# Presentation: 680070

## Silicon Microstrip Tracker: production and performance

**Status Report**
**Flera Rizatdinova (KSU)**
**for D0 SMT group**
**D0 Workshop**
**June 20, 2000**

## Physics Requirementsto SMT

- Top physics, EW physics, Higgs physics, searches for physics beyond SM: good performance for tracks with high pT in |good performance for jets;
- B-physics: good performance for tracks with low pT in |
- As small as possible number of dead and noisy channels; small impact of alignment to the detector resolutions; small inefficiency and fake hit rate; resistance to irradiation.

## Silicon Microstrip Tracker

- 6 Barrels
- 12 F-Disks
- 4 H-Disks

## Barrel ladders

******72 ****SS****  - 144 ****DS_90****o****  -  216 ****DS_2****o**

|  | B1&B6 (large z) | B2-B5 (small z) |
| --- | --- | --- |
| Layer 1 |  12 SS | 12 DS_90o  |
| Layer 2 |  12 DS_2o | 12 DS_2o |
| Layer 3 |  24 SS | 24 DS_90o  |
| Layer 4 |  24 DS_2o | 24 DS_2o |

## 3-chip single sided detectors:production status

- Necessary for barrels              :  72
- Produced (06/11/00)               :  60
- (A+B)******  Graded                      :  47
- Tests/Repair                            :  11
**Need (assuming 90% yield) :13-18**

- Have enough sensors and High Density Interconnetors (HDI’s) to produce the rest of the detectors.

***** A grade : fraction F of the dead + noisy channels F<2.5%; B grade: F<5%***

## 3 chip SS detectors: performance of  (A+B) graded ladders

- Good electrical characteristics;
- Small fraction of the dead (1.5%) and noisy (0.4%) channels;
- In 82% cases, the dead channel are distributed uniformly.

## 6-chip double sided detectors:production status

- Necessary for barrels (layer 1 + layer 3)  :  144
- Produced for layer 1                                 :  34
- A+B Graded  for layer 1                           : 32
**Need for layer 1 (assuming 94% yield) :  20**
- Produced for layer 3                                  : 73
- A+B Graded  for layer 3                           :  61
**Need for layer 3 (assuming 83% yield) :  54**

- Have enough HDI’s  for the rest production. Production paced by sensor delivery (need 74 sensors more from Micron)  maximum production rate is 5/week. The total production can be completed at the end of September.
- Will use some detectors with p-stop shorts (a little bit more noisy channels compared to detectors without this defect).

## 6-chip DS detectors: performance of (A+B) graded ladders

- Good electrical parameters;
- Average random noise on p and n-sides is small;
- Inefficiency: 0% for strips with charge larger that 1⁄2 MIP; fake hits: 7% for NOISY channels; 0% for good strips. But coherent noise can have significant effect on rate of fake hits.

## Barrel: performance of layers 1 and 3

- Fraction of the dead channels is 1.2% and fraction of noisy channels is 0.4% - GOOD!;
- Small number of the groups of dead channels. In ~85% cases – uniform distribution of dead channels.

## 9-chip double sided stereo detectors:production status

- Necessary for barrels              : 216
- Produced (06/19/00)               : 163
- (A+B) Graded                         : 114
- Tests/Repair                            : 27
**Need (assuming 90% yield) : 90**

- Production is delayed by HDI delivery  maximum production rate is 10 detectors per week. In 7 weeks the total production can be completed.

## 9-chip DS stereo detectors: performance of (A+B) graded  ladders

- Good electrical parameters;
- Average random noise on p and n-sides is small;
- Inefficiency due to the readout threshold is the same as for 6-chip DS 900 detectors: 10% for strips with 1/3 MIP charge and 0% for strips with charge larger than 1⁄2 MIP. Coherent noise can impact the fake hit rate.

## Barrel: performance of layers 2 and 4

- Fraction of the dead channels is 2% on both sides.Fraction of noisy channels is 0.6% on p-side and 0.3% on n-side;
- Small number of the groups of dead channels. In ~90% cases – uniform distribution of dead channels.

