Preparation of Module Assembly and Stringtest Haridas Heinz

Preparation of Module Assembly and Stringtest Haridas, Heinz, Marge • • One possibility for an assembly and test line? Preparation of a full string test – aim of the tests – what are the parameters of DS, MS and Module Setup for String test and Laser test Next future Phobos Coll. Meeting @MIT April 97

One possibility for an assembly line Test of - PA chip - PL chip - DS Module rework DS assembly (fast) Module function test DS pool MS assembly soon now Module bonding MS bonding Module glueing Test of MS MS rework Sensor pool Module calibration Module “long time” stability test Module alignment measurement

What do the tests aim for? • Learn parameters of DS, MS and module – production (get selection critierias for DS+MS+sensors) – later operation (influence of Supply voltages, threshold, . . . ) • Module function and reliability – minimize effect of single component failure (eg. high leakage current on one sensor, defect DS on module) – test reliability of connections • Stability – of noise, detector current, signal • Signal response – signal calibration (gain, linearity) – dead channels

What are the parameters? tested on every component • DS – dead channels – threshold – noise and signal gain • MS – digital part and readout – voltages on DS • Module – dead pads, noise, Idet, signal gain (-> Database) – optimal threshold on few components • DS – influence of supply voltages on signal gain, noise, linearity. . . • MS – clock transmission – crosstalk, output signals • Module – signal response and noise of different module types (correlation d. E/dx vs Signal)

Test Setups in preparation - The Stringtest verify that the module works PA 16 • “Stringtest” Setup – now: for tests of DS – soon: test of MS – final: fast test of modules after glueing, rework • Use of test pulses for – test function – noise measurement – gain & linearity • Add a sensor to one DS PL 8 Amod Csource ENC vs load capacitance Q=Ct*V Ct V test gain & linearity in 0 -5 MIP range (e. g. Ct=1. 0 p. F V=3. 8 m. V ->Q= 1 MIP

Test Setups in preparation - The Lasertest understand the signal response • Calibrate the signal response – measure each pad for 1, 2, 5, 10 MIP – find dead channels – create Database • Stability test by source – noise – MIP signal (12 h@2 Hz = 28 hits/pad for 2 T 1 = 84 hits/pad for 4 T 5 – detector current 1064 nm laser Sr 90 source Idet Problems: absolute laser calibration, time stability, very precise X-Y stage support - optics, cooling, test time, . . .