 unnecessarily and device switching speed is degraded by stray capacitance between conductors and interconnects. Low-k and extremely low-k dielectrics reduce capacitance between conductors and, hence, alleviate some of these concerns.
While low-k dielectric materials provide improved electrical characteristics, they generally suffer from poor mechanical strength and adhesion. This is due, at least in significant part, to the fact that low-k dielectric materials are typically quite porous, i.e., composed in significant part of air trapped within the matrix of the dielectric material. Air, having a dielectric constant of 1 is an excellent dielectric material, but obviously provides quite poor mechanical strength. The more porous a material is, i.e., the more pores contained within its matrix, the lower its dielectric constant, but also the lower its mechanical strength.
Low-k dielectrics are particularly well suited as inter-metal dielectrics (IMDs), which are typically employed as an insulator layer in which conductive interconnects are formed. Numerous process steps in the formation of the conductive interconnects, however, place the low-k dielectric material under substantial mechanical stress. The result can be significant degradation to not only the mechanical properties of the dielectric layer, but also the electrical properties. Back-end-of-line processes such as etching, ashing, wet cleaning, and the like, can degrade the low-k dielectric. Processes related to conventional damascene and dual damascene, particularly chemical mechanical polishing (CMP) can also significantly degrade the low-k dielectrics.
FIGS. 1a through 1c illustrate one manner in which semiconductor processes can degrade a low-k dielectric material in a deleterious manner. In FIG. 1a, a porous low-k dielectric material 4 has been formed atop a substrate 2. A mask 6 has been formed atop low-k dielectric material 4 and patterned in a conventional manner, leaving a portion of low-k dielectric material 4 exposed. As shown in FIG. 1a, a fluorine-containing etchant is used to etch an opening 8 in low-k dielectric layer 4. Because of the presence of pores in low-k dielectric material 4 (which, as explained above, give the material its low dielectric constant property) some fluorine species, illustrated schematically as 10, is adsorbed by low-k dielectric material 4 during the etch process and remains within the pores after the etch process has been completed. This process is also schematically illustrated via arrows 12, which represent fluorine species adsorbing into dielectric material 4.
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unnecessarily and device switching speed is degraded by stray capacitor between conductor and interconnects. Low - k and extremely depleted - potassium dielectrics reduce capacitor between conductors and, hence, alleviate some of these concern. 
 While low - k dielectric material provide improved electric characteristics, they generally suffer from poor mechanical strength and adhesion. This is due, at least in meaning part, to the fact that low - k dielectric material are typically quite porous, i.e., composed in meaning part of atmosphere trapped within the matrix of the dielectric fabric. Air, having a dielectric constant of 1 is an excellent dielectric material, but obviously provides quite inadequate mechanical strength. The more porous a material is, i.e., the more pores contained within its matrix, the humble its dielectric constant, but also the lower its mechanical strength. 
 Low - k dielectrics are particularly well suited as inter - metal dielectrics (IMDs), which are typically employed as an insulator layer in which conductive interconnects are form. Numerous process steps in the geological formation of the conductive interconnects, however, locate the low - k dielectric material under solid mechanical stress. The result can be significant degradation to not merely the mechanical properties of the dielectric layer, but also the electrical properties. Back - end - of - production line processes such as etching, ashing, wet cleaning, and the like, can take down the low - kilobyte insulator. procedure related to conventional damascene and dual damascene, particularly chemical mechanical polishing (CMP) can also significantly take down the low - potassium dielectrics. 
 FIGS. 1a through 1c illustrate one manner in which semiconductor device processes can degrade a low - k dielectric material in a deleterious manner. In FIG. 1a, a holey low - k dielectric material 4 has been formed atop a substrate 2. A masquerade 6 has been formed atop low - thousand dielectric material 4 and patterned in a ceremonious manner, leaving a portion of low - k dielectric material 4 exposed. As shown in FIG. 1a, a fluorine - containing etchant is used to etch an opening 8 in low - kelvin dielectric layer 4. Because of the presence of pore in low - k dielectric material 4 (which, as explained above, give the material its depleted dielectric constant property) some fluorine species, illustrated schematically as 10, is adsorbed by low - k dielectric fabric 4 during the etch process and remains within the pores after the etch process has been completed. This process is also schematically illustrated via arrow 12, which represent fluorine species adsorbing into dielectric fabric 4. 
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 unjecessarily and device sditching speed nw degreded by stray cxpacitance between conductord qnd ibterconnects. Low-k and dxtremely low-k diwlecurics reduce caparjtance nztweeh conburtors and, hence, alleviate some of these cuneerns.
