How are microchips made? - George Zaidan and Sajan Saini

Translator: Kate Chan Reviewer: Xi He

This is a computer chip, magnified 500 times.

呢個係一塊放大咗500倍嘅電腦晶片。

What you’re looking at is the top of a computing city,

你睇緊嘅係一個計算機城市嘅頂端，

with distinct neighborhoods for different functions.

裡面有唔同功能嘅唔同社區。

They’re linked by up to 100 kilometers of ultra-thin copper lines,

佢哋畀長達100公里嘅超細銅線連接住，

running across 10 or more stacked levels.

有10個或以上嘅堆疊層次。

At the very bottom, billions of electronic devices

喺最底層，有幾十億個電子裝置

generate the digital traffic that pulses across the chip.

喺晶片上產生流動嘅數碼流量。

The most common of these devices is called a transistor;

呢啲裝置當中，最常見嘅係晶體管

it’s a switch that allows current to flow if it receives a voltage.

佢係一個開關，收到電壓，會畀電流流動。

Transistors can be as small as 20 nanometers,

晶體管可以細到20納米，

and more than 50 billion of them can fit on a single chip.

喺一塊晶片上面可以放超過500億個。

Globally, we produce more than a trillion computer chips every year.

全球每年會生產超過一萬億塊電腦晶片。

That’s about 20 trillion transistors built every second,

即係，每秒大約20萬億個晶體管，

and it’s done in fewer than 500 fabrication plants, known as fabs.

由少過500間製造廠（晶圓廠）生產。

How do we build so many tiny, intricately-connected devices,

我哋究竟點樣咁快建立

咁多個微小、錯綜複雜嘅裝置？

so incredibly fast?

The answer involves a technology called photolithography,

答案涉及一種技術，叫做光刻，

which helps us build all the devices on a chip simultaneously.

佢幫我哋喺晶片上，同時建立所有裝置。

It’s like constructing all the buildings in a city at the same time.

就好似喺一座城市入面，

同時建造所有嘅建築物噉。

And with no tiny construction crews to help,

我哋冇微小嘅建築工人幫手，

we build using light as a measuring and sculpting tool.

建造時，用光來測量同雕刻。

The process starts with a wafer of silicon,

呢個過程由一塊矽片開始，

which is doused in solvents and acids to strip it clean before entering a furnace.

浸佢入溶劑同酸，清理乾淨，然後入爐。

Here, oxygen gas reacts with the wafer to form a layer of silicon dioxide.

期間，氧氣同矽片反應，形成一層二氧化矽

Then, a liquid called “photoresist” is spun on and baked to harden.

再將一種叫做光刻劑嘅液體旋轉噴上去，

然後焗到硬化。

Next, ultraviolet light selectively illuminates the wafer,

下一步，紫外線會選擇性噉照亮晶片

by passing through or reflecting off a specialized mask.

透過穿透或者反射喺一個光罩。

In the lit areas, a reaction weakens the photoresist’s chemical bonds.

喺照明嘅地方，

化學反應會減弱光刻劑嘅化學鏈。

The wafer is doused in another chemical to wash away that weakened photoresist,

矽片會畀浸入另一種化學物質，

嚟洗走弱化咗嘅光刻劑，

leaving an image of the mask.

顯露出光罩嘅形象。

And an etching machine’s reactive gases remove the exposed oxide,

蝕刻機嘅反應性氣體

會去除露出嚟嘅氧化物，

creating windows that drill the mask’s pattern down to the wafer surface.

生成窗口，俾光罩嘅圖案鑽入晶片表面。

An implanter then accelerates boron or phosphorus ions

然後，植入器會將硼或磷離子加速

and slams them into the patterned openings.

將佢哋撞入圖案嘅開口。

These atoms form electropositive or electronegative regions

這些原子形成正電性或負電區域

that change silicon’s conductivity,

改變矽的導電率，

creating the foundation of the transistor switch.

製造出晶體管嘅開關。

The etched oxide windows, however, create hill-and-valley features.

但係，蝕刻嘅氧化物窗口會使晶片

有粒粒突突嘅特徵。

Before the next level of copper lines are added,

喺加入下一層銅線之前，

this one’s uneven lines must be polished flat,

一定要將呢一層嘅唔均勻

to near-atomic precision, using a sophisticated grinding process

用化學機械拋光 （CMP）精細研磨

called chemical mechanical polishing, or CMP.

