Annealing characteristics and electrical properties of 1-MeV arsenic-ion-implanted layers in silicon

Abstract

Arsenic ions have been implanted in (100)Si at an incident energy of 1 MeV to a dose of 1×1015/cm2. Rutherford backscattering measurements with a 1.5-MeV He-ion beam have shown that a buried amorphous layer is formed in the Si substrate which is implanted at a low ion-beam current of 0.8 μA and that considerable annealing occurs when implantation is carried out at a high ion-beam current of 2 μA. The implantation-induced amorphous layer recrystallizes after annealing above 550 °C, but a high density of lattice defects still remains in the substrate even after annealing at 1000 °C. Defect observations using a cross-sectional transmission electron microscope have revealed that those defects are located at the two depths corresponding to the initial transition regions where the crystallinity is changed from the amorphous to nonamorphized states in the substrate. In addition, secondary defects also exist in a particular region inside the initial buried amorphous layer. The recrystallization of the buried amorphous layer during post-implant annealing is initiated not only from the deeper part of the substrate but also from the nonamorphized surface layer. From a series of isothermal annealing studies, it has been shown that the recrystallization rates at 550 °C are 140 and 180 Å/min on the frontside and backside of the buried amorphous layer, respectively. Electrical profile measurements, using the differential Hall method, have shown that a highly doped, buried conductive layer with a peak carrier concentration of around 2×1019/cm3 can be formed by annealing above 800 °C.

Optical response of free-carrier plasma effects of MeV arsenic-ion-implanted silicon

“…1. The 0 1 2 3 4 5 6 full curve in Fig. 2a is the result of the fitting of the reflection spectrum using the theoretical model.…”

“…At present, one of the most important applications of high energy implantation in Si is the formation of a highly doped, buried conductive layer. The microstructure and electrical properties of buried conductive layers formed by 1 MeV As ion implantation were studied by using Rutherford backscattering (RBS), transmission electron microscopy (TEM), secondary ion mass spectroscopy (SIMS), and differential Hall measurements [3]. However, there are no reports on the optical properties of buried conductive layers formed by MeV ion implantation.…”

Ion Implantation in β ‐ SiC Layers Grown on (100)Si

“…Layer-by-layer recrystallization minimizes the presence of residual defects in the substrate after annealing. 15 As previously described, the SiC used in this work was not a perfect single crystal and the interface was not well defined in the substrate. Therefore, the recrystallization of the amorphous layer proceeded along random directions resulting in the presence of a large number of residual defects in annealed room temperature samples.…”

Indirect optical crosstalk reduction by highly-doped backside layer in single-photon avalanche diode arrays

“…2c, which was processed in an n-type substrate, the crosstalk-reduction layer is implemented as an ion-implanted Si layer doped with arsenic (As). Such layers are possible to fabricate using standard CMOS-compatible ion implantation process, as shown in Tsukamoto et al (1980), Inada et al (1990) and Claudio et al (2002).…”