Novel Si drift detectors arrays with customer-design, low current (low heat, low power) spiral biasing adapter and double-metal interconnections

A novel Si drift detector (SDD) array (array size: NxM) using a customer-design, low current (low heat) biasing adapter and double-metal interconnections between the single cells in the array is proposed here. The spiral biasing adapter (SBA) itself is also a new concept with the following characteristics and advantages: 1) it is customer-design for any desired geometry of SDD single cell with minimum current and minimum drift time of carriers; 2) it has the spiral shaped ionimplants that define the desired voltage profile according to calculations; 3) the radius dependence of the pitch (pSBA(r)) of the spiral is the same as that of the SDD single cell (p_SBA (r))=P_SDD(r)), which in general varies with radius; 4) the width of the implanted spiral (WSBA(r)) that varies with radius does not have to equal to that of the SDD single cell (W_SBA(r)≠W_SDD(r)), and can be made small to minimize the current; 5) it is processed on the same wafer of SDD array; 6) only one SBA chip/side is needed for one SDD array to define the voltage profiles on the front side and backside (two SBA chips for double-side SDD array, one SBA chip for SDD array with uniform backside bias); and 7) the connection of the SBA chip and the SDD array can be either double metal (most convenient, SBA and SDD are attached) or wire bonding (SBA chip is diced off from the SDD array, no heat on the SDD array). The geometry of a single SDD cell is defined by concentric rings of ion-implants (p_SDD(r)=P_SBA(r)) with maximum width (W_SDD(r))>W_SBA(r)) to minimize surface current. The surface potential profiles of the leading single SDD cell are defined by the SBA chips provided by wire bond or second metal interconnections, while those of the rest of single SDD cells in the