Initial Measurements of a Silicon on Carbon Fiber

Initial Measurements of a Silicon on Carbon Fiber Structure (Layer 1) Bill Cooper Fermilab (Layer 5) VXD Bill Cooper Vertex Detector Mechanics – 2 October 2007

Introduction • The University of Washington fabricated the cylindrical portion of the CF support structure and fabrication and assembly mandrels. • Fermilab provided CF end rings and attached them to the structure. • Mike Hrycyk set up assembly fixturing on a CMM and glued 75 µm silicon to the CF structure. • Si. Det has measured exposed silicon surfaces and edges using a “feather probe”. – Nominal probe force = 10 mg – 1 mm tip diameter Bill Cooper Vertex Detector Mechanics – 2 October 2007 2

First Results • Only surface measurements of the first set of data have been analyzed. • On the exposed surface of each “sensor”, measurements were made at 3 transverse locations and 5 longitudinal locations (3 x 5 grid). – Total of 90 surface measurements per data set – Data analysis assumed: • All surfaces should have ideal spacings in azimuth and share a common centerline. • A single A-layer radius • A single B-layer radius Bill Cooper Radii above correspond to 100 µm silicon. Actual silicon thickness = 75 µm. Vertex Detector Mechanics – 2 October 2007 3

First Results • Fit radii: – R_A = 14. 148 mm – R_B = 15. 283 mm – Radii were expected to be slightly larger than nominal, since an 0. 002” thick layer of kapton was used to prevent the CF from being glued to the mandrel. • Deviations from best fit planes: – A-layer average = -0. 8 µm – B-layer average = +1. 5 µm • Standard deviations: – A-layer = 35 µm – B-layer = 16 µm • Radii above correspond to 100 µm silicon. Actual silicon thickness = 75 µm. Worst deviations: – A-layer = +87 / -54 µm – B-layer = +38 / -34 µm Bill Cooper Vertex Detector Mechanics – 2 October 2007 4

A-Layer Results Bill Cooper Vertex Detector Mechanics – 2 October 2007 5

B-Layer Results Bill Cooper Vertex Detector Mechanics – 2 October 2007 6