Threading dislocation density characterization in III–V photovoltaic materials by electron channeling contrast imaging

• Accurate TDD quantification is important for metamorphic III–V solar cells.
• ECCI measures TDD values over a wide range from ~5×106–5×108 cm−2.
• ECCI is useful for dislocations in clusters closer than 0.2 µm.
• Comparison of TDD in ECCI with both EBIC and DSE show close agreement.

Accurate and rapid threading dislocation density (TDD) characterization of III–V photovoltaic materials using electron channeling contrast imaging (ECCI) is demonstrated. TDDs measured using ECCI showed close agreement with those from electron beam-induced current mapping (EBIC) and defect selective etching (DSE). ECCI is shown to be well-suited for measuring TDD values over a range of ~5×106–5×108 cm−2. ECCI can distinguish individual dislocations in clusters closer than 0.2 µm, highlighting its excellent spatial resolution compared to DSE and EBIC. Taken together, ECCI is shown to be a versatile and complementary method to rapidly quantify TDD in III–V solar cells.