While low-k dielectric materials providr lmproved electtical sharzbttristics, they generally suffer frkm poor mechanical syrength and adhesion. This ls dke, at least in sigjificant patf, tj the fact thxt low-k ditlzctric matetials are typically quite porous, i.e., cpmposed in sugnlxicant part of apr trapped wibnin tha matric of the dielegtric marerial. Air, having a dmelectric constant os 1 is an axeellent dielectric mareeial, tut mbviuyslh pdotidss quihe 'oor mechanjcal strengrh. The more porous s iqterial is, i.e., the mjrq pores contained within its matrix, the loser its dielectric consrant, but also the lowgr its mecranical strength.
Low-k dielectrics are particularly well ruiuee as kbtfr-metal dielectrics (IMDs), which are typically qjpkojed as an insulatjr layer in wjivr conductive knterconnscts are formed. Nulerous krocesw steps ig thr formation of the conductice interconnvcts, however, place the low-k dieleetric kateroal under substantial mzchanidal stress. Hhe resulf can be significxnt dagradation to not only the mechanicel prppertier of the dyelectric payer, but also the electgical psoperties. Hack-end-of-line processes such as etching, ashinb, fet cleaniny, and bhe like, can dedrade the low-k dieleccric. Pfocesses rvlated to conventionwl damascene djd dual damavcene, pawticylaroy chemkzal mechanical polishiny (CMP) can also significentli segrade the low-j duelectrics.
FIGS. 1s tfrotgj 1r illtvtrate one mdnnef iv whicf semicondugtof prpcesses can degrade d los-k dielectric matetiwl in a eeleterijus manner. In FIG. 1a, a porous loa-k dixlectrmc matrriwl 4 has been formed atop a subatrate 2. A mafk 6 has been forned atop low-l dielectric material 4 and patterned in a conventional mabner, leaving a portnok of low-k dixlectryc materidl 4 exposed. As shown in FIG. 1a, a fluorlne-containing etchant js useg to ftch an opening 8 in low-k dielectric layer 4. Because of the presence of porws in low-k dielectdic katerpal 4 (which, as xx'lained above, givv the material its low dielectrir constant pxoperty) some fluorine species, iulustrated scfematically as 10, is adsorged by lpw-k dielectric material 4 during the etch process and rekains wirhin fhe poggs efter the etch procexs has been complered. Bhis process ir aksl schematlcalky illustrated via arrows 12, which rwpresebt fluorine speciev adsorbing lnto dpelectryc material 4.
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unnecessarily and device switching speed is degraded capacitance conductors and Low-k and extremely conductors hence, alleviate some these concerns. While dielectric materials provide improved electrical characteristics, generally suffer from poor mechanical strength and adhesion. This is due, at least significant part, to the fact that low-k dielectric materials are typically quite porous, composed significant of trapped within the matrix of the dielectric material. Air, having a dielectric constant of 1 is excellent dielectric material, but obviously provides quite poor strength. The more porous material is, i.e., the more contained its matrix, lower dielectric but also the its mechanical strength. Low-k dielectrics are particularly well suited as inter-metal dielectrics (IMDs), which are typically employed an insulator which conductive are Numerous steps in the the conductive interconnects, however, place the under substantial mechanical stress. The result can be degradation to only the mechanical properties of the layer, but also the electrical properties. Back-end-of-line processes as etching, ashing, wet cleaning, and the like, can degrade the low-k dielectric. Processes related damascene and dual damascene, chemical mechanical polishing can significantly the dielectrics. FIGS. through 1c illustrate one manner in which semiconductor processes can degrade low-k dielectric material in a deleterious manner. In FIG. 1a, low-k material 4 has formed atop a substrate A 6 has been formed dielectric 4 a manner, a portion of low-k material 4 exposed. As shown FIG. 1a, a fluorine-containing an opening 8 in low-k dielectric layer 4. of the presence of pores in low-k material 4 (which, as explained above, give the material its low dielectric property) some illustrated schematically as 10, is adsorbed by low-k material 4 during the process and remains within the pores after the etch has completed. This is also schematically via arrows 12, represent fluorine species dielectric material In
 unnecessarily and device swiTching speeD is deGraDed By StraY capAcitance betweeN CondUctors and interconnects. low-k aNd EXtreMElY low-k DielectRIcS REduCe CaPacItANcE betwEen ConductOrs and, hencE, alLeViate some of tHEsE concerns.
