Development of a micro array type electron multiplier

We are currently developing a micro array type electron multiplier which can be used for a two dimensional photomultiplier tube (PMT). This device consists of dynode plates which have many pixels. Keeping its position information, incident electrons are multiplied within each pixel of the array. The micromachining technique was used to fabricate the dynodes of the detector. Slanting hole and pyramid hole structures were investigated as the dynode structure. From the simulation result of these two types, more than 1000 would be obtained as the signal gain factor with 12 dynodes and 200V/dynode. From the experimental results, the electron multiplication factor /spl sim/2 of the pyramid type dynode was obtained with 2 dynode stages and 1SOV/dynode. The signal gain factor 4.6 of the slanting hole dynode was obtained with 2 dynode stages and 400V/dynode. These well agree with the simulation results.