Electrical Properties of New Nitride Semiconductors

1
Electrical Properties of New Nitride
Semiconductors
Mark E. Little Physics and Engineering little_at_hope
.edu [phone]
Sample preparation Thin films of nitride
semiconductors are prepared by reactive
magnetron sputter-deposition as shown below.
Photograph
Education and experiences Ph.D., Condensed Matter
Physics, Ohio University (2001) B.S., Physics,
Ohio University (1995) HopeCollege, Assistant
Professor (2002-) ICASE,NASA Langley Research
Center, Staff Scientist (2001-2002)
Motivation New nitride materials such as ScN
have little known about their electrical propertie
s. We prepare thin film samples of III-nitride
materials and investigate their
electrical conduction properties. Conduction in
semiconductors is by the motion of electrons in
the conduction band or by holes in the valence
band. By carefully measuring the electrical
current in the films the number, type, and
mobility for each carrier type are determined
by The methods shown below.
Areas of expertise Solid sate and condensed
matter physics. III-Nitride semi-conducting thin
films
Grants and awards NSF-PHY 0452206, REU at Hope
College (300,867)(2004) Research Corporation,
Cottrell College Science Award CC5962, Charge
carrier transport investigations in amorphous
nitride films using time-of flight drift mobility
(46,048)(2003)
Hall Effect A standard technique used to
measure the majority carrier Type, mobility, and
concentration by Measuring the voltage VH.

• Drift Mobility Used to
• measure the minority carrier
• properties. An injecting pulse
• (either electrical or optical) is
• supplied at point E. Current
• signals are recorded at point C.
• By knowing the time-of-flight
• and the distance between the
• injection and collection points
• the mobility of the minority
• carriers is found.

Key publications and presentations Sang H. Choi
and Mark Little, Field-sensitive materials for
optical application, AIAA Nanotech 2002
proceedings, AIAA Paper 2002-5747 (2002) M.E.
Little and M.E. Kordesch, Bandgap engineering in
amorphous/microcrystalline ScxGa1-xN, Mat. REs.
Soc Symp. Proc. (Fall 2002) M.E. Little and M.E.
Kordesch, Bandgap engineering in
sputter-deposited Scx-xN, Appl. Phys. Lett. 79,
2891 (2001) Electrical Conductivity measurements
of sputter-deposited ScN thin films, Materials
Research Society Symposium (accepted for
presentation Fall 2005)
Acknowledgements