The impression that I have gotten from the latest magazines and websites about microchips is that the chip is definitely the mile stone in computer hardware. Computer chips make up our everyday lives enabling many of the things we use like coffee machines, microwaves, ATMs, and computers work and are reliable for use. These chips are no larger than a fingernail and are getting smaller every other year and are amazingly capable of holding over 1.5 million transistors. The computer chipís history is very short and many of us (including myself) do not remember a time when we were without integrated circuits. The things that we do remember are the advances and theories major companies, Professors, and engineers discover.

The first computers used components called vacuum tubes. These vacuum tubes functioned as electronic switches. The tubes worked fine except that they were not reliable. Because of the big structure vacuum tubes would generate intense heat, which caused many of the components to deteriorate, and consumed enormous amounts of power. A smaller flow of electrons was sought after, and what they found were transistors. Transistors changed the way computers could and would be built.

The integrated circuit was invented by Jack Kilby, an engineer at Texas Instruments, and independently by Robert Noyce of Fair Child Semi-conductor. Then integrated circuit, or chip, combined multiple transistors into a small silicon disc. This silicon chip was the backbone of the development of smaller systems.

Computer chips have a phenomenal rate of performance over time and was considered as a revolutionary device. According to Mooreís Law: The number of components in a single chip doubles every two years. Computers have since become cheaper and their capabilities have increased exponentially over time.

HOW IS A COMPUTER CHIP MADE?

A Computer chip is a tiny piece of material, that contains a complex electronic circuit and are made by placing and removing thin layers of insulating conducting and semi-conducting materials in hundreds of steps. The bodies of most chips are made of silicon and are used because silicon is a semi-conductor.

Clean rooms are special laboratories where a lot of the manufacturing process is performed. The components of a chip are so small that the tiniest dust particle could ruin a chip. These clean rooms are very sterile and are one thousand times cleaner than hospitals. People who work in these laboratories are required to wear bunny suits and use an air shower to remove any dust form the suits before entering these rooms.

The first step in the manufacturing process involves melting the silicon crystals. After these crystals have reached its melting point seed crystals are carefully dipped into the melted silicon to form a cylindrical ingot five to ten inches in diameter and several feet long. This long ingot is then smoothed and cut into wafers. The manufacturing of these wafers can take from ten to thirty days. Each wafer forms the foundation for hundreds of chips. Engineers use a computer-aided circuit design program to design each layer of the chip. Depending on the amount of layers a chip may take a month to several work years to complete.

A robot because of the use of dangerous chemicals does the next step. The robot polishes, sterilizes, and cleans the silicon wafer in a chemical bath. The wafers are then placed in a diffusion oven where they are coated with photo resist.

After the photo resist is applied, the wafers are put through a process called photolithography which patterns almost every layer into the shape of specific electronic components. An Ultra violet light projected through the glass mask prints each layers circuit pattern on the photo resist.

The photo resist that is exposed to the light becomes hard while the photo resist covered by the chip remains soft. Channels in these layers of materials are then etched off. The soft photo resist and some of the surface materials are etched away with hot gases, leaving circuit pathways. This step is repeated with each layer of the chip.

Manufacturers add certain impurities to the silicon chips like Boron and Phosphorus to enable the chips to conduct electricity at room temperature. The doped regions form the electronic components, which will be able to conduct electricity. Some chips contain millions of components. Manufacturers create thin lines of metal (usually aluminum) to