Controlling the dopant dose in silicon by mixed-monolayer doping

Area of Science:

• Materials Science
• Surface Chemistry
• Semiconductor Physics

Background:

• Molecular monolayer doping (MLD) is an emerging technique for silicon doping.
• It offers a nondestructive approach with potential for ultrashallow junctions and nonplanar surface doping.

Purpose of the Study:

• To investigate the control of dopant concentration in silicon using MLD.
• To explore the mixing of dopant-containing and non-functionalized alkenes for tunable doping.

Main Methods:

• Grafting mixed alkene monolayers onto hydrogen-terminated silicon via hydrosilylation.
• Characterization using contact angle, X-ray photon spectroscopy (XPS), and Auger electron spectroscopy.
• Doping level analysis via dynamic secondary-ion mass spectroscopy (D-SIMS) and Van der Pauw resistance measurements.

Main Results:

• Clear trends in dopant concentration were observed based on alkene ratios.
• Effective tuning of dopant dose in the silicon substrate was achieved.
• Successful control over doping concentration in silicon was demonstrated.

Conclusions:

• Mixing dopant-containing and non-functionalized alkenes allows for precise control over silicon doping via MLD.
• This method provides a viable route for achieving tunable doping for advanced semiconductor applications.