
dopping (ardhachaalaka)

ardhachaalaka ulppaadanathil, oru aantharika ardhachaalakathilekku athinte vaidyutha, opttikkal, gadanaaparamaaya gunangal modulate cheiyunnathinaayi maalinyangal manahpoorvvam avatharippikkunnathaan dopping. dopp cheytha metteeriyaline extrinsic semikandaktar ennu vilikkunnu. 
cheria ennam dopant aattangalkk vaidyuthi vahikkaanulla ardhachaalakathinte kazhivine maattaan kazhiyum. 100 dasalaksham aattangalil oru dopant aattam cherkkumbol, dopping "loow" allengil "laitt" aanennu parayappedunnu. pathinayiram aattangalil onninte kramatthil kooduthal dopant attangal cherkkumbol, doppingine "uyarnna" allengil "kanatha" ennu vilikkunnu. ithu palappozhum enn-type doppingin "enn +" allengil pii-type doppingin "pii +" ennu kaanikkunnu. (dopping samvidaanathekkurichulla kooduthal vishadamaaya vivaranathinu ardhachaalakangalekkurichu lekhanam kaanuka.") ardhachaalakathekkaal oru chaalakaneppole pravartthikkunna oru ardhachaalakathe degenerate ardhachaalakamaayi vilikkunnu. oru ardhachaalakathe p, n ennivayude thulya alavil dopp cheythittundenkil athine i-type ardhachaalakamaayi kanakkakkaam.
phosphorukaludeyum sinttilettarukaludeyum pashchaathalatthil, dopping aaktiveshan ennaanu ariyappedunnathu; ithu ardhachaalakangalile dopant aaktiveshan aayi thettidharikkaruthu. chila pigmentukalile niram niyantrikkaanum dopping upayogikkunnu.
charithram.
ardhachaalakangalile (dopping) maalinyangalude phalangal kristtal radio dittaktarukal, selenium rectifierukal thudangiya upakaranagalil anubhavaparamayi valarekkaalamaayi ariyappettirunnu. udaaharanathinu, 1885-ll shelford bidwell 1930-ll jarmman shaasthranjanaaya bernhard gooden oororutharum ardhachaalakangalude gunangal avayil adangiyirikkunna maalinyangal moolamaanennu swathanthramaayi report cheythu. 
randaam lokamahaayudhasamayathu sperry gyroscope kambaniyil jolie cheythirunna joonn roobert wood yard aanu dopping prakriya aupachaarikamaayi vikasippichath. dopping enna vaakk athil upayogichittillengilum, 1950 ll purappeduvicha addehathinte us pettant aavarthanappattikayile naitrajan nirayil ninnu jermeniyathilekku cheria alavil khara moolakangal cherthu thiruthal upakaranangal nirmmikkunnathinulla reethikal vivarikkunnu. radaarile addehathinte pravartthanatthinte aavasyangal ardhachaalaka uthejakathekkurichulla kooduthal gaveshanam nadathunnathil ninnu marathottatthe thadanju.
bell laabukalilum samanamaaya pravartthanangal gorden keey nadatthi. 1953ll yuu. ezz pettant nalkia teal, morgan theepporikal.
wood yaardinte muun pettant sperry raandinte vipulamaaya vyavahaarathinte adisthaanamaanennu thelinju.
carrier eakaagratha.
upayogicha dopantinte saandrata pala vaidyutha gunangaleyum badhikkunnu. metteeriyalinte charge carrier saandrathayaanu ettavum pradhanam. taapa santhulithaavasthaykku keezhilulla oru aantharika ardhachaalakathil, electronukaludeyum dwaarangaludeyum saandrata thulyamaanu. athaayath,
taapa santhulithaavasthaykku keezhilulla oru aantharikamallaatha ardhachaalakathil, bandham (kuranja doppingin) aayi maarunnu
ivide "n" 0 ennathu electronukalude saandrathayaanu, "p" 0 ennathu chaalaka dwara saandrathayaanu, "ni" ennathu vasthuvinte aantharika vaahakamoolamaanu. aantharika vaahaka saandrata vasthukkalkkidayil vyathyaasappedunnu, ithu thapanilaye aasrayichirikkunnu. udaaharanathinu, silikkaninte "nii" ekadesham 1.08 × 1010 centimeter −3 aanu, 300 kelvinukalil, ekadesham muriyile thaapanila.
