Lesign, Addison Wesley, IBN [3] IA, Inernaional Technology Roadma for emiconducors, h://ublic.irs.ne/ Picure credis: www-im.unine.ch, allserv.rug.ac.be o - MO Basics - 40

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