What we for the sake of convenience call a chip is officially called an IC the abbreviation for the integrated circuit. A chip is like a city, a city with no people but bursting with activity. A chip is packed with industrial building control centers in the form of components such as transistors and resistors which together form one huge network. The chips infrastructure carries vast amounts of fast traffic along roads and communication networks. The building blocks in chips are not only becoming ever smaller but designers are also making the chips cleverer all the time to create new possibilities continuously this makes the equipment controlled by the chip better, safer, easier to operate more energy efficiently, and friendlier to the environment. Let’s drive in seven-league boots through the ingenious process using which products such as chips are produced. A chip is an extremely small silicon plate ranging from a couple to several dozen square millimeters in size. This tiny silicon plate is then filled up with a great number sometimes millions of microelements such as transistors, diodes, or resistors which together form an integrated circuit of the IC.
A large number of chips are made on a round silicon disk called a wafer or slice at once. First of all, a new layer of silicon is created on the slice one-hundredth of a millimeter thick, then the silicon layer is oxidized in an oven so that an even thinner insulating layer is created on top of it. Then a coat of light-sensitive lacquer is applied to the slice. The lacquer is exposed through a kind of photographic negative so that the lacquer dissolves in certain places then in the places where there are no more lacquer atoms with great accuracy is shoot through the oxidized layer into the silicon. The layer of lacquer is there no longer required and is therefore removed from the slice. They ensure that the atoms penetrate a little deeper into the silicon by a few thousandths of a millimeter. A new silicon layer is applied over the oxide layer and once again a layer of lacquer is applied exposed and developed. The silicon which is uncovered by this process is then etched to way. Another series of treatments involving lacquering, exposure bombardment with atoms that penetrate the silicon. New oxide layers etc. are performed until the whole pattern is complete in all layers. Some 300 to 400 process steps are required along with 15 to 20 different masks with microscopically small patterns. The final step in the process is the connection of the various almost invisible tiny elements in the silicons. This is how an IC is made.
Silicon is made from ordinary quartz sand and rods of silicon are then created or drawn at extremely high temperatures. Thin slices are then sawn off these rods with great accuracy. ICs will be produced on these slices of silicon for which purpose the slices will undergo 300 to 400 processes. The first step is in the special oven the slices are covered by a new thin layer of very pure silicon into which the transistors and other components can be built. The slices with a new layer of silicon are placed in other boxes where the silicon is allowed to oxidize. This insulating oxide layer can be removed at a later stage when necessary. Then the slices are taken to a yellow room where extremely intelligent fully automated machines are used to apply the light-sensitive layer of lacquer to the oxide on the slices and to expose the slices. Yellow light is used in these rooms as the lacquer is not sensitive to this. The patterns on the masks a kind of photographic negative are of course are designed by development engineers. In these so-called implants is specific atoms can be shot into the unprotected areas of the silicon to give them a positive and negative conductivity. This is done incredibly accurately. One of the next steps of the process is etching removing material locally from the slices with great accuracy. This department uses an automatically controlled process involving acids and caustics. Another technique used is a dry etching with an etching gas. All process steps are repeated until the product has been fully assembled. The last step in the process involves making the connection between the various elements in the silicon. These are so tiny that a minuscule vacuum deposited layer of aluminum is required to make them.
The enumerable processes which take approximately three weeks to complete are concluded by an initial visual inspection. Each chip is checked for several essential functions. After testing chips that do not comply with the specifications are marked. So they’ll no longer be used. Once they have been tested the trips are ready for assembly. First of all, the slices are laid on a layer of adhesive film and then almost sawn through in two directions by a special amazingly accurate soil machine so that the chips are always separated. The slices are then carefully packaged and sent to the assembly centers.
