Ma epitaxial layers anobatsira sei michina ye semiconductor?

Kwakatangira zita rekuti epitaxial wafer

Kutanga, ngatikurudzirei pfungwa diki: kugadzirira wafer kunosanganisira zvinongedzo zviviri zvikuru: kugadzirira substrate uye maitiro e epitaxial. Substrate iyi wafer yakagadzirwa nezvinhu zve semiconductor single crystal. Substrate inogona kupinda zvakananga mukugadzirwa kwewafer kuti igadzire zvishandiso zve semiconductor, kana kuti inogona kugadziriswa nemaitiro e epitaxial kuti igadzire epitaxial wafers. Epitaxy inoreva maitiro ekukura jira idzva rekristaro imwe chete pane substrate imwe chete yekristaro yakagadziriswa nekungwarira nekucheka, kukuya, kupukuta, nezvimwewo. Kristaro imwe itsva inogona kunge yakafanana ne substrate, kana kuti inogona kunge iri chinhu chakasiyana (chakafanana) epitaxy kana heteroepitaxy). Nekuti jira idzva rekristaro rinokura zvichienderana nechikamu chekristaro chesubstrate, rinonzi epitaxial layer (ukobvu hunowanzova ma microns mashoma, tichitora silicon semuenzaniso: zvinoreva kukura kwesilicon epitaxial kuri pasubstrate yesilicon single crystal ine kristaro chaiyo. jira rekristaro rine chimiro chakanaka chelattice uye resistivity yakasiyana uye ukobvu hune kristaro yakafanana nesubstrate inokura), uye substrate ine epitaxial layer inonzi epitaxial wafer (epitaxial wafer = epitaxial layer + substrate). Kana mudziyo wagadzirwa paepitaxial layer, unonzi positive epitaxy. Kana mudziyo wakagadzirwa pasubstrate, unonzi reverse epitaxy. Panguva ino, epitaxial layer inongotamba basa rekutsigira.

Waferi yakakweshwa

Nzira dzekukura kweEpitaxial

Molecular beam epitaxy (MBE): Iyi inyanzvi yekukura kwemasero epitaxial inoshandiswa pasi pemamiriro ekupisa zvakanyanya. Munzira iyi, zvinhu zvinobva pano zvinobviswa muchimiro chedanda remaatomu kana mamorekuru zvobva zvaiswa pachigadziko chekristalline. MBE inyanzvi yekukura kwemasero e semiconductor yakanyatsojeka uye inodzorwa inogona kudzora ukobvu hwezvinhu zvakachengetwa padanho reatomu.
Metal organic CVD (MOCVD): Mukuita kweMOCVD, organic metal nehydride gas N gas ine zvinhu zvinodiwa zvinopihwa kune substrate patembiricha yakakodzera, yoitwa chemical reaction kuti igadzire semiconductor material inodiwa, uye inoiswa pa substrate, ukuwo zvimwe zvinhu zvinosanganiswa nereaction products zvichiburitswa.
Vapor phase epitaxy (VPE): Vapor phase epitaxy tekinoroji inokosha inoshandiswa zvakanyanya mukugadzira zvishandiso zve semiconductor. Nheyo huru ndeyekutakura utsi hwezvinhu zve elemental kana compounds mugasi rinotakura, uye kuisa makristaro pa substrate kuburikidza nemakemikari.

Ndeapi matambudziko anogadziriswa ne epitaxy process?

Zvinhu zvekristaro imwe chete chete hazvigone kugutsa zvinodiwa pakugadzira michina yakasiyana-siyana ye semiconductor. Saka, kukura kwe epitaxial, tekinoroji yekukura kwechinhu chimwe chete chekristaro, yakagadzirwa pakupera kwa1959. Saka tekinoroji ye epitaxy inobatsira sei pakusimudzira zvinhu?