## Barrel:  alignment

* *Measured:  Berillium  edges with respect to silicon. Precision of the individual measurement is better than 4 m in the ladder plane and better than 20 m in the perpendicular plane.

**beam**

- Rotation along the ladder

-  of 50 m induces the error of 2 microns in inner layers.

## Barrel: alignment

-  of 10 microns induces error of  2.9 microns

- Rotation in the ladder plane

**beam**

- Slope of the ladder with respect to beam

-  of 50 microns induces error of  3.3 microns in inner layers

## Schedule of barrel assembly

| Milestone | Schedule | Assembled |
| --- | --- | --- |
|  |  |  |
| Barrel 1      Done |  April 18, 2000 |  May 18, 2000 |
| Barrel 2      Done |  May 23, 2000 | June 13, 2000 |
| Barrel 3   Started |  June 28, 2000 |   |
| Barrel 4 |  July  27, 2000 |  |
| Barrel 5  | August 24, 2000 |  |
| Barrel 6 | September 22,  2000      |  |

- Some problems with grounding – work is in progress.

## F-wedges: production status

- Necessary for disks                 : 144
- Produced (06/11/00)               : 110
- (A+B) Graded                         : 58
- Tests/Repair                            :  26
**Need (assuming 90% yield) :  60**

- Enough sensors on hand to build full complement of F-disks.

**Electrical characteristics of (A+B) graded F-wedges**

- Two groups of the detectors: with low operating voltage and high operating voltage.

## F-disks:  performance of (A+B) graded detectors

- Fraction of the dead channels on n-side is ~ 2 times larger than on p-side, but still small  (1.4%). Small fraction of the noisy channels on both sides.
- In ~90% cases dead channels are distributed uniformly along detectors.

## F-disks: alignment

**F-disks: alignment**

***y***

***0***

***x***

***a***

***b***

***1***

***2***

***3***

- Measure : x and y positions of two symmetric F-wedges using the points ***a*** and ***b ********* **define the ***R-***positions of the detector and rotation angle ;
- z position of every F-wedge independently using the points ***1***, ***2*** and ***3***

****

## F-disks: alignment

- No significant problems encountered with F-disk assembly so far.

## Schedule of F-disks assembly

| Milestone | Schedule | Assembled |
| --- | --- | --- |
|  |  |  |
| F-disk 0      Done | March 28, 2000 | March 31, 2000 |
| F-disk 1      Done  | April 11, 2000 |  May 10, 2000 |
| F-disk 2      Done |  April 25, 2000 |  May 23, 2000 |
| F-disk 3      Done | May 9, 2000 |  June 15, 2000 |
| F-disk 4  Started! | May 23, 2000 |  |
| F-disk 5 | June 21, 2000 |  |
| F-disk 6 | July 6, 2000 |  |
| F-disk 7 | July 20, 2000 |  |
| F-disk 8 | August 3, 2000 |  |
| F-disk 9 | August 17, 2000 |  |
| F-disk 10 | August 31, 2000 |  |
| F-disk 11 | Sept. 15, 2000 |  |
| F-disk 12 | October 6, 2000 |  |

## H-wedges:production status

- Necessary for disks                 :  96*2
- Produced (06/11/00)               :  177
- A+B Graded                           :  135
- Tests/Repair                           :   14
**Need (assuming 88% yield) :  65**

- Have enough sensors to produce the rest of the detectors. Need more HDI’s and Be. Production was delayed by problems with encapsulation of the detectors – SOLVED!  Expect to start assembling the first H-disk at the end of June.

## H-wedges: performance of detectors to be installed in H-disks

- Good electrical characteristics;
- Small fraction of the dead (1.3%) and noisy (0.27%) channels.
- Small fraction of the groups of the dead channels.

## Conclusions

- Small percentage of dead and noisy channels in the (A+B) graded detectors.
- Low random noise in the (A+B) graded detectors.
- Good alignment of the detectors in assembled barrels and F-disks.
- The production of the detectors for barrels will be finished in  ~10-12 weeks.
- Barrel assembly, F-disk assembly and H-disk assembly are less that 1 month behind the schedule.
- Many thanks to everybody for your continuing efforts (shifts on tests) !