Table 1.

Characteristics of diverse 3D printing methods for freeform electronics

Printing methods		Advantages	Disadvantages	Materials	Printing resolution	Applications
Inkjet printing	E‐jet	‐High resolution ‐Variety of materials	‐Nozzle clogging problem ‐Highly dependent on substrate conductivity ‐Low yielding rate	‐Conducting material[ 100 , 150 , 204 , 205 ] ‐Semiconducting material[ 63 , 206 , 207 , 208 ] ‐Insulating material[ 209 , 210 , 211 ]	>50 nm[ 212 ]	‐Supercapacitor[ 100 ] ‐Thin‐film transistor[ 63 ] ‐Interconnect[ 150 ]
	Aerosol jet	‐High resolution ‐Variety of materials ‐Complex patterns printable on nonplanar surfaces	‐Substantial amount of overspray ‐Supplying system required ‐Coffee‐ring effect	‐Conducting material[ 95 , 107 , 149 , 213 , 214 ] ‐Semiconducting material[ 106 , 107 , 215 , 216 ] ‐Insulating material[ 217 , 218 ]	>85 nm[ 95 ]	‐Photodetector[ 106 ] ‐Thin‐film transistor[ 107 ] ‐Interconnect[ 149 ]
Direct writing		‐High resolution ‐Complex patterns printable ‐Fast printing speed ‐One step process	‐Highly dependent on the rheology between ink and substrate ‐Low scalability ‐Nozzle processing required	‐Viscous ink[ 54 , 108 ] ‐Liquid metal[ 9 , 56 ]	>630 nm[ 195 ]	‐Interconnect[ 9 , 56 ] ‐Battery[ 159 ] ‐Antenna[ 170 , 171 , 178 ]
Photocuring	SLA	‐Easy set‐up conditions ‐Large scale printable	‐Volume shrinkage after printing ‐Slow printing speed	‐Photocurable resin ‐Ceramic resin	>0.6 µm[ 219 ]	‐Tissue scaffold[ 127 ]
	DLP	‐High precision ‐Fast printing speed	‐Volume shrinkage after printing ‐Small scale printable only ‐High cost	‐Photocurable resin ‐Ceramic slurry	>50 µm[ 220 ]	‐Dental field[ 221 ] ‐Jewelry casting[ 222 ]
	CLIP	‐Fast printing speed ‐High mechanical strength	‐Coarse resolution ‐High cost	‐Low viscosity photocurable resin	>100 µm[ 133 ]	‐Point‐of‐care service[ 133 ] ‐High strength‐to‐weight‐ratio[ 133 ]
	TPP	‐High resolution ‐In‐vivo usable	‐Transparent materials printable only ‐Slow printing speed	‐Transparent photocurable resin	∼100 nm[ 223 ]	‐In‐vivo biomedical applications[ 138 , 224 ]