Mic-in-CMOS: CMUT as a Sealed-Gap Capacitive Microphone

2020 IEEE International Ultrasonics Symposium (2020 : Las Vegas; United States)The design and production of a CMOS compatible, watertight and ingress-proof CMUT (capacitive micromachined ultrasonic transducer) microphone, mic-in-CMOS, with vacuum-gap is described. We present an analytical model-based approach for the design of mic-in-CMOS, where a basis for quantitative comparison of performance trade-offs is provided. The sealed vacuum gap of the mic-in-CMOS is basically a lossless sensor, free of mechanical noise. Its SNR is determined by the noise of the pre-amplification electronics (the noise contributor in a CMUT with vacuum gap is essentially the radiation resistance, which is less than 0 dBA for audio band for a 1 mm2 device). The design of mic-in-CMOS involves many multilateral trade-offs such as gap height vs membrane thickness vs sensitivity vs need for linear operation vs bias voltage and atmospheric depression, to name few. The mic-in-CMOS design can be mass produced using CMOS film stacks only, as such the fabrication process can be carried out entirely in a CMOS processes production line complemented with CMOS compatible post-processing approaches. Mic-in-CMOS has the advantage of low production cost with minimal packaging requirement and on-die EMI / EMC. © 2020 IEEE

Gendered property and labour relations in agriculture: implications for social change in Turkey

By investigating the implications of gendered property and labour relations in agriculture for socio-economic transformation, this article extends development theories and contributes to feminist analysis of unpaid family labour. Drawing on the case of Turkey, it demonstrates that gendered patterns of agriculture limit women’s mobility, access to education, and paid employment in non-agricultural sectors. Using the qualitative and quantitative methods, the paper finds that patriarchal property and labour relations prevent the movement of labour from agriculture to non-agricultural sectors, constrain labour supply, and increase subsistence earnings thereby putting upward pressure on urban wages