Dab tsi yog qhov tseem ceeb ntawm SiC?

Silicon carbide (SiC)yog ib qho tseem ceeb dav bandgap semiconductor khoom siv dav hauv cov khoom siv hluav taws xob muaj zog thiab cov khoom siv hluav taws xob siab. Cov hauv qab no yog qee qhov tseem ceeb ntawmsilicon carbide wafersthiab lawv cov lus piav qhia ntxaws:

Lattice Parameters:
Xyuas kom meej tias cov lattice tas li ntawm cov substrate sib phim cov txheej txheem epitaxial kom loj hlob kom txo tau qhov tsis xws luag thiab kev ntxhov siab.

Piv txwv li, 4H-SiC thiab 6H-SiC muaj qhov sib txawv lattice, uas cuam tshuam rau lawv cov txheej txheem epitaxial zoo thiab kev ua haujlwm ntawm cov cuab yeej.

Stacking Sequence:
SiC yog tsim los ntawm silicon atoms thiab carbon atoms nyob rau hauv ib tug 1: 1 piv ntawm ib tug macro scale, tab sis qhov kev txiav txim ntawm lub atomic txheej yog txawv, uas yuav tsim txawv siv lead ua qauv.

Cov ntaub ntawv siv lead ua muaj xws li 3C-SiC (cubic structure), 4H-SiC (hexagonal structure), thiab 6H-SiC (hexagonal structure), thiab cov khoom sib txuas sib txuas yog: ABC, ABCB, ABCACB, thiab lwm yam. Txhua daim ntawv siv lead ua muaj cov khoom siv hluav taws xob sib txawv. cov yam ntxwv thiab lub cev muaj zog, yog li xaiv txoj cai siv lead ua daim ntawv yog qhov tseem ceeb rau kev siv tshwj xeeb.

Mohs Hardness: Txiav txim siab qhov hardness ntawm lub substrate, uas cuam tshuam qhov yooj yim ntawm kev ua thiab hnav tsis kam.
Silicon carbide muaj Mohs hardness siab heev, feem ntau yog nruab nrab ntawm 9-9.5, ua rau nws yog ib qho nyuaj heev rau cov ntawv thov uas yuav tsum tau hnav tsis kam.

Qhov ntom ntom: cuam tshuam rau lub zog txhua yam thiab thermal zog ntawm lub substrate.
High density feem ntau txhais tau tias zoo dua mechanical zog thiab thermal conductivity.

Thermal Expansion Coefficient: Hais txog qhov nce ntawm qhov ntev lossis ntim ntawm cov substrate txheeb ze rau qhov qub ntev los yog ntim thaum qhov kub thiab txias nce los ntawm ib degree Celsius.
Qhov haum ntawm lub substrate thiab txheej epitaxial nyob rau hauv qhov kub hloov pauv cuam tshuam rau thermal stability ntawm lub cuab yeej.

Refractive Index: Rau cov ntawv siv kho qhov muag, qhov ntsuas qhov taw qhia yog qhov tseem ceeb hauv kev tsim cov khoom siv optoelectronic.
Qhov sib txawv ntawm qhov ntsuas refractive cuam tshuam qhov nrawm thiab txoj hauv kev ntawm lub teeb tsis muaj zog hauv cov khoom.

Dielectric Constant: cuam tshuam rau cov yam ntxwv ntawm cov khoom siv.
Qhov qis dielectric tas li yuav pab txo cov kab mob parasitic capacitance thiab txhim kho cov cuab yeej ua haujlwm.

Thermal conductivity:
Qhov tseem ceeb rau kev siv hluav taws xob siab thiab kub kub, cuam tshuam rau kev ua kom txias ntawm lub cuab yeej.
Lub siab thermal conductivity ntawm silicon carbide ua rau nws zoo haum rau cov khoom siv hluav taws xob muaj zog vim tias nws tuaj yeem ua kom sov tawm ntawm lub cuab yeej.

Band-gap:
Hais txog lub zog sib txawv ntawm sab saum toj ntawm valence band thiab hauv qab ntawm cov khoom siv hluav taws xob hauv cov khoom siv semiconductor.
Cov ntaub ntawv dav dav xav tau lub zog ntau dua los txhawb cov kev hloov pauv hluav taws xob, uas ua rau silicon carbide ua tau zoo nyob rau hauv qhov kub thiab txias ib puag ncig.

Break-down Electrical Field:
Qhov txwv voltage uas cov khoom siv semiconductor tuaj yeem tiv taus.
Silicon carbide muaj qhov hluav taws xob tawg siab heev, uas tso cai rau nws tuaj yeem tiv taus qhov hluav taws xob siab heev yam tsis muaj kev tawg.

Saturation Drift Velocity:
Qhov siab tshaj plaws nruab nrab ceev uas cov neeg nqa khoom tuaj yeem ncav cuag tom qab qee qhov hluav taws xob tau siv rau hauv cov khoom siv semiconductor.

Thaum lub zog hluav taws xob nce mus rau ib theem, cov neeg nqa khoom nrawm yuav tsis nce ntxiv nrog kev txhim kho ntxiv ntawm cov hluav taws xob. Qhov nrawm ntawm lub sijhawm no yog hu ua saturation drift velocity. SiC muaj lub siab saturation drift tshaj tawm, uas muaj txiaj ntsig zoo rau kev ua tiav ntawm cov khoom siv hluav taws xob ceev ceev.

Cov kev ntsuas no ua ke txiav txim siab qhov ua tau zoo thiab kev siv tau ntawmSiC wafersnyob rau hauv ntau yam kev siv, tshwj xeeb tshaj yog nyob rau hauv high-power, high-frequency thiab high-temperature ib puag ncig.