As wafer structures in semiconductor manufacturing become more complex, the significance of wafer wet cleaning processes is on the rise. Cleanliness is crucial in semiconductor fabrication to guarantee the quality and performance of the final devices. Defects in devices and reduced performance can be caused by contaminants such as organic residues, metals, and particles.

Ozone has gained popularity in wet cleaning and photoresist removal methods due to its high reactivity, which quickly and effectively breaks down organic compounds. Furthermore, ozone is considered relatively safe because it converts back to oxygen after reacting with contaminants. Compared to RCA cleaning techniques, ozone/water cleaning processes are more cost-effective and environmentally friendly. Ozone is no longer solely of scientific interest in semiconductor applications, as it can offer practical advantages in the manufacturing processes of wafers and ICs.

Ozone has gained popularity in the semiconductor cleaning industry due to its environmentally friendly nature. It offers several advantages such as reducing water consumption and eliminating the need for expensive chemical products. Ozonated water can also effectively remove photoresist and eliminate metal and particulate contamination in the industry.

ALD processes can use ozone instead of traditional precursors like halogens or hydrogen peroxide. When used in ALD, ozone oxidizes the substrate surface to facilitate the deposition of high-quality and conformal films with precise thicknesses. Ozone is an exceptionally reactive species that can penetrate small spaces, making it perfect for depositing thin films on high aspect ratio structures. Moreover, due to its outstanding oxidizing capabilities, it is ideal for depositing oxide films. One of the major benefits of using ozone in ALD is the reduction in process steps, leading to increased efficiency, faster deposition times, lower precursor usage, and less material waste.

Introduction of Ozone and Its Function in Semiconductors

Ozone gas is a highly reactive substance that can efficiently decompose a diverse range of pollutants. It finds its application in the semiconductor industry, where it is utilized to eliminate pollutants from silicon wafer surfaces via exposure to an ozone-based cleaning solution. The ozone in the cleaning solution reacts with pollutants, breaking them down and leaving the surface devoid of impurities.

Benefits of Using Ozone in Semiconductor Manufacturing

1. Ozone is a highly effective cleaning agent, capable of rapidly and thoroughly eliminating a broad range of contaminants, including organic residues, metals, and particles. As such, it is an excellent option for cleaning semiconductor surfaces to uphold a superior level of cleanliness.

2. Ozone is an environmentally friendly option for cleaning semiconductor surfaces as it is a naturally occurring gas that swiftly converts back to oxygen after reacting with contaminants. This sets it apart from other cleaning agents that may have harmful chemicals.

3. Ozone is a rapid and efficient cleaning agent that swiftly eliminates surface contaminants. Therefore, it is an ideal choice for time-sensitive cleaning processes that require quick and effective results.

4. Ozone is a versatile cleaning agent that can be applied in different ways, such as surface cleaning, water treatment, and air purification. This adaptability makes it a suitable choice for various industries that require different cleaning applications.

5. Ozone is generally considered safe for both workers and the environment when used correctly.

The Use of Ozone for ALD Deposition

Atomic Layer Deposition (ALD) is a precise thin-film deposition technique that allows for exact control over film thickness. ALD is used in a variety of industries, including semiconductor, energy storage, biomedical, optics, and other high-tech fields. This technology involves the controlled growth of ultra-thin films on a substrate surface through sequential chemical reactions on an atomic scale, resulting in highly precise and controlled molecular layer deposition.

ALD operates by alternating the substrate's exposure to one or more gaseous precursors, each designed to selectively react with the substrate and form a specific chemical bond. The excess precursor is then removed after each exposure, leaving a monolayer of the desired material on the substrate. This process is repeated until the desired thin film thickness is achieved, making ALD suitable for depositing high-quality films on complex structures with high aspect ratios. ALD's precise control over film thickness and composition makes it ideal for semiconductor applications where high uniformity and precision are essential.

Ozone is a favored oxidizer in ALD due to its numerous benefits. Its high reactivity enables it to react quickly and effectively with precursors, resulting in faster film growth and improved efficiency, which can save time and money.

Benefits of Using Ozone in ALD process

1. The use of ozone in ALD enables precise control over the thickness of thin films while maintaining high-quality films. Ozone provides uniform thickness and well-defined crystal structures, which results in improved surface coverage. These characteristics make it a preferred option for applications that require high-quality films with specific material properties. Such films can lead to improved performance, increased reliability, and reduced risk of product failure.

2. ALD using ozone allows for the deposition of a wide range of materials including metals, oxides, and nitrides. This versatility makes ozone an ideal tool for advanced manufacturing as it enables manufacturers to produce a variety of products with different material properties using a single deposition process, thereby reducing the need for multiple processes and equipment.

3. Ozone reactions in ALD occur at low temperatures, making it a suitable choice for temperature-sensitive substrates. The advantage of a low-temperature process is the reduced risk of substrate damage or degradation, leading to improved thermal ALD processing.

4. Cost-effective: Ozone is a cost-effective reactant, which makes it an attractive option for ALD processes. It can be particularly useful for depositing thin films on temperature-sensitive substrates such as flexible electronics, bio-implants, or optical fibers, which can be damaged or degraded when exposed to high temperatures during deposition processes. By using ozone in ALD, manufacturers can avoid these issues and produce high-quality films without causing damage to the substrate, ultimately leading to cost savings.

To summarize, ozone can enhance the efficiency and quality of your atomic layer process due to its high reactivity, surface-penetrating ability, and environmental friendliness. Therefore, it is a suitable option for various applications. If you aim to improve efficiency and quality, switching to ozone as your oxidizer could be a favorable option.