Development of fabrication technology for thinned “3D PIXEL“
Radiation sensors
— Single-sided processing of 150 mm wafers (23 pcs) using in-house Deep
Reactive Ion Etch (DRIE) fabrication technology
— Total budget: 2 MNOK
— Timeframe: Starting 2014Q3, 26 weeks onward
>>
— Deliverables: Processed wafers shipped to CERN
— Technical specification:
— Material Procurement:
— Sensor substrate wafers, 300 um thick, 150 mm diameter P-type high-
>> resistivity float zone
— Handle wafers, 300 um thick, 150 mm diameter (mechanical quality)
>>
— Mask design and procurement (8 masks total):
>> - N+ electrodes (DRIE and POLY)
>> - P+ electrodes (DRIE and POLY)
— Test metal layer
— Final metal layer
— Sensor fabrication steps:
>> - Substrate P-spray implantation
— Sensor/handle wafer bonding
— Thinning to 50, 100 um
— High aspect ratio DRIE fabrication of 3D electrode structures
— N+, P+ implantation and polysilicon filling in separate steps
>> - Contact openings, metal patterning and passivation
— Quality control and testing:
— Evaluation of standard test diode structures and process control monitors
— Evaluation of test metal layer