China high purity graphite Manufacturers, Suppliers, Factory

Semiconductors are materials whose electrical conductivity at room temperature lies between that of insulators and conductors. By introducing impurities, a process known as doping, these materials can become conductors.

The tray (base) that supports SiC wafers, also known as a "susceptor," is a core component of semiconductor manufacturing equipment. And what exactly is this susceptor that carries the wafers?

Graphite susceptor is one of the essential parts in the MOCVD equipment, is the carrier and the heater of the wafer substrate. Its properties of thermal stability and thermal uniformity play a decisive role in the quality of wafer epitaxial growth, which directly determines the uniformity and purity of the layer materials, in a result its quality directly affects the preparation of epitaxy.

The wafer boats, loaded with a batch of wafers to be processed, are positioned on long cantilevered paddles.

Defect-free epitaxial growth occurs when one crystal lattice has nearly identical lattice constants to another. Growth happens when lattice sites of the two lattices at the interface region are approximately matched, which is possible with a small lattice mismatch (less than 0.1%). This approximate matching is achieved even with elastic strain at the interface, where each atom is slightly displaced from its original position in the boundary layer. While a small amount of strain is tolerable for thin layers and even desirable for quantum well lasers, the strain energy stored in the crystal is generally lowered by the formation of misfit dislocations, which involve a missing row of atoms in one lattice.

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.