In 1960, transistor output reached one million units a month. In anticipation of further production increases, it was decided that the main plant at Gotenyama alone was too small. The search for a suitable factory site outside Tokyo began.
In essence, the semiconductor plant required four basic prerequisites: expansive land, a plentiful water supply, the presence of as little dust as possible and easy access. In terms of easy access, Tokyo would have been the optimal site, but metropolitan zoning laws placed various restrictions on factory construction.
The vicinity between northern Hiratsuka and Atsugi in Kanagawa was chosen. Atsugi was selected for its proximity, 46 kilometers from Tokyo and 32 kilometers from Yokohama, and its potential as a "satellite" city to the metropolitan area. Sony officials also gambled that an interchange would be built off the planned highway, later named the Tomei Expressway, which was to connect Tokyo and Osaka. This would make Atsugi much more accessible. The abundance of land was the major factor in choosing Atsugi though. At the time, the only industries based in Atsugi were a few automotive parts factories. The area was known primarily for hog raising and its strawberry fields.
Local residents and indeed even the Sony personnel searching for plant sites would have been astonished to know that a modern semiconductor plant would be built in this silo-dotted region.
Actually, Atsugi had been considered much earlier, but was later dropped from the list of potential sites. The problem was determining who had jurisdiction over the farm land. The area, which residents called "Kawara," or "river bed," was once the bed of the Sagami River and was planted with wheat, mulberries, peanuts and radishes. Had it been woods, plains or mountains, things would have been simple. Because it was farm land, however, it was subject to restrictions by the Ministry of Agriculture and Forestry which overrode its designation as a site for industrial development.
As prospects for resolving the jurisdiction problem appeared optimistic, Sony officials decided to accept the invitation from the Atsugi municipal authorities. In all, the site encompassed 165,290 square meters, with 115,703 square meters for the factory site and the remaining 49,587 square meters set aside for male and female dormitories. Land was purchased from some 180 landlords, despite the unknown whereabouts of some of them and the resulting time delays in the transactions.
It was a bold investment for Sony, but a good one. At that time, the price paid for this much land in Atsugi would only buy 9,900 square meters in Tokyo.
The next question was the plant's design. It was to have the latest equipment and facilities and an optimum design for a semiconductor plant. Iwama showed the worried designers a photograph of a recently built Texas Instruments semiconductor plant in Dallas, Texas. Designers referred to the photo as Sony designed its new factory.
The designers' biggest concern was dust, which would cripple transistors. Located in the middle of the Sagami plain, Atsugi was exposed to the full force of fierce winter winds which limited visibility to one meter or less. The designers actually walked about in February dust storms to see this for themselves. It was worse than they had dreamed. After taking into account all meteorological and topographical factors, it was decided that windows would open on the north side only. Unlike the main plant, however, the Atsugi plant would only use electrostatic dust collectors rather than conventional dust collectors, which were an expensive undertaking.
On November 1, 1960, the Sony Atsugi plant was completed. Toshiro Sakota was its first plant manager.
At the ceremony commemorating its completion, Ibuka noted "Sony must increase exports and contribute to Japan's economic prosperity. To succeed, we must produce economical, high quality transistorized products for the world market. Atsugi will be the focal point for carrying out this policy. I hope that with the cooperation of all residents, this plan will become a success."