pothuve, vardhicha uttejaka marunnu vaahakarude uyarnna saandrata kaaranam vardhicha chaalakathayilekku nayikkunnu. degenerate (valare uyarnna dopp cheytha) ardhachaalakangalkku lohangalumaayi thaarathamyappeduthaavunna chaalakathayude alavu undu, avaa palappozhum lohathinu pakaramaayi integrated sarcuteukalil upayogikkunnu. ardhachaalakangalile aapekshika dopping saandrathaye soochippikkaan palappozhum superscript plus, mainus chinnangal upayogikkunnu. udaaharanathinu, "n" + ennathu uyarnnathum palappozhum degenerate cheyyappettathum uttejaka saandrathayullathumaaya oru n-type ardhachaalakathe soochippikkunnu. athupole, "p"-valare laghuvaayi dopp cheytha p-type metteeriyaline soochippikkum. doppinginte degenerate levelukal polum bays semikandaktarumaayi bandhappett maalinyangalude kuranja saandrathaye soochippikkunnu. aantharika kristalin silikkanil ekadesham 5x1022 attangal/sem. mee. 3 undu. silikkan ardhachaalakangalude uttejaka saandrata 1013 sem. mee. −3 muthal 1018 sem. mee. −3 vare aakam. ekadesham 1018 sem. mee. −3 nuu mukalilulla uttejaka saandrata muriyile thapanilayil degenerate aayi kanakkaakkappedunnu. degenerally dopp cheytha silikkanil aayirathil bhaagangalude kramatthil silikkanumayulla ashudhiyude anupatham adangiyirikkunnu. eee anupatham valare cheruthaayi dopp cheytha silikkanil oru bilyanil bhagangalaayi kuraykkaam. saadhaarana saandrata moolyangal eee shreniyil evideyengilum veezhunnu, avaa ardhachaalakathinaayi uddeshichittulla upakaranathil aavasyamulla gunangal uthppaadippikkunnathin anuyojyamaanu.
baand ghadanayil swaadheenam.
oru nalla christalil oru ardhachaalakathe dopping cheiyunnathu baand vidavinullil anuvadaneeyamaaya oorjja avasthakal avatharippikkunnu, pakshe dopant tharavumayi poruthappedunna oorjja bandinode valare aduthaanu. mattoru vidhathil paranjaal, electron daathaakkalude maalinyangal kandakshan baandinu sameepam avasthakal srishtikkumbol electron sweekarikkunna maalinyangal valence baandinu sameepam avasthakal srishtikkunnu. eee oorjjaavasthakalum ettavum aduthulla oorjja band thammilulla vidavu saadhaaranayaayi dopant-saitt bonting energy allengil "ibu" ennu vilikkappedunnu, ithu thaarathamyena cheruthaanu. udaaharanathinu, silikkaninte baand gapp ekadesham 1.12 ivi aayi thaarathamyappeduthumbol silikkan balkkile boroninte "ibu" 0.045 ivi aanu. ibu" valare cheruthaanu ennathinaal, muriyile thaapanila praayogikamaayi ellah dopant aattangaleyum taapa ionise cheyyaanum chaalanatthilo valence baandukalilo free charge carrierukal srishtikkaanum paryaapthamaan.
