Understanding and controlling transient enhanced dopant diffusion in silicon

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:375954

Stolk, P A; Gossmann, H J; Eaglesham, D J; Jacobson, D C; Poate, J M ^[1]; Luftman, H S ^[2]

---

1. AT and T Bell Labs., Murray Hill, NJ (United States)
2. AT and T Bell Labs., Breinigsville, PA (United States)

Implanted B and P dopants in Si exhibit transient enhanced diffusion (TED) during initial annealing which arises from the excess interstitials generated by the implant. In order to study the mechanisms of TED, the authors have used B doping marker layers in Si to probe the injection of interstitials from near-surface, non-amorphizing Si implants during annealing. The in-diffusion of interstitials is limited by trapping at impurities and has an activation energy of {approximately}3.5 eV. Substitutional C is the dominant trapping center with a binding energy of 2--2.5 eV. The high interstitial supersaturation adjacent to the implant damage drives substitutional B into metastable clusters at concentrations below the B solid solubility limit. Transmission electron microscopy shows that the interstitials driving TED are emitted from {l_brace}311{r_brace} defect clusters in the damage region at a rate which also exhibits an activation energy of 3.6 eV. The population of excess interstitials is strongly reduced by incorporating substitutional C in Si to levels of {approximately}10{sup 19}/cm{sup 3} prior to ion implantation. This provides a promising method for suppressing TED, thus enabling shallow junction formation in future Si devices through dopant implantation.

• OSTI ID: 375954
• Report Number(s): CONF-941144--; ISBN 1-55899-255-3
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING
ATOM TRANSPORT
BORON
CRYSTAL DOPING
DIFFUSION
INTERSTITIALS
ION IMPLANTATION
PHYSICAL RADIATION EFFECTS
SEMICONDUCTOR DEVICES
SILICON