令平整度精確到近原子水平

CMP uses a controlled slurry of sub-micron ceramic particles

CMP用受控嘅亞微米陶瓷顆粒漿料

to gently scrape and flatten the bumpy features.

嚟輕輕刮走同磨平個啲粒粒突突。

These fab tools, and many others, are used hundreds of times on a wafer,

呢啲晶圓廠工具，同其他工具，

用喺晶片上面幾百次，

to create and link transistors into computing logic gates,

嚟建立同連接晶體管同埋邏輯門，

and to make connected neighborhoods for memory storage and computation.

嚟建立連接嘅儲存同計算區域。

Fabs run around the clock,

晶圓廠係全天候運轉，

and it takes about three months to transform a single wafer from pure silicon

要大概三個月

將純矽片轉變成單一晶片

into hundreds of chips.

再變成幾百塊晶片。

With this continuous operation,

透過連續嘅操作，

fabs consume huge amounts of electricity, water, solvents, acids, bases,

晶圓廠消耗大量嘅電力、水、溶劑、酸、碱、

process gases, and precious metals.

工藝氣體同稀有金屬。

Wafers are processed in ultra-high purity tool chambers,

晶片喺超高純度工具室內加工而成，

maintained by pumps running constantly,

近似深空嘅真空環境

to sustain a vacuum that resembles deep space.

由持續嘅泵氣來維持。

High-temperature furnaces never turn off.

高溫爐永遠唔會閂。

Fab air handlers constantly expel filtered air

空氣處理器不斷排出過濾咗嘅空氣

to corral dust and tiny particles away from wafers.

令塵埃同微小粒子遠離晶片。

This takes a lot of electricity.

呢個過程需要好多電。

The chemicals and purified water used in cleaning

每次運行產生近五加侖嘅廢料，

create nearly five gallons of waste per wafer run—

所以，用過嘅清潔化學物質同純淨水

which needs to be filtered and pH treated.

需要過濾同pH處理。

Meanwhile, CMP slurries are continually flushed with water

同時，CMP漿液持續被水沖洗

to keep their fine particles from forming chunks

防止佢嘅細粒子成塊，

that would tear apart the fragile copper lines.

以致撕裂脆弱嘅銅線。

This adds five times more liquid waste.

呢個過程會增加五倍嘅液體廢料。

Fabs plow through vast amounts of nitrogen and helium gas to run their tools.

晶圓廠需要大量氮氣同氦氣

去運行佢嘅工具

And other gases used and generated in these tools are greenhouse contributors.

其他用工具需要嘅氣體同埋產生嘅氣體

都會造成溫室效應。

To minimize their emission,

一個叫洗滌器嘅機器，會分解同溶解

machines called scrubbers decompose and dissolve some gaseous byproducts

一啲氣體副產品，將佢哋變成

可處理嘅廢水， 將排放量減到最低

into treatable wastewater.

That uses more electricity, and more water.

呢個過程要用更多嘅電同埋水。

As computing complexity grows,

隨住計算嘅複雜度嘅增加，

more copper and precious metals are needed to link up chips.

需要更多銅同稀有金屬嚟連接晶片。

And new problems arise:

於是，有新嘅問題出現：

today, PFAS-based photoresists are essential to make ever-smaller features.

製造更細嘅特徵必須

用基於PFAS嘅光刻膠係。

But PFAS waste in the environment is ending up in our bodies,

但係，流入環境裏邊嘅PFAS廢物

最後會進入我哋嘅身體，

and it may be harmful.

可能有害。

Computer chips are modern marvels that have transformed our world—

電腦晶片係改變咗我哋嘅世界嘅現代奇蹟— ，

and the factories that build them are themselves engineering wonders.

製造佢哋嘅工廠本身亦係工程奇蹟。

But as our demand for chips accelerates,

但係，我哋對晶片嘅需求嘅大大增加，

their fabrication is hitting hard sustainability limits.

會挑戰晶片製造嘅可持續性嘅極限。

Already, some places are beginning to ration water to farmers,

已經有啲地方開始緊減少對農民嘅供水，

in favor of running fabs.

以保證晶圓廠嘅運行。

For the sake of the future of computing and our environment,

為咗電腦計算同我哋嘅環境嘅未來，

tomorrow’s leaner, cleaner, and greener fabs

明日更精簡，更清潔，同更環保嘅工廠

will need to run even smarter than the very chips they build.

需要運作得比佢哋生產嘅晶片更聰明。