Decontamination Services And the Semiconductor Wafer:

The decontamination of various pieces of equipment has becoming increasingly important over the past few decades. When handled correctly, it can actually have a positive impact upon the environment. By reducing waste through recycling and preventing exposure to the rest of the working or other types of environment, decontamination services can ensure older components of equipment are recycled. The process can help prepare the material for any of the five “Rs”:

1. Reuse
2. Resale
3. Repair
4. Refurbishment
5. Relocation

This is obviously a factor in decontaminating a semiconductor component known as a “wafer.”

What Is a Semiconductor Wafer?

A semiconductor wafer is a piece of silicon created in a round shape. First manufactured in the United States in 1960, it has since grown to be a popular component of many electronic devices.

They are available in one of two basic types:

1. Application-specific integrated circuit (ASIC)
2. Integrated circuit (IC)

The former type of circuit is a form customized for a specific purpose; the latter is intended for general use. Wafers, as a result, come in many different diameters. Currently they measure up to 12 inches in diameter. They are expected to increase up to 18 inches in the future. However, while they may expand in this direction, companies and fabricators are also looking at making them thinner to produce ultra-thin wafers for devices.

Five Grades of Wafers

Wafers come in different grades. These range from the highest quality wafers to those less expensive.

1. Prime: This is the highest grade possible of silicon wafers. The best tend to be prized for their smoothness, flatness and defect free.
2. Test: As the name indicates, this is a less than perfect silicon wafer used for testing purposes only e.g. process monitoring.
3. Reclaimed: This is a previously used wafer reclaimed through decontamination services and put back to work following refinishing to at least test grade quality.
4. Recycled: Cleaning of a wafer using only specific surface treatment processes, produces one suitable for reprocessing
5. Epi: This is a less expensive alternative to prime wafers. It features a slim layer of N- silicon developed on the surface of a Boron wafer.

Decontamination Services

Decontamination approaches will vary according to the level of contamination and other factors. It is essential, first to identify the actual source of the contamination before proceeding. Once recognized, the fabricator can employ the proper method producing viable wafers for reuse. Decontamination services are capable of returning the wafers back into use. Two common grades of semiconductor wafers resulting from the decontamination process are reclaimed wafers and recycled wafers.