Author's note

Being a chemical physicist and having learned something about semiconductor technology at Philips I decided in 1993 to start a research company, Aquamarijn, on filtration membranes made with micro machining technology for leukocyte filtration. The first micro engineered membranes were manufactured on 4 January 1994 in the MESA Clean Room of the University of Twente and were made after four months harsh micro machining labour by me having not many practical Clean Room experience. The membrane (two inch diameter) was called a microsieve and had pores of 5 micron in diameter. Of course the membranes, if you know the trick, can also be made in much less time, it is one of the most simple micro engineered products, in comparison to e.g. air bag sensors, flow sensors, micro motors etc..

New things never stay new, so the technology had to be developed in a quick pace mainly by Wietze Nijdam (since 1995) and myself with enthusiastic support of the micro-mechanics research group of Jan Fluitman and Miko Elwenspoek in the mid nineties.

New technology is only successful if at a given moment others want to take over and want to do research themselves or bring developed products to the market. An example of this is a large medical company that learned from the Aquamarijn technology and also applied for patents (1998) on leukocyte filtration applications. The original patent application of 1995 by Aquamarijn on e.g. polymeric embossed microsieves and laser interference lithography for the manufacturing of nanosieves is as well general as specific and nearly all of the later research have shown that the ideas were feasible. A number of articles were published, but the PR profile of Aquamarijn was kept relatively low. In the late nineties luckily other scientific institutes embraced the pioneering work and started also fundamental research on microsieves (University of California, since 1998), hydrogen separation membranes supported by microsieve (Massachusetts Institute of Technology, since 1999) and biomedical nanosieves with 20-50 nanometer sized pores (University of Illinois at Chicago, since 2000). After the achievement of nanosieve structures (Nanotechnology 1998) several nano-oriented research groups from the University of Twente asked for our technological support on topics as nano stencilling and photonic crystals, because the use of a nano engineered membrane may sometimes be a prerequisite in their nano applications.

Funding is never easy and it took much effort and creativity to find suitable sources. Aquamarijn owes a lot of financial gratitude towards the Dutch STW organisation and the SENTER and NOVEM subsidy programs from the Dutch government. Without their loyalty and support the Dutch Research BV's, in particular Aquamarijn, would have a very hard time. Luckily it seems that the investment climate in micro/nano engineering in the Netherlands is changing in a positive way by more co-financing of venture capitalists of start-up companies with a fair back-up fi'om the universities. Also the Dutch government of economic affairs (EZ) seems to gain more sympathy for micro and nano engineering technology and more incubating support will surely be welcomed by start-up companies with a mean grown-up time of at least five years.