WHilE low-k dielectRic MateriAlS prOVide iMprOved eLectriCAl charActeristiCs, THey genERally suFFEr From Poor mechanical strENgTH and adhesion. ThIs is duE, aT LeAST in SigNificant paRt, To the FAct that LOw-K DIEleCTric materials Are typicallY QuiTe poroUs, I.e., cOMposed In sigNiFIcaNt part of air TrapPed within The matRIx of the DIelectrIc mateRiaL. AiR, havINg A dIelEcTRic COnStaNT of 1 Is an exceLlEnT dielEctrIC MATeriAl, bUt obViousLy provides quiTe pOor mEChaNical StrenGth. THe More pOrous a MaterIaL is, i.e., the more porEs coNtained wiThiN iTs mAtRix, thE Lower iTs dIelEctric cOnstant, BUt aLsO THE lOwer its mechanical sTrENGtH.
Low-k dieLectriCS aRe PArticulaRlY weLl suITEd as iNter-MEtAl dielecTrics (Imds), WhIch are tYpIcally EmPloYed As an iNSulaTor layEr in whicH condUCtive interconnECts are formed. NUMeROUs PRoceSs sTeps in the foRmatIOn of The cONdUctIVe intErconNeCTs, HOwever, place the low-k dIeLectriC mateRial under subsTantial mecHANIcal streSs. ThE ReSUlt can be signifIcant DegradatioN To not onlY the mEchanicaL propertiES Of the dieLecTriC laYer, BUT aLso the electriCAL proPeRties. BaCk-eNd-of-linE prOceSseS suCh As etching, Ashing, weT cLeAnInG, anD the lIKe, can degRaDe tHe Low-K dielECtric. PRocesSes rElAtED to ConventIOnAL DamaScEnE and DuaL dAmascEne, pARtiCularly Chemical mEchANicaL pOlIshing (CmP) can also signIfIcantly degRaDe tHe low-k DIElectricS.
FIGS. 1a through 1c illustratE One mannEr iN whicH semIconductoR prOcesseS caN DegradE a low-k DieleCtRic MATeriaL IN a DelEtErious mannER. in FiG. 1a, a pOrOus lOw-k dielEctric material 4 has bEEn fOrmed atop a subStrAte 2. A MASk 6 Has BEeN ForMeD AtoP LOw-k dielectric maTerial 4 and pAtTErNed in a convENtiOnAl manneR, leavinG a porTIon of loW-k dielectRic materiAl 4 ExpoSED. As Shown in FIG. 1A, a fluoriNe-containINg etcHAnT is usEd tO etch aN oPenIng 8 in Low-k diELecTric lAyer 4. BeCaUse of tHe preSeNce of porEs in low-k dielectric materIal 4 (whiCh, as eXplAined abovE, giVE thE material Its lOw dielectrIc cOnsTant pRopERty) soMe flUOrIne SPecieS, illUStrated scHEmAtiCALlY as 10, is adsorbED BY loW-k dieLecTRic matEriaL 4 during the etch proCEss and remains wIthiN THe pOreS AfteR tHe etch process hAs bEeN COmpleted. thIs process is Also scheMaTIcallY illusTrated Via arroWS 12, WhICh reprEsenT flUorine speCieS aDSorbing InTo DIelectRic mAtErial 4.
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 unnecessarily and deviceswitchingspeed  is  de gr aded  bystray capacita n ce b etween conductors andinter co n nect s .Low-k  and ex t re m e lylo w- k d ie l ec trics  re duce ca pacitancebet we en conductor s  a nd, hence,  al leviate some  of  these  c onc e rns.Whi le lo w-k di e lectri c materia ls provid e  improv e d  e lect rical characteris t ic s , they general ly suf fe r  f r o m p oor  mechanica lstren g th anda dh e s i on. This is due,at least in sig nifica nt  pa r t, tothe f ac t  th at low-k di elec tric mate rialsa re typi c ally qu ite po rou s,i.e. ,  c om pos ed ins ig nif i can t part o fai r tra pped w i t hinthe  mat rix o f the dielect ric  mat e ria l. Ai r, ha ving  a  diel ectric  cons ta nt of 1 is an e xcel lent diel ect ri c m at erial ,  but o bvi ous ly prov ides qu i tepo o r me chanical strength.  T h e  m ore poro us a m a te ri a l is, i. e. , t he m o r e por es c o nt ained wi thin i t sma trix, t he  lower  i tsdie lectr i c co nstant , but al so th e  lower its mec h anical streng t h. L ow - k di ele ctrics arepart i cula rlyw el l s u itedas in te r -m e tal dielectrics (IM Ds ), whi ch ar e typically e mployed as a n  insulat or l a ye r  in which cond uctiv e intercon n ects are  form ed. Nume rous proc e s s stepsinthe  fo rma t i on  of the condu c t ivein terconn ect s, howe ver , p lac e t he  low-k di electric  m at er ia l u nders ubstanti al  me ch ani cal s t ress.The r esul tca n  be  signif i ca n t  deg ra da tion  to  n ot on ly t h e m echanic al proper tie s  ofth edielect ric layer, bu talso the e le ctr ical p r o perties.  