Qhia luv luv plaub txoj hauv kev ntawm Wafer Thinning

Plaub txheej txheem txheej txheem rau wafer thinning muaj ob pawg: sib tsoo thiab etching.
(1) Mechanical sib tsoo
(2) Chemical mechanical planarization
(3) ntub dej etching
(4) Plasma Dry Chemical Etching (ADP DCE)
Kev sib tsoo siv kev sib xyaw ua ke ntawm kev sib tsoo lub log thiab dej los yog cov tshuaj slurries kom hnov ​​​​mob nrog thiab nyias cov wafer, thaum etching siv cov tshuaj los ua kom nyias cov substrate.
Sib tsoo:
◆ Kev sib tsoo tshuab
Mechanical (Conventional) Sib Tsoo - Cov txheej txheem no muaj tus nqi siab ntawm thinning, ua rau nws cov txheej txheem ntau heev. Nws siv lub pob zeb diamond thiab resin-bonded sib tsoo log mounted ntawm lub siab ceev spindle, zoo ib yam li cov siv nyob rau hauv spin-txheej daim ntaub ntawv. Daim ntawv qhia kev sib tsoo txiav txim siab qhov ceev ntawm spindle nrog rau cov khoom tshem tawm tus nqi.
Txhawm rau npaj rau kev sib tsoo tshuab, lub wafer tau muab tso rau ntawm lub tshuab nqus tsev vacuum thiab tuav hauv qhov chaw los ntawm lub tshuab nqus tsev. Lub nraub qaum ntawm lub wafer yog muab tso rau ntawm lub log sib tsoo, thaum txoj hlua abrasive muab tso rau ntawm sab xub ntiag ntawm lub wafer kom tsis txhob muaj kev puas tsuaj rau lub wafer thaum lub sij hawm thinning. Thaum cov dej deionized yog txau rau ntawm lub wafer, ob lub zog tig mus rau qhov sib txawv kom ntseeg tau tias muaj lubrication txaus ntawm lub log sib tsoo thiab lub substrate. Qhov no kuj tswj qhov kub thiab txias npaum li cas los xyuas kom meej tias lub wafer tsis yog av nyias.
Cov txheej txheem yog ob kauj ruam txheej txheem:
1. Kev sib tsoo ntxhib ua feem ntau ntawm cov refining ntawm tus nqi ntawm ~ 5μm / sec.
2. Kev sib tsoo zoo nrog 1200 txog 2000 grit thiab poligrind. Feem ntau tshem tawm ~ 30µm ntawm cov khoom ntawm tus nqi tsawg dua lossis sib npaug rau 1µm / sec thiab muab qhov kawg ua tiav ntawm wafer.
Lub 1200-grit muaj qhov ntxhib tiav nrog cov cim pom pom, thaum lub 2000-grit tsawg dua tab sis tseem muaj qee qhov hnav. Poligrind yog cov cuab yeej polishing uas muab lub zog siab tshaj plaws wafer thiab tshem tawm feem ntau ntawm cov av puas.
◆ Chemical Mechanical Planarization (CMP)
Chemical Mechanical Planarization (CMP) - Cov txheej txheem no ua rau lub wafer flattens thiab tshem tawm qhov tsis sib xws. CMP yog ua los ntawm cov khoom me me abrasive tshuaj slurries thiab polishing pads. Muab ntau hom phiaj ntau dua li kev sib tsoo tshuab.
CMP muab faib ua peb kauj ruam:
1. Mount lub wafer rau ntawm lub backside membrane, xws li ib tug wax tuav, tuav nws nyob rau hauv qhov chaw.
2. Siv cov tshuaj slurry los ntawm saum toj no thiab faib nws tusyees nrog polishing ncoo.
3. Tig lub polishing ncoo rau kwv yees li 60-90 vib nas this ib buff, nyob ntawm qhov kawg thickness specifications.
CMP grinds ntawm tus nqi qeeb dua li kev sib tsoo tshuab, tshem tawm tsuas yog ob peb microns. Qhov no ua rau nyob ze zoo meej flatness thiab tswj tau TTV.
Etching:
◆ Kev ntub dej
Etching siv cov tshuaj ua kua los yog etchants tshem tawm cov khoom los ntawm wafer, uas yog qhov tseem ceeb thaum tsuas yog ib feem ntawm lub wafer yuav tsum tau thinned. Los ntawm muab lub npog ntsej muag tawv rau ntawm lub wafer ua ntej etching, thinning tsuas yog tshwm sim ntawm ib feem ntawm lub substrate uas tsis muaj substrate. Muaj ob txoj hauv kev ua haujlwm ntub dej: isotropic (uniform nyob rau hauv tag nrho cov lus qhia) thiab anisotropic (uniform nyob rau hauv txoj kev ntsug).
Cov kua etchants txawv nyob ntawm qhov xav tau tuab thiab seb puas yog isotropic lossis anisotropic etching yog xav tau. Hauv isotropic etching, feem ntau etchant yog kev sib xyaw ntawm hydrofluoric acid, nitric acid, thiab acetic acid (HNA). Cov anisotropic etchants feem ntau yog potassium hydroxide (KOH), ethylenediaminecatechol (EDP) thiab tetramethylammonium hydroxide (TMAH). Feem ntau cov kev tshwm sim tshwm sim ntawm tus nqi ntawm ~ 10 μm / min, thiab cov tshuaj tiv thaiv yuav txawv nyob ntawm qhov etchant siv hauv cov tshuaj tiv thaiv.
◆ Plasma (ADP) Qhuav Etching (DCE)
ADP DCE yog qhov tseeb wafer thinning tshuab, zoo ib yam li ntub dej etching. Es tsis txhob siv kua, qhuav tshuaj etching siv plasma los yog etchant gases kom tshem tawm cov khoom. Txhawm rau ua cov txheej txheem thinning, ib lub teeb ntawm cov khoom kinetic heev tuaj yeem raug rho tawm ntawm lub hom phiaj wafer, cov tshuaj ua rau lub ntsej muag wafer, los yog ob qho tib si ua ke. Qhov kev tshem tawm ntawm qhuav etching yog hais txog 20μm / min, thiab tsis muaj kev ntxhov siab lossis tshuaj lom neeg, yog li txoj kev no tuaj yeem tsim cov wafers nyias nrog cov khoom zoo.