They must have enough confidence in a superior system to disclose this. Still though, it's best to keep the cards close to your chest until it's time to play
News on China's scientific and technological development.
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A micromachined Joule-Thomson cryocooler for ice lithography.
Abstract
A micromachined Joule-Thomson cryocooler has been designed as a cryostage for ice lithography, which allows high-pressure nitrogen throttling to liquefy and fast cool samples with low vibration. The sample can be cooled down to 99.5 K in 30 min and then heated up to room temperature in 10 min. Compared with previous cooling systems based on liquid nitrogen, the Joule-Thomson cryostage has resulted in a significant 90% reduction in cooling time and a decrease in operating temperature by 30 K. Besides, the nitrogen mass-flow rate beneath the sample remains <20 mg/s to minimize vibration. The measured peak-to-peak amplitude at the minimum temperature is about 5.6 nm. As the first cooler integration within an ice lithography system, this Joule-Thomson cryostage not only enables the exploration of a wider range of ice resists, but also can be applied in kinds of microscopes for helping characterize materials at cryogenic temperatures.
Introduction
Ice lithography (IL), an emerging direct-write lithography technique, has shown great potential for nano-scale fabrication [[1], [2], [3], [4], [5], [6]]. This technique is eco-friendly, compatible-to-substrate [7] and streamlined due to starting with vapor-deposited ice film on a pre-cooled substrate and lift-off by heating up the sample. Such principle means the substrate must be cooled to a cryogenic temperature. In the initial IL system [8], a liquid nitrogen (LN2) dewar is incorporated with an electron-beam lithography (EBL) system, using a cooper braid for substrate cooling. This process usually requires 3 h to achieve the lowest temperature of 130 K and >4 h to heat up to room temperature. One side, the minimum cooling temperature directly affects the ice quality and limits the exploration of ice resists with lower condense temperatures. Another side, the long cooling and heating times significantly reduce the fabrication efficiency. To address these problems, R. I. Haque et al. [9] introduced LN2 below the substrate via flexible stainless steel tubes instead of a copper braid. The modification allows the substrate to be rapidly cooled to 78.8 K in 20 min and heated up to room temperature in 10 min. They also demonstrated the use of organometallic tungsten hexacarbonyl in this system as a precursor, proving the importance of developing a new cooling sub-system with lower cooling temperatures for IL [10]. However, the vibration reached about 200 nm at 78.8 K due to LN2 boiling, thereby reducing the fabrication resolution.
I've actually seen some theories about how scmp might actually be an outlet for signalling stuff (to US for example).
As it is a 'private' company with 'little influence from Beijing', not to mention is usually being considered as somewhat anti-CPC as well.
So the theory then goes, that it allows to the PLA/CPC to send messages (look, we might have this capability) while also having the ability to deny.
Personally not sure (leaning more that it's not true, and it really is simply someone in scmp just posting about public papers).
This could be it, China is still biding time so any news that helps the doves in Pentagon should be encouraged until Beijing is confident to carry out AR
It's Stephen Chen, the same guy who always portrays research papers as something they aren't. Textbook clickbait. Do a search on this forum for his name, you'll get plenty of examples.
Maybe they have something even better. That is why they are disclosing this obsolete technology.
I really have trouble understanding how research like this is not classified as secret while at the same time the entire Chinese semiconductor industry is becoming basically a giant black box.
Perhaps, given recent events in the Middle East it’s time to start making deterring revelations. Perhaps, we are at the moment of maximum danger, and it’s time to reveal.
Or perhaps this paper could be used by another country with a stealth fighter problem.
Or perhaps this paper could be used by another country with a stealth fighter problem.
Revelation of this capability also can have strategic deterrent effect against the US given impact on all other stealth planes, including B2 and B21. It is not something that can be solved or countered by knowledge of its existence, hence the reveal. Kind of like how knowledge of true Chinese hypersonics (not the fake kind Western media and politics has decided to rank ballistic missiles as, to conceal their own lack of capability) has a deterrent effect against the West.