fermi levalumaayi thaarathamyappeduthumbol oorjja baandukal maattunnathil dopantukalkk pradhana swaadheenamundu. ettavum kooduthal saandrathayulla dopantumaayi poruthappedunna energy baand fermi levelinode adukkunnu. thermodynamic santhulithaavasthayilulla oru sisttathil fermi level sthiramaayi thudaranamennathinaal, interfaceukal mathiyaya reethiyil vrithiyaakkaan kazhiyumenkil, vyathyastha gunangalulla vasthukkalude paalikal adukkunnathu baand valayunnathiloode prachodippikkappedunna niravadhi upayogapradamaaya vaidyutha gunangalilekku nayikkunnu. udaaharanathinu, pii-type, enn-type metteeriyal ennivayude sanbarkka pradeshangalil baandukale varivariyayi nirthendathinte falamaayi sambhavikkunna baand valayalaanu pn jangshante savisheshathakal.
eee prabhavam oru baand diagramil kaanikkunnu. baand diagram saadhaaranayaayi valence bandileyum kandakshan baand arikukalileyum chila speshyal alavukalileyum vyathiyaanathe soochippikkunnu, palappozhum "x" ennu soochippikkunnu. saadhaaranayaayi rekhaachithrathil fermi level soochippikkunnu. chilappol doppinginte abhaavathil fermi levalaaya "intrinsic fermi level", "aii" kaanikkunnu. palatharam ardhachaalaka upakaranangalude pravartthanam vishadeekarikkunnathinu eee rekhaachitrangal upayogapradamaanu.
carrier saandrathayumaayulla bandham (kuranja uttejaka marunnu).
kuranja thothilulla doppingin, prasakthamaaya oorjjaavasthakal electronukal (kandakshan baand) allengil dwaarangal (valence baand) kondu viralamaayi janasamkhyayullavayaanu. poolii ozhivakkal avaganichukondu (maiks well-boltsman sthithivivarakkanakkukal vazhi) electron, hole carrier saandrathaykkaayi lalithamaaya padaprayogangal ezhuthaan kazhiyum
fermi level evideyaanu, kandakshan baandinte ettavum kuranja oorjjamaanu, ithu valence baandinte paramavadhi oorjjamaanu. iva aantharika saandrathayude moolyavumaayi bandhappettirikkunnu
dopping thalatthil ninnu swathanthramaaya oru padaprayogam, kaaranam (baand gapp) dopinginoppam marunnilla.
eakaagratha gadakangal nalkunnu
thapanilayil ekadesham sthirathayulla alavukalaaya electronukaludeyum dwaarangaludeyum phalapradamaaya pindangalude saandrata evideyaanu, avaa evideyaanu.
doppinginteyum sinthasisinteyum saankethikavidyakal.
kristtal valarchayude samayat dopping.
oro vepharinum eathaandu oru ekeekritha prarambha dopping nalkunna (saadhaaranayaayi silikkan) booal schokralsky reethiyiloode valarthunnathinaal chila dopantukal cherkkunnu. 
pakaramaayi, ardhachaalaka upakaranangalude samanvayathil neeravi-ghatta epitaxy upayogam ulppettekkaam. neeravi-ghatta epithaaxiyil, dopant mungamiyullah oru vaathakam reactorilekku avatharippikkan kazhiyum. udaaharanathinu, gallium arsenide enn-type gyaas doppinginte kaaryatthil, hydrajan sulfide cherkkukayum sulfur ghadanayil ulppeduthukayum cheiyunnu. uparithalathil sulferinte sthiramaaya saandrathayaanu eee prakriyayude savisheshatha. pothuve ardhachaalakangalude kaaryatthil, aavasyamulla electronic gunangal labhikkunnathin vepharinte valare nerttha paali maathrame dopp cheyyendathulloo.
valarchaykku sheshamulla dopping.
surcuted gadakangale nirvachikkunnathin, thiranjeduttha pradeshangal-saadhaaranayaayi photolithography niyanthrikkunnu-defusion, ayoon implaanteshan thudangiya prakriyakalaal kooduthal kuthivaykkunnu, randaamathe reethi vardhicha niyantranakshamatha kaaranam valia ulppaadana pravarthanangalil kooduthal janapriyamaan.
