Luminescence Studies of Residual Damage in Low-Dose Arsenic Implanted Silicon after High-Temperature Annealing

Abstract

In order to prevent the degradation of device performance, it is necessary to detect and reduce residual damage remaining after ion implantation and annealing. In this study, we focused on the high-temperature annealing process after low-dose arsenic (As) implantation in silicon (Si) and evaluated the correlation of annealing conditions and damage by cathodoluminescence (CL) compared to Secondary Ion Mass Spectrometry (SIMS) and Junction PhotoVoltage (JPV) results. Increasing the annealing temperature with the high-heat-up rate, As profile and the sheet resistance didn't change. However, the intensity of the band-to-band transition increased with temperature. This implies the some kind of residual damage remains after low-temperature annealing and it is removed with increasing annealing temperature. On the other hand, with increasing the annealing time at 1200°C, more As was piled-up at the SiO 2 /Si interface and the luminescence intensity decreased. We guess this piled-up As is inactive and it may create some kind of damage combined with the defects around the interface, and these damage types cause the suppression of the luminescence intensity. We concluded that the luminescence intensity reflects the various kinds of damage and optical characterization methods have a potential to evaluate defect evolution in annealing process.

Thermal Behavior of Residual Defects in Low-Dose Arsenic- and Boron-Implanted Silicon After High-Temperature Rapid Thermal Annealing

“…The TO-line intensity of the only-RTA-applied sample (i.e., additional FA temperature was 0 • C) is clearly much lower than that of the reference sample, suggesting that the TO-line emission had been suppressed by non-radiative decay centers, i.e., some type of defect and/or crystal disorder. This provides strong evidence of the presence of residual damage, as we had discovered in previous studies [2]- [4]. In contrast, the TO-line intensity of the samples with additional FA at 300 • C and 400 • C gradually increased with increased annealing temperature, indicating that the vacancy-type defects mentioned above tended to be eliminated and the total number of defects was suppressed after FA.…”

“…Our previous studies, however, show that use of a rapid thermal process for heat treatment leads to residual damage [2]. In the case of low-dose implant conditions, which is Manuscript lower than the critical dose of amorphization (<10 13 cm −2 ), defects were confirmed to persist after applying RTA even with high-temperature (1100 • C) [3], [4].…”

Detection and characterization of residual damage in low-dose arsenic implanted silicon after high-temperature annealing

“…c-o complex, which is origin of C-line emission as to be inversely proportional to electron conductivity (J and junction depth X j [2]. Tn order to separate these elements and confirm the reason of this phenomenon, As and B depth profiles of all samples were measured and the junction depth were evaluated from their profiles.…”

“…implanted Si after high-temperature rapid thermal annealing (RTA) by using optical characterization method, cathodoluminescence (CL), and this damage has been confIrmed to be a non-radiative decay center [2]. Moreover, our recent studies have been revealed that residual damage changes their feature according to the atmosphere during annealing.…”