Lub platform granite mob siab rau cov chav huv: Tsis muaj hlau ion tso tawm, qhov kev xaiv zoo tshaj plaws rau cov khoom siv tshuaj xyuas wafer.

Hauv kev tshuaj xyuas semiconductor wafer, qhov huv ntawm chav huv si yog ncaj qha cuam tshuam nrog cov khoom tsim tawm. Raws li qhov tseeb ntawm cov txheej txheem tsim khoom chip txuas ntxiv txhim kho, qhov yuav tsum tau ua rau cov platform nqa khoom ntawm cov khoom siv kuaj pom tau dhau los ua nruj dua. Granite platforms, nrog lawv cov yam ntxwv ntawm xoom hlau ion tso tawm thiab qis particle pollution, tau dhau los ntawm cov khoom siv stainless hlau ib txwm muaj thiab dhau los ua qhov kev daws teeb meem zoo tshaj plaws rau cov khoom siv tshuaj xyuas wafer.

Granite yog ib lub pob zeb igneous ntuj tsim los ntawm cov zaub mov tsis yog hlau xws li quartz, feldspar thiab mica. Qhov no ua rau nws muaj qhov zoo ntawm xoom hlau ion tso tawm. Qhov sib piv, stainless hlau, ua ib qho hlau sib xyaw ntawm cov hlau xws li hlau, chromium thiab nickel, feem ntau raug electrochemical corrosion ntawm nws qhov chaw vim yog qhov dej vapor thiab acidic lossis alkaline gases hauv chav huv, ua rau muaj cov hlau ions xws li Fe²⁺ thiab Cr³⁺ nag. Thaum cov ions me me no txuas rau ntawm qhov chaw ntawm lub wafer, lawv yuav hloov cov khoom hluav taws xob ntawm cov khoom siv semiconductor hauv cov txheej txheem tom ntej xws li photolithography thiab etching, ua rau threshold voltage drift ntawm lub transistor, thiab txawm tias ua rau luv luv circuits hauv lub circuit. Cov ntaub ntawv xeem ntawm lub tsev kawm ntawv qhia tau hais tias tom qab lub platform granite raug tas li raug rau qhov kub thiab txias hauv chav huv simulated (23 ± 0.5 ℃, 45% ± 5% RH) rau 1000 teev, qhov tso tawm ntawm cov hlau ions qis dua qhov kev txwv nrhiav pom (< 0.1ppb). Tus nqi tsis zoo ntawm cov wafers uas tshwm sim los ntawm cov hlau ion sib kis thaum siv cov platforms stainless hlau tuaj yeem siab txog li 15% txog 20%.

Hais txog kev tswj cov khoom me me uas ua rau muaj kuab paug, cov platform granite kuj ua tau zoo heev. Cov chav huv muaj qhov yuav tsum tau ua kom muaj cov khoom me me uas raug tshem tawm hauv huab cua ntau heev. Piv txwv li, hauv ISO Class 1 chav huv, tus naj npawb ntawm 0.1μm cov khoom me me uas raug tso cai rau ib lub cubic meter tsis pub tshaj 10. Txawm tias lub platform stainless hlau tau dhau los ntawm kev kho polishing, nws tseem yuav tsim cov hlau khib nyiab lossis oxide nplai tev tawm vim yog cov zog sab nraud xws li kev co ntawm cov khoom siv thiab kev ua haujlwm ntawm cov neeg ua haujlwm, uas tuaj yeem cuam tshuam rau txoj kev pom kev lossis khawb qhov chaw ntawm lub wafer. Cov platform granite, nrog lawv cov qauv mineral ntom ntom (qhov ceev ≥2.7g / cm³) thiab qhov nyuaj siab (6-7 ntawm Mohs nplai), tsis yooj yim hnav lossis tawg thaum siv ntev. Cov kev ntsuas ntsuas qhia tau tias lawv tuaj yeem txo qhov concentration ntawm cov khoom me me uas raug tshem tawm hauv huab cua ntawm thaj chaw khoom siv kuaj pom ntau dua 40% piv rau cov platform stainless hlau, ua kom cov qauv chav huv zoo.

Ntxiv rau nws cov yam ntxwv huv si, kev ua tau zoo ntawm cov granite platforms kuj tseem ntau dua li ntawm cov hlau tsis xeb. Hais txog kev ruaj khov thermal, nws cov coefficient ntawm thermal expansion tsuas yog (4-8) × 10⁻⁶ / ℃, tsawg dua ib nrab ntawm cov hlau tsis xeb (kwv yees li 17 × 10⁻⁶ / ℃), uas tuaj yeem tswj tau qhov tseeb ntawm cov khoom siv kuaj pom thaum qhov kub hauv chav huv si hloov pauv. Lub zog damping siab (damping ratio > 0.05) tuaj yeem ua rau lub zog ntawm cov khoom siv sai sai thiab tiv thaiv qhov kev soj ntsuam kom tsis txhob co. Nws qhov kev tiv thaiv corrosion ntuj ua rau nws nyob ruaj khov txawm tias thaum raug rau cov tshuaj photoresist, cov roj etching thiab lwm yam tshuaj tsis tas yuav tsum tau tiv thaiv ntxiv.

Tam sim no, cov platform granite siv dav hauv cov chaw tsim khoom wafer siab heev. Cov ntaub ntawv qhia tau tias tom qab siv lub platform granite, qhov kev txiav txim siab tsis raug ntawm kev tshawb pom cov khoom me me ntawm wafer tau txo qis 60%, lub voj voog calibration ntawm cov khoom siv tau ntev dua peb zaug, thiab tus nqi tsim khoom tag nrho tau poob qis 25%. Raws li kev lag luam semiconductor txav mus rau qhov tseeb dua, cov platform granite, nrog lawv cov txiaj ntsig tseem ceeb xws li xoom hlau ion tso tawm thiab qis cov khoom me me, yuav txuas ntxiv muab kev txhawb nqa ruaj khov thiab txhim khu kev qha rau kev tshuaj xyuas wafer, ua lub zog tseem ceeb tsav tsheb kev nce qib ntawm kev lag luam.