Specific Process Knowledge/Thermal Process/Dope with Boron: Difference between revisions

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-==Dope with boron==
+==Doping with boron==
-The furnace A1 Boron Drive-in and Pre-dep can be used to pre-deposit silicon wafers with boron. The silicon wafers are positioned in a silicon carbide boat just next to wafers of boron nitride. Pre-deposit of boron is a diffusion process on the silicon wafers.
-The concentration of boron in the wafer depends on the process temperature.
+The Boron Drive-in and Pre-dep furnace (A1) can be used to pre-deposit silicon wafers with boron.
-The depth profile depends of the process time.
+The boron doping is done by use of boron silicate source wafers, that allows boron to diffuse into the silicon wafers. These have to be RCA1 cleaned activated, i.e. heated up to at least 1050 <sub>C<\sub>, before the boron pre-deposition is done.
+In the furnace, the silicon wafers are positioned in a silicon carbide boat just next to the boron nitride source wafers. The side of the silicon wafers that should be doped, has to point towards the source wafers.
+The concentration of boron in the wafer depends on the process temperature, and the doping depth profile depends of the process time.
 All this figures have been made at the time where there was a furnace only for Boron Pre-dep (furnace A2). The process was done at a temperature of 1125 <sup>o</sup>C and a flow of 5 slm N<sub>2</sub> and 0.2 slm of O<sub>2</sub>.