Introducing the Deposition Process for Semiconductors and Precursors

Semiconductors are circuit chips developed on wafers where countless transistors and electronic materials are constructed to produce the microscopic miracles known as semiconductors. Mainstream semiconductor technology has ranged from 30 nanometers (1nm = one billionth of a meter) and is currently in the development process for 10nm. Precursor metals are organic compounds with ligand bonds that create thin films and are deposited onto the semiconductors as a coating or sacrificial layer throughout the manufacturing process.

Today we will introduce the basics of deposition.

There are typically two types of deposition methods known in the industry as ALD and CVD. The biggest differences between CVD and ALD are the thickness of each layer, time it takes to coat, and the method of injecting the gases into the chamber.

Chemical Vapor Deposition (CVD) creates thin films through a chemical reaction between two gases in an enclosed chamber. There are a variety of processes within CVD that differs depending on the amount of pressure and heat used in the chamber to create a reaction. One representative approach is Plasma Enhanced Chemical Vapor Deposition or PECVD, where precursors are injected into a negatively charged vacuum chamber that serves as an ideal electric field for chemical reactions. As the gas molecules react with each other, a thin film is deposited onto the semiconductor to execute its designed task.

Atomic Layer Deposition (ALD) is a process used for detailed applications. As the name states, every ALD cycle deposits a single atomic layer of film at a time. ALD requires more time than CVD because of its atomic scale and delicate process. ALD also differs from CVD in that there is no chemical reaction that results in deposition. ALD comprises of four steps of depositing and purging gases separately to create each film layer.

Hansol Chemical Precursors are compatible with both CVD and ALD methods and continue to lead the way in preparation for the next generation of thin film technology.