Impact of Electrical Contacting Scheme on Performance of InGaN/GaN Schottky Solar Cells

Realization of low-resistance electrical contacts on both sides of a solar cell is essential for obtaining the best possible performance. A key component of a solar cell is a metal contact on the illuminated side of the cell which should efficiently collect carriers. These contacts can be formed using an opaque metal grid/finger pattern. The metal electrode may be used alone or in combination with a broad-area transparent conductive film. This work aims at investigating the impact of the electrical contacting scheme employed in InGaN/GaN Schottky barrier solar cells on their performance. InGaN is a III-V compound semiconductor and has a tunable direct band-gap (0.7 eV to 3.4 eV) which spans most of the solar spectrum; this fact, along with other beneficial material properties, motivates the study of InGaN photovoltaic devices. A number of groups have recently investigated InGaN-based homo-junction and hetero-junction p-i-n solar cells. However, very few groups have worked on InGaN Schottky solar cells. Compared to p-n junctions, Schottky barrier solar cells are cheaper to grow and fabricate; they are also expected to improve the spectral response because of near surface depletion regions in the shorter wavelength regions. In this particular work on InGaN based solar cells, a Schottky diode structure was used to avoid the issue of highly resistive p-type InGaN. In this study, platinum (Pt) is used to form a Schottky barrier with an InGaN/GaN absorber region. Electrical and optical properties of platinum films are investigated as a function of their thickness. InGaN/GaN Schottky solar cells with platinum as the transparent conductive film are reported and their performance is evaluated as a function of the metal thickness.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Electrical Engineering

Department dc:contributor.department

Electrical and Computer Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2014

Author dc:creator

• Jain, Aditya

Chair dc:contributor.committeechair

• Guido, Louis J.

Committee members dc:contributor.committeemember

• Plassmann, Paul E.
• Lu, Guo Quan

• Transparent conductive layer
• Schottky solar cell
• Device characterization

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

vt_gsexam:3693

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/50527