Dependence of ion implantation: Induced defects on substrate doping

Abstract

The characteristics of an ion implantation-induced defect in a silicon substrate are investigated. This defect is considered to be a complex of a point defect and a substrate dopant atom. The experiments are conducted by focusing on the dependence of the substrate dopant species (phosphorus and boron) on defect formation. The characteristics of the defect are investigated by measuring the bulk generation lifetime (τg) of metal–oxide–semiconductor capacitors, in which Si+ has been implanted to form the dopant-related defects in the substrate (damaging implantation) after gate oxide formation. As a result, it is found that the τg of the boron-doped substrate is one to two orders of magnitude smaller than that of the phosphorus-doped substrate for the same Nsub under the same implantation conditions. The temperature dependence of τg shows that the energy level of the defect is located at the intrinsic Fermi level, independent of the substrate dopant species and the concentration. By measuring the dependence of τg on the temperature of postdamaging implantation annealing, it is shown that the defects vanish at about 800 °C for both types of substrate. Also, it is found that the amount of dopant-related defects depends on the implantation ion species. BF2+ implantation forms more defects than As+ implantation.

Optically Controlled Silicon MESFET Fabrication and Characterizations for Optical Modulator/Demodulator

“…Experiments measuring the bulk generation lifetime of MOS capacitors have shown residual ion implantation defects in the substrates remain in spite of annealing [19]. Phosphorus ion implantation not only results in the transition of the crystalline fullerenes to an amorphous material phase, but also produces a significant defect level, which is evident from solar cell efficiency ranges of only 10-20% [20].…”

“…Ion implantation induced defects in silicon substrates have been characterized to study the dependence of substrate dopant species (phosphorous and boron) on defect formations [29]. I-V characteristics of ion implanted solar cell devices at optical illumination have shown efficiencies as low as 0.01%.…”

“…4 shows the impurity distribution of KOH etched sample extracted from C-V measurement, where the KOH etching brings the surface concentration down from about 2x10 19 cm -3 to the range of 6x10 16 -7x10 16 cm -3 and the junction depth in the range of about 0.1 µm. The source and drain doping was formed by diffusion process using PH900 and the drain/source doping con- centration and junction depth were kept in the range of 5x10 19 -8x10 19 cm -3 and 0.5 to 0.75 µm. Aluminum film deposition for source/drain was performed by a sputtering system with power set to 100 Watt and 10SCCM argon flow resulting in the chamber pressure of approximately 4.3x10 -3 Torr for 30 minutes.…”

Optically Controlled Silicon MESFET Modeling Considering Diffusion Process

“…The ion implantation induced defects in a silicon substrate have been characterized by measuring the bulk generation lifetime of MOS capacitor and experiments have been conducted to study the dependence of substrate dopant species (phosphorous and boron) on defect formations [17]. I-V characteristics of ion implanted solar cell devices at optical illumination have shown the efficiency in the range of 0.01%.…”

Low Leakage Current and Low Resistivity p+n Diodes on Si(110) Fabricated by Ga+ and B+ Dual Ion Implantation for Low Temperature Source–Drain Activation

“…The principle of source-drain activation by low temperature annealing is a solid phase epitaxial regrowth (SPER) of the amorphous layer fabricated by the ion implantation. [5][6][7][8][9][10] Furthermore, the improvement of metal-oxide-semiconductor field-emission transistors (MOSFETs) current drivability without shrinking is also important in order to improve LSI performance. It has been shown that the current drivability of MOSFET is vastly improved by making the device on Si(110) surface.…”