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We know that further epitaxial layers need to be built on top of some wafer substrates for device fabrication, typically LED light-emitting devices, which require GaAs epitaxial layers on top of silicon substrates; SiC epitaxial layers are grown on top of conductive SiC substrates for building devices such as SBDs, MOSFETs, etc. for high voltage, high current and other power applications; GaN epitaxial layers are built on top of semi-insulating SiC substrates for building HEMTs and other RF applications.

In semiconductor manufacturing, the precision and stability of the etching process are paramount. One critical factor in achieving high-quality etching is ensuring that wafers are perfectly flat on the tray during the process. Any deviation can lead to uneven ion bombardment, causing undesirable angles and variations in etching rates. To address these challenges, engineers have developed Electrostatic Chucks (ESCs), which have significantly improved etching quality and stability. This article delves into the design and functionality of ESCs, focusing on one key aspect: the electrostatic principles behind wafer adhesion.

In the process of growing SiC and AlN single crystals by the physical vapor transport method (PVT), components such as the crucible, seed crystal holder and guide ring play a vital role. During the preparation process of SiC, the seed crystal is located in a relatively low temperature region, while the raw material is in a high temperature region exceeding 2400°C. The raw materials decompose at high temperatures to form SiXCy (including Si, SiC₂, Si₂C and other components).

The coated parts in semiconductor silicon single crystal hot field are generally coated by CVD method, including pyrolytic carbon coating, Silicon Carbide coating and Tantalum Carbide coating, each with different characteristics.

SiC substrate can have microscopic defects, such as Threading Screw Dislocation (TSD), Threading Edge Dislocation (TED), Base Plane Dislocation (BPD), and others. These defects are caused by deviations in the arrangement of atoms at the atomic level. SiC crystals may also have macroscopic dislocations, like Si or C inclusions, micropipe, hexagonal voids, polymorphs, etc. These dislocations are typically large in size.

Specialty graphite is graphite with carbon mass fraction greater than 99.99%, also known as "three high graphite" (high strength, high density, high purity). It is characterized by high strength, high density, high purity, high chemical stability, high thermal and electrical conductivity, high temperature resistance, radiation resistance, strong lubrication and easy processing. Isostatic graphite belongs to specialty graphite.