Stress-induced alignment experiments [236,237], primarily on TD3, show that the defects can reorient with a barrier of 2.70.2eV, likely to be through interstitial oxygen motion. The time constant is however 5 times longer than that of isolated interstitial oxygen, suggesting that reorientation time is limited by 5 Oi hops. It was shown with IR that this time constant increases with higher order TDs .
Analysis of the NL8 alignment gives the average effective C2v strain coupling tensors shown in Table 9.1. This means the defect must be compressive along 001 , tensile along 110 , and weakly tensile along 110 . IR excitation spectra were used to show that the B3 coupling coefficient dropped off with increasing TD+ species .
|3cAverage effective strain coupling tensor||Anneal Time||Primary Thermal Donor|