Thermal annealing induced photocarrier radiometry enhancement for ion implanted silicon wafers

Abstract

An experimental study on the photocarrier radiometry signals of As + ion implanted silicon wafers before and after rapid thermal annealing is performed. The dependences of photocarrier radiometry amplitude on ion implantation dose (1×10 11 -1×10 16 /cm 2 ), implantation energy (20-140 keV) and subsequent isochronical annealing temperature (500-1100 • C are investigated. The results show that photocarrier radiometry signals are greatly enhanced for implanted samples annealed at high temperature, especially for those with a high implantation dose. The reduced surface recombination rate resulting from a high built-in electric field generated by annealing-activated impurities in the pn junction is believed to be responsible for the photocarrier radiometry signal enhancement. Photocarrier radiometry is contactless and can therefore be used as an effective in-line tool for the thermal annealing process monitoring of the ion-implanted wafers in semiconductor industries.

Depth profile reconstructions of electronic transport properties in H+ MeV-energy ion-implanted n-Si wafers using photocarrier radiometry

“…INTRODUCTION Accurate control and evaluation of the electronic properties of ion implanted semiconductors have been an important issue in the electronics industry. [1][2][3] During the ion implantation process, semiconductors are electronically compromised due to the interaction of implanted ions and the crystalline structure, which forms an inhomogeneous structure with depth-varying subsurface electronic properties. To investigate the properties of the ion-implanted samples, photothermal radiometry (PTR) has been used to characterize the electronic behavior via infrared thermal photon emission which is related to non-radiative de-excitation processes.…”