Within only the last decade, usage of mobile phones and many other electronic devices with high speed wireless RF connection is rapidly increasing. Modern life requires reliable, quick and high-quality information connections, which explains the widely spreading craze for electronic mobile devices of various types. The vast technological advances we are witnessing in electronics, electro-optics, and computer science have profoundly affected our everyday lives.Meanwhile, safety concerns regarding the biological effects of electromagnetic (EM) radiation have been raised, in particular at a low level of exposure which we everyday experience. A variety of waves and signals have to be considered such as different sine waves, digital signals used in radio, television, mobile phone systems and other information transfer systems. The field around us has become rather complicated and the "air space is getting more and more dense with RF. The establishing of safety recommendations, law norms and rules augmented by adequate measurements is very important and requires quite an expertise.But as many scientific researches suggest, what we are currently witnessing is very likely to generate a great public danger and a bad influence over the human body. There are many health organisations warning the public for possible development of cancer, mental and physical disorders etc [7,8]. These suggestions are quite serious and should not be neglected by the official bodies and the test laboratories.In the following work, the effects of electromagnetic field over a virtual model of a human head have been simulated in the frequency range from 900 MHz to 1800 MHz (commonly created in the real life by mobile GSM system) with the help of the program MEFiSTo 2D Classic [1]. The created virtual models using the 2D simulation&computation software proved that the use of new high tech nanotextile materials for shielding layers around the human body can reduce the effects of EM fields dramatically if chosen properly according to the area of application.

We have fabricated and tested GMR magnetic sensors that operate in the CPP mode. This work is a continuation of the ultra-high density magnetic sensor research introduced a t INTERMAG 96. We have made two significant modifications to the process sequence. First, contact to the sensor is made through a metal conduit deposited in situ with the multilayers. This deposition replaces electroplating. T h i s configuration ensures a good electrical interface between the top of multilayer stack and the t o p contact, and a continuous, conductive current path to the sensor. The consequences of t h i s modification are an increase in yield of operational devices to 290% per wafer and a significant reduction of the device resistance to 4560 mil and of the uniformity of the device resistance to 1 3 % . Second, the as-deposited multilayer structure h a s been changed from [Cu 30 A/Co 20 A118 (third peak) to [Cu 20.5 &CO 12 63130 (second peak) t oincrease the GMR response. The best second peak CPP GMR response from a single device is 39%. The sensitivity of that device is 0.13 %/Oe.

Abstract-A large giant magnetoresistance (GMR) value of 7.5% has been measured in simple NiFeCo(l)lCu/NiFeCo(2) sandwich films grown on a 30 A Cr seed layer. This spin-valve GMR effect is consistent with the differential switching of the two NiFeCo layers due to an enhanced coercivity of the NiFeCo(1) layer grown on the Cr seed layer. A change in growth texture of the NiFeCo(1) layer from fee (111) to bee (110) crystallographic orientation leads to an increase in magnetic anisotropy and and an enhancement in coercivity.The GMR value increases to 8.7% when a thin CoFe interfacial enhancing layer is incorporated. Further enhancement in GMR values up to 14% is seen in the sandwich films by nanooxide layer formation. The specular reflection at oxide/magnetic layer interface further extends the mean free path of spinpolarized electrons.

No abstract

No abstract