Abstract: ABSTRACT: BACKGROUND: Microarrays are an invaluable tool in many modern genomic studies. It is generally perceived that decreasing the size of microarray features leads to arrays with higher resolution (due to greater feature density), but this increase in resolution can compromise sensitivity. RESULTS: We demonstrate that barcode microarrays with smaller features are equally capable of detecting variation in DNA barcode intensity when compared to larger feature sizes. The barcodes used in this study are the well-characterized set derived from the Yeast KnockOut (YKO) collection used for screens of pooled yeast (Saccharomyces cerevisiae) deletion mutants. We treated these pools with the glycosylation inhibitor tunicamycin as a test compound. Three generations of barcode microarrays at 30, 8 and 5 micron features sizes independently identified the target of tunicamycin to be ALG7. CONCLUSIONS: We show that the data obtained with 30microm feature size is of comparable quality as the 5microm size and propose that further shrinking of features could yield barcode microarrays with equal or greater resolving power and, more importantly, higher density.