In 1970, Toshiba started to get involved with CMOS. "For Toshiba, which was late in introducing the previous generation NMOS technology, trying to get a head start in CMOS was critical", writes Tsuyoshi Kawanishi, later CEO of Toshiba Semiconductors, in his book Chip Management.
Kawanishi lists the many challenges in getting CMOS into production:
1. Yields were only a few percent.
2.. We had only one ion implanter at the time, and it was constantly breaking down and we had to wait to get spare parts from the
3. The managers used to come on the line at 11pm to try to solve problems."
"Even more than those of us who were suffering on the production line, the top management of the company had a lot of headaches because we would lose money whenever deliveries were late", recounts Kawanishi, "but top management stood up against the stress pretty well, and those of us in production ploughed ahead."
Kawanishi concludes his account of the CMOS development with the words: "As a result of everybody's efforts Toshiba made sufficient progress in CMOS technology that we were able successfully to use it for the 1 Megabit RAM."
In this paragraph Kawansishi is being unduly modest. The 1Mbit DRAM was one of the most successful products Toshiba ever had, making hundreds of millions of dollars for the company.
The reason for that was, that after a number of chip companies sampled 1Mbit DRAMs and a lot of their customers designed them into end-products, it turned out that Toshiba was the only company which could manufacture 1Mbit DRAMs in high volume.
Toshiba enjoyed about six months as virtually the only supplier of the 1Mbit DRAM and, as a result, cleaned up massively in the market.
And those rewards were gleaned from all those hard, long, suffering nights struggling to get the bugs out of the CMOS process and its production line.
Great blog. I worked in Japan as a tech journalist at the time. At that time of semiconductor trade friction between Japan and the rest of the world, non-Japanese computer companies which very much sought after those Toshiba DRAMs were putting a lot of pressure on Kawanishi-san and Nishimuro-san at Toshiba. The result was that Toshiba kept close count of every DRAM, making sure that they were distributed fairly to Japanese and non-Japanese customers, so as to not worsen the already-bad trade friction. Again, great blog, and thanks, Dave.
yes, for sure, this was the biggest lead ANYONE ever had in DRAMs, since I started watching the market in the late 1970s. Everyone knew the main NMOS to CMOS transition was taking place at 1Mb generation and DRAMs would be CMOS thereafter, and Tosh hedged with both N- and CMOS DRAM 1Mb designs; when CMOS started to yield, they abandoned NMOS. Recall also, this was in the midst of fierce and acrimonious US-Japan trade spat, rising out of 1985 DRAM debacle that sent Intel and Mostek to the showers and thrust Japan into leadership in DRAMs. But then they saw Japan's bubble burst, and Samsung took over the lead in DRAMs, never to be headed off.
Nonetheless, Mr Kawanishi was an industry DRAM hero for all time for this success for Toshiba.
1970 was a bit early for CMOS DRAM wasn't it? I think the 1M DRAM was introduced around 1986. I guess you can read it that they spend 15 years on CMOS development before using it for the 1M DRAM. No disputing the Toshiba 1M DRAM was a spectacular success
Gary, yes of course 1970 was too early for CMOS DRAM. 1970 waqs the year Toshiba first started working to develop a CMOS process. I think CMOS DRAMs first came from Inmos (a 256K I believe) around 1980 and the 1Mbit, as you say, came around the mid-1980s.
Thanks Dave, great to hear from you. I was very well aware of your presence in Japan because whenever I went there I noticed the people I saw were a bit puzzled at the similarity of our names - Manners - Lammers and both of us Davids. I always I had the feeling they were a bit disappointed when I walked in and not you!
I agree Lane, Tosh should put up a statue to him because he got them into CMOS in the first place and saw it all the way through to this huge success.