Abstract: A method, apparatus, and computer program products for fabricating multiple chemical arrays on a substrate, each array having multiple rows of feature locations with arrays of different sets being arranged in a sideways orientation with respect to the rows. The method includes dispensing drops from a drop dispensing head onto the substrate while maintaining a gap between the head and substrate and moving them relative to one another along a path so as to fabricate the arrays. The path for the relative moving includes moving the head in a direction along the rows of a first array set then moving the head in an opposite direction along the rows of a second array set. This pattern is repeated with the second array set of an earlier cycle being the first array set of a later cycle.

Abstract: A method, apparatus, and computer program products for fabricating multiple chemical arrays on a substrate, each array having multiple rows of feature locations with arrays of different sets being arranged in a sideways orientation with respect to the rows. The method includes dispensing drops from a drop dispensing head onto the substrate while maintaining a gap between the head and substrate and moving them relative to one another along a path so as to fabricate the arrays. The path for the relative moving includes moving the head in a direction along the rows of a first array set then moving the head in an opposite direction along the rows of a second array set. This pattern is repeated with the second array set of an earlier cycle being the first array set of a later cycle.

Abstract: A method, apparatus, and computer program products useful in fabricating a chemical array. The apparatus may include a head system, transport system, and a processor. The head system has multiple groups of drop dispensers. The transport system moves the head system with respect to a substrate. The processor dispenses drops from dispensers during operation of the transport system, in a pattern along a selected path for each group. The method, apparatus, and computer program products provide a means by which error dispensers can readily be replaced by redundant non-error dispensers loaded with the same fluid.