Researchers at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, have demonstrated a novel and groundbreaking way to additively print gallium nitride (GaN) – a material that can be used to produce semiconductor power devices as well as radio-frequency components and light-emitting diodes – using a combination of liquid and gas.

Their work was detailed in “A pathway to compound semiconductor additive manufacturing,” published recently in the journal MRS Communications.

“Gallium nitride is a material of significant interest for optoelectronic applications, solar power generation and high-power distribution,” said Jarod Gagnon, a materials scientist in APL’s Research and Exploratory Development Department and lead author on the paper. “Being able to 3-D-print semiconductors gives us the ability to make complex devices that are either too costly or too complex to make with current techniques. If we’re successful with our research, this will open a new path forward for a rapid change in how we operate in the semiconductor and electronic device field.”

GaN printing represents a new category of 3D printing that Gagnon and his colleagues refer to as “gas-phase reactive AM.” Building off of work completed under a 2018 Combustion Grant, the team combined additive manufacturing techniques — in this case, material extrusion — with semiconductor synthesis techniques (liquid phase epitaxy and metalorganic chemical vapor deposition) to react with the material as it’s printed. “This is what allowed us to form single-crystal oriented material through epitaxial growth,” Gagnon said.

The team is the first to report on this concept; Gagnon attributes the scarcity of research to a disconnect between the two fields of additive manufacturing and semiconductor synthesis.