A delivery device for thin-film material deposition onto a substrate comprising: (a) a plurality of inlet ports comprising at least a first inlet port, a second inlet port, and a third inlet port capable of receiving a common supply for a first gaseous material, a second gaseous material, and a third gaseous material, respectively; (b) at least one exhaust port capable of receiving exhaust gas from thin-film material deposition and at least two elongated exhaust channels, each of the elongated exhaust channels capable of gaseous fluid communication with the at least one exhaust port; (c) at least three groups of elongated emissive channels, (i) a first group comprising one or more first elongated emissive channels, (ii) a second group comprising one or more second elongated emissive channels, and (iii) a third group comprising at least two third elongated emissive channels, each of the first, second, and third elongated emissive channels capable of gaseous fluid communication, respectively, with one of the corresponding first inlet port, second inlet port, and third inlet port; wherein each of the first, second, and third elongated emissive channels and each of the elongated exhaust channels extend in a length direction substantially in parallel; wherein each first elongated emissive channel is separated on at least one elongated side thereof from a nearest second elongated emissive channel by a relatively nearer elongated exhaust channel and a relatively less near third elongated emissive channel; wherein each first elongated emissive channel and each second elongated emissive channel is situated between relatively nearer elongated exhaust channels and between relatively less nearer elongated emissive channels; (d) a gas diffuser (140; 150; 152, 154; 160; 162; 164) associated with at least one group of the three groups of elongated emissive channels such that at least one of the first, second, and third gaseous material, respectively, is capable of passing through the gas diffuser (140; 150; 152, 154; 160; 162; 164) prior to delivery from the delivery device to the substrate, during thin-film material deposition onto the substrate, and wherein the gas diffuser (140; 150; 152, 154; 160; 162; 164) maintains flow isolation of the at least one of first, second, and third gaseous material downstream from each of the elongated emissive channels in the at least one group of elongated emissive channels; wherein the gas diffuser (140; 150; 152, 154; 160; 162; 164) is capable of providing a friction factor that is greater than 1x10 2, assuming a representative gas that is nitrogen at 25°C and a representative average velocity between 0.01 and 0.5 m/sec of gaseous material passing through the gas diffuser; characterized by associating the gas diffuser (140; 150; 152, 154; 160; 162; 164) with each of the three groups of elongated emissive channels such that each of the first, second, and third gaseous material, respectively, is capable of separately passing from the delivery device to the substrate during thin-film material deposition on the substrate, and wherein the gas diffuser (140; 150; 152, 154; 160; 162; 164) maintains flow isolation of each of first, second, and third gaseous material downstream from each of the elongated emissive channels in the three groups of elongated emissive channels, wherein the gas diffuser (140; 150; 152, 154; 160; 162; 164) is a mechanical assembly housing separate flow paths associated with each of the first elongated emissive channels, separate flow paths associated with each of the second elongated emissive channels, and separate flow paths associated with each of the third elongated emissive channels. (a) a plurality of inlet ports comprising at least a first inlet port, a second inlet port, and a third inlet port capable of receiving a common supply for a first gaseous material, a second gaseous material, and a third gaseous material, respectively; (b) at least one exhaust port capable of receiving exhaust gas from thin-film material deposition and at least two elongated exhaust channels, each of the elongated exhaust channels capable of gaseous fluid communication with the at least one exhaust port; (c) at least three groups of elongated emissive channels, (i) a first group comprising one or more first elongated emissive channels, (ii) a second group comprising one or more second elongated emissive channels, and (iii) a third group comprising at least two third elongated emissive channels, each of the first, second, and third elongated emissive channels capable of gaseous fluid communication, respectively, with one of the corresponding first inlet port, second inlet port, and third inlet port; (d) a gas diffuser (140; 150; 152, 154; 160; 162; 164) associated with at least one group of the three groups of elongated emissive channels such that at least one of the first, second, and third gaseous material, respectively, is capable of passing through the gas diffuser (140; 150; 152, 154; 160; 162; 164) prior to delivery from the delivery device to the substrate, during thin-film material deposition onto the substrate, and wherein the gas diffuser (140; 150; 152, 154; 160; 162; 164) maintains flow isolation of the at least one of first, second, and third gaseous material downstream from each of the elongated emissive channels in the at least one group of elongated emissive channels;