core equipment for thin film deposition in semiconductor manufacturing

The chemical vapor deposition (CVD) furnace is a core equipment for thin film deposition in semiconductor manufacturing. Its fundamental principle involves inducing chemical reactions of gaseous precursors on a heated substrate surface to form and deposit solid thin films. To clarify, multiple branches exist within chemical vapor deposition, commonly referred to as CVD. Depending on reaction conditions, various technical branches have been derived, including atmospheric pressure CVD (APCVD), low-pressure CVD (LPCVD), plasma-enhanced CVD (PECVD), and atomic layer deposition (ALD) for advanced processes. Taking the widely used LPCVD as an example, it operates under vacuum conditions below 0.1 MPa, where the increased mean free path of gas molecules significantly improves film uniformity and step coverage, with typical working temperatures ranging between 425°C and 900°C. In contrast, PECVD utilizes plasma enhancement to substantially reduce reaction temperatures to 200-400°C, preventing high-temperature damage to devices. Collectively, these systems form the technological foundation for semiconductor thin film material preparation.

In the semiconductor chip manufacturing process, CVD technology is used to deposit various key thin-film materials. Specifically, a wide range of methods like chemical vapor deposition (CVD) are employed for polycrystalline silicon, silicon nitride, and barrier layers. Specific applications include: polycrystalline silicon films for gates and capacitors, silicon nitride (Si₃N₄) and silicon oxide (SiO₂) films for device isolation and passivation layers, as well as barrier layers (such as titanium nitride TiN) and conductive layers (such as tungsten) for metal interconnects. Additionally, CVD furnaces play a particularly prominent role in the third-generation semiconductor field, such as in the high-quality homoepitaxial growth of silicon carbide (SiC) power devices, and in the growth of large-size, low-defect SiC single-crystal substrates using high-temperature chemical vapor deposition (HTCVD) at 2100~2300°C. This technology is also widely used in preparing epitaxial layers of compound semiconductors (such as GaN, GaAs) required for LEDs and RF devices.

Currently, as semiconductor device structures evolve toward 3D and miniaturization, CVD technology faces higher demands. Moreover, the adoption of advanced manufacturing processes often relies on the precision of Chemical Vapor Deposition (CVD) systems for atomic-level control. ALD technology has become indispensable in manufacturing high-aspect-ratio structures (such as 3D NAND memory chips) due to its precise atomic-level control and excellent three-dimensional conformality. From an industrial perspective, CVD equipment is advancing toward higher purity, better uniformity, and greater production capacity. Chinese enterprises and research institutions have made significant breakthroughs in key technological areas, such as successfully developing silicon carbide CVD equipment with coating purity no less than 99.9999% and commercial APCVD equipment with film thickness uniformity controlled within 2%, achieving industry-leading technical specifications and strongly advancing the localization of high-end semiconductor equipment.