A novel optical detector cell for use in miniaturized total chemical analysis systems

The use of silicon´s optical and mechanical properties is demonstrated in a silicon-based, small-volume, optical flow cell. Cells having volumes ranging from 1 to 100 nL and lengths of 1 and 5 mm have been constructed using a basic micromachining process. Cell depths of 50 to 100 mu m and widths of 50 and 300 mu ms across demonstrate the applicability of silicon micromachining to fabrication of cells having dimensions not attainable by conventional machining methods. Utilization of silicon crystalline planes to couple light into and out of the cell through a series of reflections should improve detection limits obtainable using these cells, as effective optical pathlength can be increased beyond actual cell length.<>