Although my first publications about the development of ISFETs, dated 1970 and 1972, suggest that this is the beginning of the ISFET “revolution”, in reality the research actually started in 1966. In this year my research effort in the field of biomedical measurements, especially those concerning the measurement of local ion concentration variations, could be extended in the direction of silicon electrodes, because at that time Professor Memelink started his MOS research at our University. This was a unique possibility to combine electrode development and MOS technology, leading to the development of ISFETs.
As a pioneer in this field I had to fright against various critical researchers who did not believe that it would ever be possible to use electronic devices in an electrolytic environment.
I remember that Professor Memelink visited the Stanford University in 1971 and after he returned he showed me some notes, about a Japanese professor who was also very active in this field and with convincing results. This turned out to be Professor Tadayuki Matsuo.
This message stimulated me to go on with my own experiments and resulted in less criticism in my surroundings. So, although Professor Matsuo did not published his results before 1974, I am still very indebted to the personal communication between him and the head of my project Professor Memelink, which encouraged me to proceed further along the difficult road of my pioneering work.
Perhaps it is a little late, but nevertheless thank you very much Professor Matsuo.
Also our personal contacts later are greatly appreciated.