Investigation of Ion Implantation Damage with Stress Measurements

Abstract

The stress set up lateral to the implanted surface by ion implantation lattice damage is measured for 220 keV ⁴He, ¹²C, ¹⁶O, ²⁰Ne, ²⁷Al, ⁴⁰Ar, ⁸⁴Kr, and Xe room temperature implants into Si. It is found that the ions with atomic number greater than Si produce more damage per given energy density deposited into atomic processes E than the lighter ions and produce damage almost linearly with E up to a distinct maximum in the stress. The measurements from ⁴He, ¹²C, ¹⁶O, ²⁰Ne, ²⁷Al implants are indistinguishable from one another at low E values where the damage depends linearly upon E. These lighter ions introduce damage sublinearly with E at medium E values. The maximum in all the stress versus E results is taken as evidence for an elastic-plastic transition in the implanted layer. This elastic-plastic transition is correlated with what others have called the crystalline-to-amorphous transition.

This work was supported by the U.S. Atomic Energy Commission.