Kune silicon, apo tekinoroji yekukura kwesilicon epitaxial yakatanga, yaive nguva yakaoma chaizvo yekugadzira ma transistors esilicon ane frequency yakakura uye ane simba guru. Kubva pamaonero emisimboti ye transistor, kuti uwane frequency yakakura uye simba rakakwirira, voltage yekupwanyika kwenzvimbo yekuunganidza inofanira kunge yakakwira uye resistance ye series inofanira kunge iri diki, kureva kuti, kudonha kwe saturation voltage kunofanira kunge kudiki. Yekutanga inoda kuti resistivity yezvinhu munzvimbo yekuunganidza inofanira kunge yakakwira, nepo yekupedzisira ichida kuti resistivity yezvinhu munzvimbo yekuunganidza inofanira kunge yakaderera. Matunhu maviri aya anopesana. Kana ukobvu hwezvinhu munzvimbo yekuunganidza hukadzikiswa kuderedza resistance ye series, silicon wafer ichave yakatetepa uye isina kusimba kuti igadziriswe. Kana resistivity yezvinhu ikaderedzwa, inopesana nezvinodiwa zvekutanga. Zvisinei, kuvandudzwa kwetekinoroji ye epitaxial kwakabudirira. Yakagadzirisa dambudziko iri.

Mhinduro: Kura epitaxial layer ine resistivity high-resistance pane substrate ine resistance yakaderera zvakanyanya, uye gadzira mudziyo pa epitaxial layer. Iyi epitaxial layer ine resistivity high-resistivity inoita kuti chubhu ive ne high breakdown voltage, nepo substrate ine resistance yakaderera Inoderedzawo resistivity ye substrate, nokudaro ichideredza saturation voltage drop, nokudaro ichigadzirisa kusawirirana pakati pezviviri.

Pamusoro pezvo, matekinoroji epitaxy akadai se vapor phase epitaxy uye liquid phase epitaxy yeGaAs nedzimwe III-V, II-VI nedzimwe molecular compound semiconductor materials dzakagadzirwawo zvakanyanya uye dzava hwaro hwezvishandiso zvakawanda zve microwave, optoelectronic devices, simba. Iyi itekinoroji yemaitiro inokosha pakugadzirwa kwezvishandiso, kunyanya kushandiswa kwakabudirira kwe molecular beam uye metal organic vapor phase epitaxy tekinoroji muzvikamu zvitete, superlattices, quantum wells, strained superlattices, uye atomic-level thin-layer epitaxy, inova nhanho itsva mukutsvagisa kwe semiconductor. Kuvandudzwa kwe "energy belt engineering" mumunda kwakaisa hwaro hwakasimba.

Mukushandiswa kwazvino, zvishandiso zve semiconductor zvebandgap yakafara zvinowanzogadzirwa pa epitaxial layer, uye silicon carbide wafer pachayo inoshanda chete se substrate. Nokudaro, kutonga kwe epitaxial layer chikamu chakakosha cheindasitiri yebandgap yakafara.

Unyanzvi hukuru hunomwe mu epitaxy tekinoroji

1. Matanda epitaxial anoremerwa zvakanyanya (akaderera) anogona kurimwa pamatanda anodzivirira zvishoma (akakwirira).
2. Rutivi rweN (P) epitaxial runogona kukura paP (N) type substrate kuti rugadzire PN junction zvakananga. Hapana dambudziko rekugadzirisa kana uchishandisa nzira yekupararira kugadzira PN junction pane imwe crystal substrate.
3. Pamwe chete nehunyanzvi hwemasiki, kukura kwe epitaxial kwakasarudzwa kunoitwa munzvimbo dzakatarwa, zvichigadzira mamiriro ekugadzirwa kwemasekete akabatanidzwa uye zvishandiso zvine maumbirwo akakosha.
4. Rudzi uye huwandu hwedoping zvinogona kuchinjwa zvichienderana nezvinodiwa panguva yekukura kwe epitaxial. Kuchinja kwehuwandu hwedoping kunogona kuva kuchinja kamwe kamwe kana kuchinja zvishoma nezvishoma.
5. Inogona kukura ine mativi akasiyana-siyana, ine mativi akawanda, ine mativi akawanda uye ine mativi matete kwazvo ane zvikamu zvinoshanduka.
6. Kukura kweEpitaxial kunogona kuitwa patembiricha yakaderera pane inonyunguduka yezvinhu, mwero wekukura unogona kudzorwa, uye kukura kweepitaxial kweukobvu hweatomu kunogona kuwanikwa.
7. Inogona kukura zvinhu zvekristaro imwe chete zvisingakwanise kudhonzwa, zvakaita seGaN, makristaro imwe chete emakemikari etertiary nequaternary, nezvimwewo.