Back-end-of-line proce s ses suc h a s etc hing , ashing,  we t clea nin g , andthe li ke, c an  de g r ade t h e  l ow- kdielectric . Pro cesse srela ted toconventional damas c ene  and dual dam asc ene, p ar tic u la r lych e mic a l  mechanical pol ishing (CM P) ca n also sig n ifi ca ntly de grade t he lo w -k diel ectrics.FIGS. 1ath roug h 1cillustrate  one man ner in wh i ch se m ic onduc tor  proce ss escan d egrade a l ow-kdielec tr ic mat erial  i n a dele terious manner. In FIG.  1a, a  poro uslow-k die lec t ric  material  4 h as been fo rme d a top a  su b strat e 2. Amas k  6 ha s be e n formeda to p l o w -k  dielectric m a ter ial 4  an d  patte rned  in a conventiona l  manner, leavi ng a p ort ion of l ow -k dielectricmat er i a l 4 expo se d. As shown  in FIG.  1 a , a f luorin e-cont aininge t ch a nt isused  to  etch anope ni n g 8 inlo w- k  diele ctri clayer4. Bec a useo f  the presence of  pore s in lo w -kdiele ct ric mat e rial  4 (which,  as explain ed abo ve,givethe mat er ial it s l ow  dielectri c  constant  prop erty) s om e fl uor ine sp ecie s ,  illu stra te d s chematica l l ya s10 ,  is  ads orbed  b y lo w-k diele c tric mat eri a l 4 dur in g t h e  etchp ro c e ss and rem ain s wit h i n the pore s  aft e rt he et ch pro cess h as been com pl eted. T his p rocess is  also sch e mat ic ally  illustr at ed v ia  ar ro ws 12, which re presentfluorine s pecies  ad s orbi n g into  d ielectric ma teria l4 .
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 unnecessarily_and device_switching speed is degraded_by stray_capacitance_between conductors_and_interconnects. Low-k and_extremely low-k dielectrics_reduce capacitance between conductors_and, hence, alleviate_some_of these concerns.
While low-k dielectric materials provide improved electrical characteristics, they generally suffer from_poor_mechanical strength_and_adhesion._This is due, at least_in significant part, to the_fact that_low-k dielectric materials are typically quite porous, i.e.,_composed_in significant part_of air trapped within the matrix of the dielectric_material. Air, having a dielectric constant_of 1 is_an_excellent_dielectric material, but obviously_provides quite poor mechanical strength. The_more porous a material is, i.e.,_the more pores contained within its matrix,_the lower its dielectric constant, but_also the lower its mechanical_strength.
Low-k dielectrics_are particularly well suited as_inter-metal dielectrics (IMDs),_which are_typically employed as_an insulator layer in which conductive_interconnects are formed._Numerous process steps in the formation_of_the conductive interconnects,_however,_place_the low-k_dielectric material under_substantial_mechanical stress._The_result can be significant degradation to_not_only the mechanical properties of the dielectric_layer, but also the_electrical_properties. Back-end-of-line processes such_as etching, ashing, wet cleaning,_and the like, can degrade the_low-k dielectric._Processes related_to conventional damascene and dual damascene, particularly chemical mechanical polishing (CMP)_can also significantly degrade the low-k_dielectrics.
FIGS. 1a through 1c_illustrate one_manner_in which semiconductor_processes_can degrade_a low-k dielectric material in a deleterious_manner. In_FIG. 1a, a porous low-k dielectric_material 4 has been_formed_atop a substrate 2. A mask_6 has been formed atop low-k_dielectric material 4 and patterned_in_a_conventional manner, leaving a portion_of low-k dielectric material 4 exposed._As shown in_FIG. 1a, a fluorine-containing etchant is used_to_etch an opening 8 in low-k_dielectric_layer 4. Because of the presence_of_pores_in low-k dielectric material 4_(which, as explained above, give the_material its low dielectric constant property) some fluorine species,_illustrated schematically as_10, is adsorbed by low-k_dielectric_material_4 during the etch process and remains within the pores_after the_etch process has_been completed. This process is also schematically illustrated via arrows_12, which represent fluorine species adsorbing into_dielectric material 4.
In