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MOCVD technique was introduced by H.M. Manaserti in 1968 and becoming more popular after 1970’s. This method was used in production of devices, such as lasers, photocathode, photo detector, light emitting diodes (LED) and many more. One of the advantages of this method is the ability in producing a large scale product. Several other advantages of this process including potential for large area growth, good film conformity ad composition control, high film densities, high deposition rate, and excellent conformal step coverage at dimensions less than 2 μm.

Metalorganic Chemical Vapor Deposition is a type of the Chemical Vapor Deposition (CVD) to produce the thin layers of atom onto a substrate such as semiconductors wafer. The term metalorganic itself describe the use of metalorganic compound as the starting material in the prosses. Beside that the hydrides compound is also use as the precursor.

The basic principle of MOCVD is the transport of precursor molecules that is the organometallic constituents by a carrier gas, usually hydrogen or nitrogen or mixture of the two, onto a heated substrate. The complex will passed over a hot substrate wafer, which the heat will breaks up molecules and deposits the desired atoms on the surface of the substrate. Generally the MOCVD system is divided into three major compartments:

i. Reactor gas delivery.
- This is the part where the precursor vapor and the carrier gas is control.
- Basically there are two types of the delivery modules that are the hydride delivery module and alkyl or the metalorganic delivery modules. One of the reason of the differentiation is because the form of the precursor. Hydride most of the time is in the form of gas while metalorganic precursor is in the form of liquid (exception such as TMIn that is solid).

ii. Reaction chamber
- This is the part where the source gases are mixed and introduced to the heated zone where the substrate is located. There are two basic types of the reaction chamber that is vertical reaction chamber and horizontal reaction chamber. In vertical reaction chamber, the interest vapor enters from the top to the substrate on the rotating susceptor plate. While in the horizontal reaction chamber, the vapor enters laterally to the substrate.

iii. Reactor safety infrastructure/ Exhaust system
- It composed of:
i. Pump and pressure controller to control the growth pressure.
ii. Waste gas treatment system. Some of the precursor did not react and contain a toxic gas. This exhaust gas must be treating properly in them matter of safety concern.

References:
Coleman J.J. 1997. Metalorganic chemical vapor deposition for optoelectronic devices. Proceedings of the IEEE, 85.11. 1715–1729.
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