nyootron transmulation dopping.
prathyeka prayogangalkkulla asaadhaaranamaaya oru uttejaka reethiyaanu nyootron transmulation dopping (enn. tii. dii). hye-power electronics, semikandaktar dittaktarukalil silikkan enn-type dopp cheyyaan ithu saadhaaranayaayi upayogikkunnu. nyootron agiranam cheiyunnathiloode sii-30 isotope phoosphoorus aattamaakki parivartthanam cheiyunnathine ithu adisthaanamaakkiyullathaanu
soothravaakyam _ 6 
praayogikamaayi, neutronukal sweekarikkunnathinaayi silikkan saadhaaranayaayi oru nuclear reactorinu sameepam sthaapikkunnu. neutronukal silikkaniloode kadannupokunnathu thudarunnathinaal, kooduthal kooduthal phoosphoorus attangal parivartthanatthiloode uthppaadippikkappedunnu, athinaal dopping kooduthal kooduthal shakthamayi enn-type aayi maarunnu. defusion allengil ayoon implaanteshanekkaal valare kuranja dopping reethiyaanu enn. tii. dii., ennaal valare ekeekrithamaaya dopant vitharanam srishtikkunnathinte gunamundu.
dopant gadakangal.
group IV ardhachaalakangal.
group IV ardhachaalakangalaaya diamond, silikkan, germanium, silikkan carbide, silikkan-germanium ennivayil ettavum saadhaaranamaaya dopantukal group III-ll ninnulla sweekarthaakkalaanu allengil group V moolakangalil ninnulla daathaakkalaanu. silikkan uthejippikkaan boron, arsenic, phoosphoorus, idaykkide gallium enniva upayogikkunnu. silikkan integrated surcuted ulppaadanathinu thiranjedukkunna pii-type dopaantaan boron, kaaranam ithu junction aazham eluppathil niyanthrikkaavunna nirakkil vyaapikkunnu. silikkan vepharukalude bulk dopinginaayi phoosphoorus saadhaaranayaayi upayogikkunnu, athesamayam jangshanukal vyaapippikkaan arsenic upayogikkunnu, kaaranam ithu phosphorasinekkaal saavadhaanathil vyaapikkukayum athinaal kooduthal niyanthrikkaavukayum cheiyunnu.
phoosphoorus polulla group vii moolakangalumayi shudha silikkan dopp cheiyunnathiloode, vyakthigatha aattangalil ninnu paridhiyillaathathum samyukthathe vaidyuthachaalanaathmakamaaya enn-type ardhachaalakamaakkaan anuvadikkunnathumaaya adhika valence electronukal cherkkunnu. naalam valence electron illaathaaya group III moolakangalumayi dopping cheiyunnathu, chalikkaan kazhiyunna silikkan laattisil "takarnna bondukal" (dwaarangal) srishtikkunnu. athinte phalam vaidyuthachaalanaathmakamaaya pii-type ardhachaalakamaanu. eee pashchaathalatthil, oru group vii ghadakam oru electron daathaavaayum group III ghadakam oru sweekarthaavaayum perumaarunnuvenn parayappedunnu. oru diodinte bhauthikashaasthrathile oru pradhana aashayamaanith.
valare kanatha dopp cheytha ardhachaalakan oru nalla chaalakane (loham) poleyaanu perumaarunnath, athinaal kooduthal rekheeya positteev taapa gunakam pradarshippikkunnu. atharam prabhavam sensistarukalil udaaharanathinu upayogikkunnu. mattu tharatthilulla (enn. tii. sii allengil pii. tii. sii) thermistarukalil kuranja alavil uttejaka marunnu upayogikkunnu.
mattu ardhachaalakangal.
thaazhepparayunna pattikayil "(x-nuu pakaram vaykkunnathu)" ennathu paranja paranthasissinu munbulla ellah vasthukkaleyum soochippikkunnu.
