Light and lasers
From visible blue light to invisible extreme UV light, ASML’s lithography machines keep innovation in light and lasers moving forward
Throughout ASML’s history, we’ve supported chip manufacturers in making the transition to new lithography wavelengths that make more advanced microchips possible. Each step forward required innovation in how the light is generated, from visible blue light to ASML’s exclusive extreme ultraviolet (EUV) technology.
When ASML was founded, the state-of-the-art light source for lithography was the mercury vapor lamp. This generates light by passing electricity through a bulb that contains mercury. The current heats the mercury until it becomes a plasma that emits light of various wavelengths. The required wavelength was selected with an interference filter.
In the mid-1980s, the industry demand for smaller features led to another shift to shorter wavelengths. And this time, a whole new way of making light was needed: lasers. In particular, deep ultraviolet (DUV) excimer lasers. These lasers use mixtures of gases that don’t normally combine. However, when enough energy is applied, atoms of the two gases join together to form excited temporary molecules (excimers). The excited molecules release excess energy as light whose wavelength depends on the gases used.
第一个DuV系统使用基于两个元素的组合的准分子激光器：氪和氟。这些氪 - 氟化物（KRF）激光器产生波长为248纳米（NM）的光。150 nm KRF系统从前一条I-LINE系统的280 nm缩小特征尺寸。现代KRF系统现在可以产生低至80 nm的功能。
甚至进一步进入UV频谱，下一代DuV光刻系统使用氩 - 氟化物（ARF）准分子激光器，其产生具有193nm波长的光。启用此功能尺寸为38 nm待印刷。
Creating EUV light
EUV光刻, a technology entirely unique to ASML, uses light with a wavelength of 13.5 nanometers. This wavelength is more than 14 times shorter than DUV light.
In our laser-produced plasma (LPP) source, molten tin droplets of around 25 microns in diameter are ejected from a generator at 70 meters per second. As they fall, the droplets are hit first by a low-intensity laser pulse that flattens them into a pancake shape. Then a more powerful laser pulse vaporizes the flattened droplet to create a plasma that emits EUV light. To produce enough light to manufacture microchips, this process is repeated 50,000 times every second.
More about ASML technology
Providing highest resolution in high-volume manufacturing, ASML’s extreme ultraviolet lithography machines are pushing Moore’s Law forward.