In our previous works, we have studied the fabrication process and characterization of single cell micro-bolometers based on germanium thin films deposited by low frequency (LF) PECVD technique at low temperature and fully compatible with the IC fabrication technology. We have demonstrated promising properties of those devices for further development of IR imaging systems [1-2]. In this work, we report the study and characterization of the fabrication process of a lineal array of 32 un-cooled micro-bolometers. We have used surface micro-machining techniques for the array fabrication onto a silicon wafer. The micro-bolometers in the array have a "bridge type" configuration. In this case, a SiN{sub}x supporting film is suspended 2.5 μm from the substrate by two legs, which form the bridge and provide sufficient thermo-isolation to the thermo-sensing layer. The thermo-sensing layer was deposited on the bridge by using LF PECVD. The a-Ge{sub}xSi{sub}y:H film used in this devices showed high activation energy E{sub}a = 0.34 eV, providing high thermal coefficient of resistance, TCR=α=0.043 K{sup}(-1) and improved but still high resistance. We studied the effect of the addition of boron to the a-Ge{sub}xSi{sub}y:H film deposition process, for reducing its undesirable high resistance and, the resulting layer (a-Ge{sub}xB{sub}ySi{sub}z:H) is used as thermo-sensing film in the micro-bolometers arrays. The active area of the cell in the array is A{sub}b=70×66 μm{sup}2 and the area of the array including interconnection lines and pads is A{sub}A=1600×3120 μm{sup}2. The temperature dependence of conductivity σ(T), current-voltage characteristics I(U), and spectral noise density have been measured in the array and the main figures of merit such as, responsivity and detectivity have been obtained.
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