nashtapariharam.
mikka kesukalilum thathfalamaayundaakunna dopped ardhachaalakathil pala tharatthilulla maalinyangal undaakum. ardhachaalakathil thulya ennam daathaakkalum sweekarthaakkalum undengil, aadyathethu nalkunna adhika coor electronukal randaamathethu moolamulla takarnna bondukale thripthippeduthaan upayogikkum, angane dopping rund tharatthilumulla swatantra vahakareyum ulppaadippikkunnilla. eee prathibhasam "compensation" ennariyappedunnu, ithu bhooribhaagam ardhachaalaka upakaranagalilum pn junctionil sambhavikkunnu. 
daathaakkalude ennam sweekarthaakkalekkaal kooduthalo thiricho aaya bhagika nashtapariharam, upakarana nirmmaathaakkale oru bulk ardhachaalakathinte uparithalathinu thaazheyulla oru prathyeka paaliyude tharam aavarthichu vipareethamaakkaano (vipareethamaakkaano) counterdoping ennu vilikkappedunna uyarnna doppantukal thudarchayaayi vyaapikkukayo sthaapikkukayo cheyyaan anuvadikkunnu. bulk silikkaninte uparithalathinu keezhil aavashyamaaya pii, enn tharam pradeshangal srishtikkunnathinu thudarchayaayi thiranjeduttha counterdoping ghattangaliloodeyaanu mikka aadhunika ardhachaalaka upakaranangalum nirmmikkunnath. epitaxy vazhi atharam paalikal thudarchayaayi valarthunnathinulla oru badalaanith.
daathaakkaludeyo sweekarthaakkaludeyo ennam vardhippikkunnathino kuraykkunnathino nashtapariharam upayogikkaamenkilum, daathaavinteyum sweekarthaakkaludeyum ayonukalude thuka chalanathe baadikkunnathinaal electron, hole chalanathmakatha ellaayppozhum nashtaparihaaratthiloode kuraykkunnu.
chaalaka polymerukalil dopping.
ookseekaranam varuthunnathino chilappol kuraykkunnathino raasapravarthanangal cherkkunnathiloode chaalaka polymerukal kuthivaykkaam, angane electronukal ithinakam thanne saadhyathayulla chaalaka samvidaanathinullile chaalaka bhramanapathangalilekku thallappedunnu. oru chaalaka polymer dopping cheiyunnathinu rund praadhamika reethikalundu, iva randum ooksideshan-reduction upayogikkunnu (i.iii., redox) prakriya.
bhoomiyude anthareeksham ooksijan sambushtamaayathinaal enn-dopping valare kuravaanu, angane ooksidaising anthareeksham srishtikkunnu. electron sambushtamaaya, enn-dopped polymer "dii-dopp" (i.iii.polymer) neutral avasthayilekku reexidise cheiyunnu. athinaal, kemikkal enn-dopping nishkriya vaathakathinte anthareekshathil nadatthanam (udha.jii., aargon). vaidyutha raasa enn-dopping gaveshanathil valare saadhaaranamaanu, kaaranam seal cheytha flaskil oru laayakathil ninnu ooksijan ozhivaakkunnath eluppamaanu. ennirunnaalum, enn-doped conductive polymerukal vaanijyaparamaayi labhyamakaan saadhyathayilla.
jaiva tanmatra ardhachaalakangalil dopping.
