Ultra-Shallow Junction Formation by Plasma doping and Excimer Laser Annealing

Plasma doping (PLAD) process using PH3 plasma is presented to fabricate n+/p ultra shallow junction at room temperature. Directly after the PLAD, a pre-annealing has been conducted for 5 min at 500 degrees C in thermal furnace. ArF excimer laser annealing (ELA) process was then followed with an increment of 20 mJ/cm(2) in the laser energy ranging from 400 to 500 mJ/cm(2). When the laser energy density was larger than 460 mJ/cm(2), a reduced sheet resistance was observed. In order to examine the crystalline defects generated during PLAD, the transmission electron microscopy (TEM) and double crystal X-ray diffraction (DXRD) measurements have been made. With optimized PLAD and ELA conditions, junction depth of 30 nm and sheet resistance of 151.6 Omega/square could be obtained.