MPC-Ex Project in Korea Y. Kwon Yonsei University on behalf of Korean MPC-EX group

J.S. Chai5, K.I. Hahn2, S.Y. Han2, H.S. Hong4, K.S. Joo4, D.S. Kim4, E.J. Kim1, Y.K. Kim3, Y. Kwon6, J.H. Lee 1, K.S. Lim4, H.J. Moon4, H.M. Park4, J.M. Park 1, S.Y. Park, D.G. Sue6 Chonbuk National University. 1 ETRI. 2Ewha Womans University. 3Hanyang University, RISP. 4Myongji University. 5Sungkyunkwan University. 6Yonsei University.

PHENIX MPC-Ex detector (Muon Piston Calorimeter, An EMCal) MPC-Ex (MPC Extension) 0 &  3 < |y| < 4 separation up to E>100 GeV

Si-W sandwich preshower detector ~1X0 MPC-Ex MPC -RM<y<RM (EM Shower by single e) y z

General(Operation) -

Fabrication process Metal layer deposition Passivation Etch for contact Ion implant High purity Si wafer Oxidation Oxide layer deposition

Possibility in Korea R&D environment 6 inch fabrication line 1 cm2 ~ $ 2 6 inch fabrication line 8 inch fabrication line

Actual process sheet

Fabricated minipad sensor

Dicing sensor This shows the sensor dicing. After sawing the wafer, it attached to the kind of sticker. So we need to pickoff process. And after the pick off process, we get the minipad sensor.

Issues

Novel guard ring system design and implementation 2013 IEEE NSS/MIC/RTSD, COEX, Seoul, Korea, October 27-November 2, 2013 Novel guard ring system design and implementation for punch-through protection toward the detector dicing edge with improved radiation tolerance and reduced dead area *This research was supported by the U.S. Department of Energy: Contract No. DE-AC02 -98CH10886 Zheng Li, Wei Chen, Edward Kistenev, and Andrei Sukhanov Brookhaven National Laboratory, Bldg. 535B, Upton, NY 11973-5000, USA Youngil Kwon, Dong gon Sue Department of Physics, Yonsei Univ., 50 Yonsei-ro, Seoul, 120-749, Korea Kunsik Park, Jongmoon Park Electronics and Telecommunications Research Institute, 218 Gajeong-ro, Daejeon, 305-700, Korea John Lajoie Iowa State University, 2229 Lincoln Way Ames, IA 50011, USA

Old GRS --- Struture It is a typical multi-guard ring system to ensure high voltage operations, see refs [1-6]

Old GRS --- Simulations V=250 V and oxide charge density of 1x107/cm2 High leakage current may be due to the punch-through effect to the dicing edge p+ implants area that is highly damaged with a finite electric field for current injection

2 Concept of Novel GRS Lower E-fields Segmented, low-dose n+-implant A segmented, low-dose (a few times of 1012/cm2) n+-implant on near GRS can remove the detector oxide-property dependence with lower E-field

3 Simulations Depletion edge far away from dicing edge Electron concentration profile One can dice it here – Reduction in dead space of 500 m! Since the implanted charge is much higher than that induced by oxide irradiated to 10 Mrad, it is rad-tolerant to 10 Mrad V=200 V and oxide charge density of 2x1011 to 2x1012 /cm2

Improvements (Details by K.S. Lim) 30  1.5 cm 3 cm 1 2 3 4 6 cm

Submission for main production Main production started and new submission will be made in every 3 weeks. 1st submission(executed), the last week of Sep. 2nd submission(executed), the 3rd week of Oct. 3rd submission(planned), the 2nd week of Nov.

Sensor Certification log (Details by S. Y. Hahn) CV test Before dicing Short test Guard ring & pattern leakage current test After dicing Stability : x3 of full depletion voltage (90V) & 2 hours So from these result we could make the outline of sensor certification logging system. The first feature that we need to make data is capacitance verses voltage. And Before the dicing process, we need to do the short test and leakage current test of guard ring and pattern for certificate each steps of fabrication are done properly. And after the dicing process, we need to do the guard ring and pattern leakage current test for check the overall sensor performances and also stability test applied 3 times of full depletion voltage and in two hours.

Summary Korea has a good potential in silicon sensor. A sequence of R&D for the silicon minipad sensor has been performed. Main production has started. Sensor log has been defined.