How are microchips made? - George Zaidan and Sajan Saini

翻译人员: Yip Yan Yeung 校对人员: Marie Li

This is a computer chip, magnified 500 times.

这是一块计算机芯片， 放大了 500 倍。

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

你看到的是计算城市的俯瞰图，

with distinct neighborhoods for different functions.

不同的街区有不同的功能。

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

它们由长达 100 千米的 超细铜线相连，

running across 10 or more stacked levels.

横跨 10 多个堆叠层。

At the very bottom, billions of electronic devices

最底层，上亿个电子元器件 产生数字流量，穿过芯片。

generate the digital traffic that pulses across the chip.

The most common of these devices is called a transistor;

其中最常见的电子元器件 叫做“晶体管”，

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

它作为开关， 在承受电压时让电流流过。

Transistors can be as small as 20 nanometers,

晶体管可以小到 20 纳米，

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

一块芯片上可以安装 超过 500 亿个晶体管。

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

全球每年生产 超过 1 万亿块计算机芯片。

That’s about 20 trillion transistors built every second,

相当于每秒制造 大约 20 万亿个晶体管，

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

而且是在不到 500 座被称为 “晶圆厂”的制造工厂中制造的。

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

我们是如何如此迅速地制造 这么多又小又精密连接的元器件的？

so incredibly fast?

The answer involves a technology called photolithography,

答案与一种叫做“光刻”的技术有关，

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

它可以让我们同时制造 一块芯片上的所有元器件。

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

就像同时建造城市里所有的建筑物一样。

And with no tiny construction crews to help,

我们并没有微型的施工队来干活，

we build using light as a measuring and sculpting tool.

于是我们会把光 用作测量和雕刻工具。

The process starts with a wafer of silicon,

光刻工艺从硅片 （也称“晶圆”）开始，

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

将其浸泡在溶剂和酸剂中， 在送入烘箱之前清洗干净。

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

在烘箱中，氧气与晶圆发生反应， 形成一层二氧化硅。

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

然后将一种叫做“光刻胶”的液体 旋转涂上晶圆，加热硬化。

Next, ultraviolet light selectively illuminates the wafer,

接下来，紫外线照射部分晶圆，

by passing through or reflecting off a specialized mask.

穿过特定掩模版或由掩模版反射。

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

在被照射的区域， 反应会削弱光刻胶的化学键。

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

晶圆被浸入另一种化学试剂， 清洗经过削弱的光刻胶，

leaving an image of the mask.

留下掩模的图案。

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

刻蚀机的活性气体 会去除暴露的氧化物，

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

形成窗口，将掩模的图案 转移到晶圆表面。

An implanter then accelerates boron or phosphorus ions

然后，注入机加速硼或磷离子

and slams them into the patterned openings.

并将其猛击到图案的窗口中。

These atoms form electropositive or electronegative regions

这些原子（和离子） 形成正电或负电区域，

that change silicon’s conductivity,

改变了硅的电导率，

creating the foundation of the transistor switch.

从而构成了晶体管开关的基础。

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

但是刻蚀得到的氧化物窗口 有一种“凹槽效应”。

Before the next level of copper lines are added,

在安装下一层铜线之前，

this one’s uneven lines must be polished flat,

不平整的布线必须经过抛光平坦化，

to near-atomic precision, using a sophisticated grinding process

达到近原子精度，这种精密的抛光工艺

called chemical mechanical polishing, or CMP.

被称为“化学机械抛光”，或 CMP。

CMP uses a controlled slurry of sub-micron ceramic particles

CMP 操控亚微米陶瓷颗粒浆料

to gently scrape and flatten the bumpy features.

轻柔地刮擦、磨平凹凸不平的部分。

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

这些晶圆厂设备和其他工具 在一块晶圆上用了上千次，

to create and link transistors into computing logic gates,

制造、连接晶体管，制作成计算逻辑门，

and to make connected neighborhoods for memory storage and computation.

制作相连的存储和计算区域。

Fabs run around the clock,

晶圆厂全天候运行，

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

将晶圆从纯硅转化为上千块芯片 大约需要三个月。

into hundreds of chips.

With this continuous operation,

这种持续运行

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

使得晶圆厂消耗大量的电力、 水、溶剂、酸、碱、

process gases, and precious metals.

加工气体和贵金属。

Wafers are processed in ultra-high purity tool chambers,

晶圆在超高纯度的密闭反应舱中加工，

maintained by pumps running constantly,

由持续运行的泵维护， 维持类似于深空的真空状态。

to sustain a vacuum that resembles deep space.

High-temperature furnaces never turn off.

高温烘箱永远不会关闭。

Fab air handlers constantly expel filtered air

晶圆厂的空气处理器 不断排出过滤后的空气，

to corral dust and tiny particles away from wafers.

让灰尘和微小颗粒远离晶圆。

This takes a lot of electricity.

这需要大量的电力。

The chemicals and purified water used in cleaning

清洗使用的化学物质和超纯水

create nearly five gallons of waste per wafer run—

在每轮晶圆制造中 都会产生近五加仑的废料，

which needs to be filtered and pH treated.

必须经过过滤和 pH 值处理。

Meanwhile, CMP slurries are continually flushed with water

同时，CMP 浆料需要不断用水冲洗，

to keep their fine particles from forming chunks

避免细颗粒结块，磨断脆弱的铜线。

that would tear apart the fragile copper lines.

This adds five times more liquid waste.

这又增加了五倍的液体废料。

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

晶圆厂借助大量的氮气和氦气运行设备。

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

使用和由设备产生的其他气体 是温室气体的排放源。

To minimize their emission,

为了最大限度地减少排放，

machines called scrubbers decompose and dissolve some gaseous byproducts

称为“清洗机”的机器 会分解一些气态副产物

into treatable wastewater.

并将其溶解成可处理的废水。

That uses more electricity, and more water.

这消耗了更多的电力和水。

As computing complexity grows,

随着计算复杂性的增加，

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

需要更多的铜和贵金属来连接芯片。

And new problems arise:

新的问题出现了：

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

如今，基于 PFAS 的光刻胶 对制造更小的元器件至关重要。

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

但是环境中的全氟和多氟烷基废物 最终会进入我们的体内，

and it may be harmful.

可能有害。

Computer chips are modern marvels that have transformed our world—

计算机芯片是现代奇迹， 改变了我们的世界，

and the factories that build them are themselves engineering wonders.

制造计算机芯片的工厂 本身就是工程奇迹。

But as our demand for chips accelerates,

但是随着我们对芯片需求的加速，

their fabrication is hitting hard sustainability limits.

芯片制造已达到严格的可持续性极限。

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

有些地方已经开始限制农民用水，

in favor of running fabs.

迎合晶圆厂运行。

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

为了计算和环境的未来，

tomorrow’s leaner, cleaner, and greener fabs

未来更精简、更清洁、更环保的晶圆厂

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

必须比他们制造的芯片更智慧地运行。