Brazilian Tunable Filter Imager (BTFI) Preliminary Design Review (PDR)‏ USP-IAG Universidade de São Paulo 18-19th June 2008 Julian David Rodriguez Javier Ramirez Fernandez SIM-PSI-EPUSP

2BTFI PDR – 18,19 June 2008 Test system of Electron Multiplying Charge Coupled Device for Brazilian Tunable Filter Imager Objective The objective of this work is to evaluate the performance of the detector system in the microelectronic laboratory (LME), before the detector system is used in BTFI instrument.

3BTFI PDR – 18,19 June 2008 EMCCD This new EMCCD detector requires a new controller to obtain vantage in the capacity of counting photons and for reducing readout noise’s through the electron multiplication of the signal BTFI will use Montreal’s CCCP controller

4BTFI PDR – 18,19 June 2008 Detector Tests: First Stage Evaluate and test BTFI’s lab EMCCD system Gain experience running CCCP, BTFI’s detector controller Build a controlled illumination source for detector testing Establish the set of tests to produce detector characterization data. Script them to run automatically

5BTFI PDR – 18,19 June 2008 Detector Tests: Second Stage To execute a complete characterization of EMCCD in the laboratory and compare the results with others research groups. Submit papers to Detector Conferences with the characterization results obtained with BFTI’s EMCCDs Preparation of the EMCCD documentation for incorporating in the final project BTFI system

6BTFI PDR – 18,19 June 2008 Detector Characterization We will characterize the following properties of the EMCCD : Gain Multiplication Gain and its dependence on temperature Dark current and its dependence on temperature Noise sources Clock Induced Charge (CIC) ‏ Multiplication noise Readout noise Linearity Silicon band-gap energy Charge Transfer Efficiency (CTE) ‏

7BTFI PDR – 18,19 June 2008 Clock Induced Charge - CIC CIC is caused by impact ionisation of the holes as they move in and out of the Si/SiO2 interface during clocking CIC is caused by impact ionisation of the holes as they move in and out of the Si/SiO2 interface during clocking The charge generated is dependent on the number of transfers through the CCD not the integration time The charge generated is dependent on the number of transfers through the CCD not the integration time Dependent on clock amplitude, transfer rate and clock timing Dependent on clock amplitude, transfer rate and clock timing If sufficient cooling is not available (BTFI lab system uses Thermo-electric cooling), multi phase pinned (MPP) operation can be used. This makes the system susceptible to CIC, but this can be minimized by careful choice of operating conditions If sufficient cooling is not available (BTFI lab system uses Thermo-electric cooling), multi phase pinned (MPP) operation can be used. This makes the system susceptible to CIC, but this can be minimized by careful choice of operating conditions In MPP operation, the clock inverts the silicon surface, saturating it with holes In MPP operation, the clock inverts the silicon surface, saturating it with holes 7

8BTFI PDR – 18,19 June 2008 Xxxx 8

9 EM Gain 9

10BTFI PDR – 18,19 June 2008 EMCCD Noise 10

11BTFI PDR – 18,19 June 2008 CCD97 – BTFI’s Lab EMCCD 11

12BTFI PDR – 18,19 June 2008 CCD97 Diagram 12

13BTFI PDR – 18,19 June 2008 CCD97 Video Output 13

14BTFI PDR – 18,19 June 2008 CCD97 QE Plot 14

15BTFI PDR – 18,19 June 2008 CCD97 – Results to be Found Variation of Multiplication Gain with High Voltage clock and Temperature Variation of Dark Current with Temperature

16BTFI PDR – 18,19 June 2008 Current Status Ongoing EMCCD study Characterization plans implemented in the next 2 months Controlled illumination source being designed and built at LME BTFI lab detector system to be first integrated in Sept’08, using AstroInventions’ Test Dewar Continuous tests until BTFI’s science cameras arrive (Q2 09) ‏