hosttumaayi prosess cheiyunnathinulla anuyojyatha, athaayath samanamaaya baashpeekarana thaapanila allengil niyanthrikkaavunna layikkal enniva kaaranam dopping molecular ardhachaalakangalil molecular dopantukalkk munganana nalkunnu. koodaathe, loha ayoon dopantukalumaayi (lii +, emo6 + polullava) thaarathamyappeduthumbol thaarathamyena valia valippathilulla tanmatra dopantukal pothuve prayojanakaramaanu, ithu oledukal, jaiva sourorjja cellukal thudangiya multilayer gadanakalil upayogikkunnathinu mikacha speshyal thadassam nalkunnu. saadhaarana pii-type dopantukalil eph4-tii. sii. enn. kyu, emm. oo. (tii. eph. dii) 3 enniva ulppedunnu. ennirunnaalum, dopping conductive polymerukalil abhimukeekarikkunna prashnathinu samaanamaayi, kuranja electron affinity (iii. eiii) ulla vasthukkalkk anuyojyamaaya eyar-stable enn-dopantukal ippozhum avyakthamaanu. aduthide, [rukp ≤ mess] 2 polulla pilartthaavunna diameric dopantukalude samyojanathodukoodiya foto aaktiveshan, thaazhnna samudra padaarthangalil phalapradamaaya enn-dopping saakshaathkarikkunnathinu oru puthiya paatha nirddeshikkunnu.
magnetic dopping.
kanthika uthejakathekkurichulla gaveshanangal kaanikkunnath, nirddishta thapam polulla chila gunangalil ganyamaaya maattam varuthunnathu ashudhiyude cheria saandrathaye baadhichekkaam; udaaharanathinu, ardhachaalaka pheromagnetic aloykalile dopant maalinyangalkk vella, hogan, sul, nakamura ennivar aadyam pravachichathupole vyathyastha gunangal srishtikkaan kazhiyum.
kanthika ardhachaalaka mekhalayil nerppicha kaanthikatha nalkunnathinu dopant moolakangal ulppeduthunnathu vardhichuvarunna praadhaanyamullathaanu. chaarjinu purame electron spin upayogikkunna oru klaas sisttamaaya valarnnuvarunna spintronixinte pravarthanakshamathaykku disper ferro magnetic speesheesukalude saannidhyam pradhaanamaan. density functional thiyari (dii. eph. tii) upayogichu oru nischitha laattisinullile dopantukalude thapanilaye aasrayichulla kanthika swabhaavam candidate ardhachaalaka samvidaanangal thirichariyunnathinu maathrkayaakkaam.
ardhachaalakangalil single dopantukal.
dopantukalil oru ardhachaalakathinte savisheshathakalude sensitiivu aashrithathvam upakaranangal paryavekshanam cheiyunnathinum prayogikkunnathinum tunable prathibhaasangalude vipulamaaya shreni nalkiyittundu. vaanijya upakaranathinte prakadanatthilum ardhachaalaka vasthuvinte adisthaana gunangalilum oru otta dopentinte phalangal thirichariyaan kazhiyum. kwaandam vivarangalude mekhalayile single-spin upakaranangal allengil single-dopant traansistarukal polulla orotta dopantinte vyathiriktha swabhaavam aavasyamulla puthiya aaplikkeshanukal labhyamaayi. kazhinja dashakathile naadakeeyamaaya munnettangal, nireekshanam, niyantrithamaayi single dopantukal srishtikkal, kaikaaryam cheyyal, athupole thanne puthiya upakaranagalil avayude prayogam enniva solotronixinte (soolatti dopant opttoo electronics) puthiya mekhala thurakkaan anuvadichu.
modulation dopping.
dopping vazhi avatharippikkunna electronukaloo dwaarangalo chalanathmakamaanu, avaa avayil ninnu verpeduthiya dopant aattangalil ninnu praadeshikamaayi verthirikkaam. ionized daathaakkalum sweekarthaakkalum yathaakramam electronukaleyum dwaarangaleyum aakarshikkunnu, athinaal eee speshyal verthirikkalin baand gyaappinte (udha.jii. oru kwaandam kinner), allengil antharnirmmitha vaidyutha mandalangal (udha.jii. nonsentrosimetric christalukalude kaaryatthil). eee saankethikavidyaye modulation dopping ennu vilikkunnu, ithu valare uyarnna chalanathmakatha nedaan anuvadikkunna, marddicha carrier-donner chitharal kaaranam prayojanakaramaanu.