An Intel Cleanroom Circa 1980

Summary : This video shows what it was like to work in a state-of-art fab during the late seventies to early eighties.

This video shows what it was like to work in a state-of-art fab during the late seventies to early eighties. It was taken inside an Intel four-inch wafer processing facility that was probably making critical dimension of 3 to 4 microns (a micron is 1000 nanometers). Almost everything was manual in those days. In the first scene of this video, an operator carefully removes a quartz 'boat' of wafers from a diffusion furnace and then loads in a second boat. In scene 1B, you can see an operator cleaning wafers in a bath. You can clearly see why these cleaning benches were called 'Dip-and-Dunk' tools. Then she pulls each one out by hand, drying it with a towel. The thick gloves and glasses were used to protect the operator from the solvents and acids used to clean the wafer. Companies relied heavily on training to prevent injuries in those days, as the idiot proofing that comes with automation was seldom available. Some of the most dangerous chemicals known to man were used. Yet semiconductor plants were among the safest factories to work in then. Scene 1D shows an operator taking a cassette of wafers out of a Dip-and-Dunk sink and putting them into a spin dryer. 1E shows the operator moving wafers with a vacuum wand. 1F shows how quartz boats had to be carefully pushed into a furnace to accommodate the ramp from room temperature to over 1000 degrees centigrade.

Scene 2 shows an inspection station. In those days it was done manually. Then come more scenes of dip-and-dunk areas. By scene 4, we move to the metallization area, where wafers are loaded on a planetary carrier. They were for the evaporation of aluminum onto the wafer to interconnect the transistors. That's what makes a bunch of transistors an integrated circuit. 4C, though dark, shows the bell jar of the vacuum evaporator being raised so these carriers can be put in.

Scene 5 shows an Ion Implanter. Note the manual controls and lack of computer control.

Scene 6 is an engineering workstation. No one would stack four cassettes like this today.

Scene 7 takes us back to an inspection area. This time it's in the yellow room where all the lithography is done.

Scene 8 shows Perkin Elmer projection aligners used to pattern wafers. Steppers had yet to come into use. They would not become commonplace until around 1981 or 1982. Mask levels still had to be aligned by hand. Computers could not do it yet. Notice the bare hands and bare faces. We had yet to learn that breath, hand oils, and skin flakes were a major source of yield loss.

Scene 9 shows the processing of the photoresist. It was pretty crude by modern day standards; wafers were put on a hot plate to bake the resist. But this was high tech in 1980! Instructions on how to operate the tool are papers, posted on the wall. In those days, computer screens were very rare. The spinning of photoresist on wafers, like a spinner that paints cards at a county fair, is still the best way to do it today. Note that these wafers are only three inches.

Copyright © 1981 by Intel. Reproduced with the verbal and implied permission of the Copyright Owner.

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