MOVPE

MOVPE (Metal‑Organic Vapor Phase Epitaxy) is a chemical vapor deposition technique used to grow crystalline layers of semiconductor materials on a substrate. In MOVPE, gaseous metal‑organic precursors containing the desired element(s) react in the presence of a carrier gas at high temperature to form a thin film that is epitaxially aligned with the underlying substrate. The temperature, pressure, and flow rates of the gases are carefully controlled to maintain growth rates from a few nanometers per minute to several micrometers per hour. Typical precursors include trimethylgallium and trimethylaluminum for III‑V semiconductors, and organometallic compounds of silicon or group V elements for other compound semiconductors.

The method was developed in the 1960s and 1970s for the production of gallium arsenide and indium phosphide devices, and it has since become the industry standard for fabricating high‑performance light‑emitting diodes, laser diodes, high‑electron‑mobility transistors, and single‑photon sources. MOVPE offers excellent control over dopant concentration, alloy composition, and interface abruptness, making it possible to design complex heterostructures such as quantum wells, superlattices, and graded alloy layers. It also allows the growth of large‑area wafers with high reproducibility, which is essential for mass production.

Key equipment includes a horizontal or vertical reactor tube, a hot wall or cold wall design, T‑cable or on‑tube coaxial supply for the precursors, and a reliable system for temperature monitoring and gas delivery. Safety measures are critical because many metal‑organic compounds are pyrophoric and can decompose violently upon contact with water or dilute acids.

Despite its advantages, MOVPE is limited by the need for expensive precursor chemicals and the requirement for ultra‑clean environments to prevent contamination. However, its flexibility and high crystalline quality continue to make it indispensable in modern semiconductor research and manufacturing.