Rapid thermal processing
From Wikipedia, the free encyclopedia
Rapid Thermal Processing (or RTP) refers to a semiconductor manufacturing process which heats silicon wafers to high temperatures (up to 1200 C or greater) on a timescale of several seconds or less. The wafers must be brought down (temperature) slow enough however, so they do not break due to thermal shock. Such rapid heating rates are attained by high intensity lamps or laser process. These processes are used for a wide variety of applications in semiconductor manufacturing including dopant activation, thermal oxidation, metal reflow and chemical vapor deposition.
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[edit] Temperature Control
One of the key challenges in rapid thermal processing is accurate measurement and control of the wafer temperature. Monitoring the ambient with a thermocouple is not feasible, in that the high temperature ramp rates prevent the wafer from coming to thermal equilibrium with the process chamber. One temperature control strategy involves in situ pyrometry to effect real time control.
[edit] Rapid thermal anneal
Rapid thermal anneal (RTA) is a subset of Rapid Thermal Processing. It is a process used in semiconductor device fabrication which consists of heating a single wafer at a time in order to affect its electrical properties. Unique heat treatments are designed for different effects. Wafers can be heated in order to activate dopants, change film-to-film or film-to-wafer substrate interfaces, densify deposited films, change states of grown films, repair damage from ion implantation, move dopants or drive dopants from one film into another or from a film into the wafer substrate.
Rapid thermal anneals are performed by equipment that heats a single wafer at a time using either lamp based heating, a hot chuck, or a hot plate that a wafer is brought near. Unlike furnace anneals they are short in duration, processing each wafer in several minutes.
