The semiconductor industry manufactures integrated circuits in large vacuum chambers where the pressure is 1.0×10^−10 mm of Hg. a. What fraction is this of atmospheric pressure?

Key Concepts

Atmospheric Pressure

Atmospheric pressure is the force exerted by the weight of air above a given point, typically measured at sea level. Standard atmospheric pressure is defined as 1013.25 hPa (hectopascals) or 760 mm of Hg (millimeters of mercury). Understanding this concept is crucial for comparing other pressures, such as those in vacuum chambers, to the baseline atmospheric pressure.

Vacuum Pressure

Vacuum pressure refers to the pressure in a system that is lower than the atmospheric pressure. It is often measured in units such as mm of Hg or pascals. In the context of the semiconductor industry, achieving a vacuum of 1.0×10^−10 mm of Hg indicates an extremely low pressure, which is essential for processes like deposition and etching in integrated circuit manufacturing.

Pressure Ratio

The pressure ratio is the comparison of two pressures, typically expressed as a fraction or percentage. To find the fraction of a specific pressure relative to atmospheric pressure, one divides the given pressure by the standard atmospheric pressure. This concept is important for understanding how much lower the vacuum pressure is compared to normal atmospheric conditions, which can impact various physical processes.