Recent progress on MIMOSA sensors

1. Recent progress on MIMOSA sensors A.Besson, on behalf of IReS/LEPSI : M. Deveaux, A. Gay, G. Gaycken, Y. Gornushkin, D. Grandjean, F. Guilloux, S. Heini, A. Himmi, Ch. Hu, K.Jaaskelainen, M. Pellicioli, H. Souffi-Kebbati, I. Valin, M. Winter, G. Claus, C. Colledani, G. Deptuch, W. Dulinski, M. Szelezliak (M6/M8 DAPNIA: Y. Degerli, E. Delagnes, N. Fourches, P. Lutz, F.Orsini) • Fabrication technology • Parameter optimization (pitch, T, diodes, etc.) • Signal treatment and read-out speed • Thinning • Radiation tolerance

2. MIMOSA 9 (1) • Main features: • Techno opto. • Self Bias / Standard • Pitch 20/30/40 m • Small/large diodes (3/6 m) • With/without epi. 0.96 mm 1.2 mm 3T, 40 m 32 x 32 SB, 30 m 32 x 32 5 x 5 m Explore the different parameters SB, 20 m 64 x 64 SB, 40 m 32 x 32 A.Besson

3. MIMOSA 9 (2) • Beam test @ CERN-SPS (120 GeV/c -) Charge (1 pixel); MPV ~ 325 (25 pixels); MPV ~870 (9 pixels); MPV ~ 850 MPV ~ 24 Self-Bias, Pitch = 20 m, diode 6 x 6 m2 A.Besson

4. MIMOSA 9 (3) • First comparisons: • SB with 20/30 m pitch : eff ≥ 99.8% • Resolution ~ 1.5 m @ 20 m pitch • Analysis in progress: • Temperature • Chip without epi. • Hit selection optimization Sp. Resolution; SB, diode 3.4 x 4.3 m2 Noise (e-) vs Diode surface m2 A.Besson

5. Fast read-out architecture • Different developments based on Mimosa 6 • VX DET layer 1-2: • Fast, column // readout, with hit selection • VX DET layer 3-4-5: • Multiple scans of the whole detector within train (r.o. ~200 s). • Then read the samples between trains • Integrate capacitors in each pixel (M7 and M8) • Mimosa 7 • Features • photoFET. • 25 m pitch, No epi., 0.35 m, 64x16 readout in // with CDS • Status • Being tested • Beam test in Oct. • Mimosa 8 (with DAPNIA) • Features • 25 m pitch, 8 m epi., 0.25 m, 128x32 readout in // with CDS • Signal discrimination • Status • Being tested A.Besson

6. Thinning • Mimosa 5 thinned down to epi. layer • Beam test. @ CERN • S/N M5-B thinned down M5-B standard A.Besson

7. MIMOSTAR • STAR exp. upgrade: 1st proto sent for fabrication • Extension of the Vertex Detector (2 layers) • Running conditions • T amb. (higher leakage current). Readout time ~ 4ms • Features • Opto technology to reduce noise • TSMC 0.25 techno • Based on M5 • Pitch = 30x30 m2. 128x128 pixels • Surface: ~ 4 x 5 mm2 • Subdivision in 10 groups of columns • Pure analogic output. 10x10MHz output • Status • Expected back from fab. end Oct. A.Besson

8. Radiation hardness • SUC 1: • Chip with 8  pixels design. 30 m pitch • Goal: study charge loss after irraditaion (X-ray) • Irradiation: • X-ray: 500kRad and 1MRad • Calibration with 55Fe • Measure leakage current @ different T • Being analysed • Charge loss  for some pixel designs • Leakage current • Next irradiation + beam test • M9 (X, n) • M5 (n)  Seems to stand 1 MRad A.Besson

9. Conclusion and outlook • Geometry • Efficiency and resolution ok from 20 to 40 m • New techno opto. AMS 0.35 m • Epi. Layer may change • Chip read-out architecture • 2 research lines • layer 1-2 : r.o. speed • Layer 3-4-5 : storage capacitors • 2 proto being tested • Promising results • Radiation hardness • Studies in progress • Evidence  stand > 0.5 MRad. Up to 1MRad. • M9 (n,X), M5 (n) A.Besson

10. Mimosa prototypes A.Besson

11. A.Besson

12. A.Besson

13. A.Besson

14. A.Besson

15. Mimosa 9 (preliminary) A.Besson

16. Beam tests: résumé. • 3 sessions (mai, juillet, aout). • Chips testés: • M5B: 202, 205, 306. • M5 15 m: “nGD” • M9: 1,2 (avec epi.) et 7(sans epi.) • 150k evts/run. 3/4 pts de Temp. • Remarques • Inversion du trigger pour M5 15 m • Veto apres le reset pour M9. 2  10 frames. • ~ 50% d’efficacité… • A faire: • Calibration M5 nGD. • M9 sans epi. • M5 et M9 irradiés • M7 A.Besson

17. A.Besson