Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 1 DØ Inner Layer Sensor Production Readiness Review August 08, 2003 M. Demarteau, G. Ginther ‘Response to Committee Comments on Outer Layer Sensor Review ’

Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 2 Sensor Specifications  sensor specifications were well designed and sufficient; however, several issues arose which need to be clarified in discussions with Hamamatsu Photonics (HPK); Recommendation: Make revisions to the specifications as appropriate based on the following points:  The specification for the detector full depletion voltage is V dep 40 V seems appropriate, but should be discussed with HPK to ensure no impact on cost.  The recommendation to specify a lower limit for the detector full depletion voltage of 40 V has been adopted and the specifications have been adjusted accordingly.  Comment from Hamamatsu: 1) specifications a) The change about 40V < Vdep < 300V is not a problem for us.

Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 3 Sensor Specifications  The specification of wafer warp less than ±25  m is too stringent, and in practice it may be too difficult to achieve. This specification was not met for the prototype sensors. DØ should understand what the real specification should be. The final sensor warp might be less once the sensor is glued down. This should be investigated and quantified.  The specification of wafer warp has always been on a ‘best effort’ basis with Hamamatsu. For the Layer 1 sensors Hamamatsu has shown that it can achieve wafer warps that are within our ±25  m window. Our prototype modules show that we can tolerate wafer warps of ±50  m. We communicated our warp requirements to HPK: “We have relaxed the sensor warp to 100  m, that is that the sensor has to fit within two parallel planes 100  m apart. We would like to view this as an upper limit; if a sensor has a larger warp we reserve the right to reject the sensor.” We continue to work with Hamamatsu on a best effort basis for wafer warp, to emphasize that wafer warp is a critical parameter for us.  Comment from Hamamatsu c ） The chip warp should be within 100  m max. on the prototypes. Do you have the measured data on it ? If so, provide the same with us, please.

Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 4 Sensor Specifications  Stave height along the length of the stave; Note, current tooling for stave assembly not very flat. 75  m

Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 5 Sensor Specifications  HPK will not do whole-wafer visual inspections for open-circuits or short- circuits, so this part of the specification should probably be deleted.  The experience with Hamamatsu is indeed that they are confident enough in the quality of their product that they deem whole-wafer visual inspections for open-circuits or short-circuits at the company redundant. Given that Hamamatsu has accepted this requirement we consider it prudent to leave it as part of our specifications. Recent quality assurance measurements of the CMS collaboration reinforce our notion that quality assurance at the vendor should be emphasized.

Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 6 Sensor Specifications  The mask alignment specification (±2.5  m) is not stringent enough. Mask alignment of ±0.5  m should be achieved in order to ensure proper metal- implant overlap.  Our response to committee: The recommendation to make the mask alignment specification of ±2.5  m more stringent was adopted. The prototype sensors show that Hamamatsu is able to achieve a mask alignment to better than ±0.5  m, and that is our new specification.  Response from Hamamatsu: mask alignment tolerance of +/-0.5um is very tough for us. Could you kindly accept the +/-2um tolerance although the most pcs should be covered by about +/-1um tolerance ?  We accepted their proposal. We now also receive test structures with alignment marks on them.

Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 7 Sensor Specifications  The average coupling capacitance was 105 pF, about 12 pF below the minimum specification. The measurement should be checked - the reason why the specification was not met should be identified and corrected, or the specification should be revised.  The coupling capacitance measurements shown at the review were taken at 10kHz. The full frequency dependence of the coupling capacitance was measured and a low frequency limit of 140 pF was obtained, which is well within our specifications. (more results today)

Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 8 Sensor Testing and QA  Our testing seemed to indicate more bad channels than identified by HPK. Recommendation: Discuss the discrepancies as soon as possible with HPK to understand the cause for each discrepancy. This will ensure the integrity of the HPK measurements, which are relied upon for identifying bad strips for the majority of sensors.  Those sensors that showed many more defects in our own QA tests than at Hamamatsu were re-measured at Fermilab. It was found that some of the flaws previously identified were a result of a bad contact between the probe and the sensor.  After the review, the QA program at the testing centers was reviewed and some significant shortcomings in the setup were identified and rectified. Results on site qualification and comparison will be shown today  Only two sensors showed defects that were not identified at Hamamatsu. Those results have been communicated to the vendor.  HPK response: #29) We are afraid they are scratches made after our pre-shipping test. #5) Regarding increase of pinhole at your test from ours, complete elimination is unlikely in consideration of an insulation layer's life. In fact, higher voltage than 80V (say 100 to 120V) is applied on our inspection, which should be useful for a screening purpose. Incrase of pinhole of a few channels may not be avoided.

Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 9 Irradiation  Recommendation: The KSU facility’s dosimetry needs to be fully understood and sensors should be irradiated at alternative facilities with well-understood dosimetry The post-irradiation measurements need to be re-examined and fully understood.  Tim Bolton’s talk will address the dosimetry. For the previous PRR the area of an L1 sensor was mistakenly used in the normalization of the flux (see Bolton’s talk). We have not performed a cross-check of the results at alternate facilities, but rather have performed a cross check of copper foil activation measurements at Fermilab  Updated results for outer layer sensors made available for this PRR  Results from irradiation of Layer 1 sensors to be presented today, with new dosimetry calibration.

Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 10 QA  Recommendation: Identify a physicist who is experienced with sensor device testing and properties to be responsible for the overall testing and QA program. This physicist should spend a significant fraction of his/her time on sensor QA, full-time if needed. Consistency of measurements between the different facilities should be ensured by selecting a subsample of detectors and comparing the results of the same QA tests performed at each facility.  Mme. Mao and Ralf Bernhard will be full time dedicated physicists to the overall sensor testing and QA. More details in QA talk. Consistency of measurements between various facilities has been addressed (see McCarthy’s talk).

Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 11 SVX4 Noise Performance  Recommendation: Perform refined SVX4 noise studies with prototype modules using 396 ns crossing time electronics to understand issues like setup noise and post-irradiation shot noise. We recommend DØ get together with CDF to understand the SVX4 noise behavior.  After the review the noise measurements were revisited and results communicated to CDF. We continue to perform noise measurements with modules and irradiated modules exploring the full parameter space.

Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 12 Database  Recommendation: DØ should investigate if the database selected will serve the upgrade project smoothly through the entire project cycle. We recommend that this be done together with CDF and that databases of ongoing projects (CMS, ATLAS, GLAST) be investigated if the present choice is found deficient.  Response: Old database relied on student in computing department at UIC. Concerns about long term stability, support and flexibility motivated us to adopt the ATLAS database design with full support from the Dzero online group. Please see today’s QA presentation

Dzero RunIIb Sensor PRR, August 8, Marcel Demarteau Slide 13 Hamamatsu Delivery Schedule  Recommendation: Obtain a firm commitment of the delivery schedule from HPK to clarify the delivery rate for each month of the project duration. Dzero ScheduleCDF Schedule