Focused electron beam induced etching of silicon using chlorine.

A new beam-assisted process for removing silicon from a surface in the nanometer scale in a conventional scanning electron microscope is presented. This approach is based on focused electron beam induced etching with pure chlorine gas being used as the precursor. In contrast to the established etching process using a focused ion beam (with or without the addition of a precursor), no amorphization and gallium implanting of the substrate takes place. The observed low etch rates facilitate removal with sub-nanometer precision. No spontaneous etching of silicon as in the case of xenon difluoride was observed. Etch rates of up to 4 nm min( - 1) could be achieved as well as a minimum feature size of below 80 nm. The effect of etching parameters like electron beam energy, electron beam accelerating voltage or pixel spacing were systematically examined. Finally, the underlying etching mechanism in terms of secondary electron interactions and precursor replenishment is discussed.

Implementing the district health system in the framework of primary health care in Pakistan: can the evolving reforms enhance the pace towards the millennium development goals?

There is growing renewed trust in primary health care as the best approach for ensuring equity in the delivery of essential health services. However, Pakistan with one of the most widely spread district health system networks in the region, has not delivered at the expected capacity. A series of health system reform agendas are now stipulated which include the promulgation of an essential health service package, public private partnerships and a people-centred focus. Nevertheless, success of these reforms will hinge on the ability of the three tiers of the government and other stakeholders to work together to improve the overall performance of the district health system. This paper provides an overview of the district health system infrastructure and organization of primary health care services in Pakistan, the evolving governance pattern and the operational significance and merit of health system pillars for effective service implementation.

Implementing the district health system in the framework of primary health care in Pakistan: can the evolving reforms enhance the pace towards the Millennium Development Goals?

There is growing renewed trust in primary health care as the best approach for ensuring equity in the delivery of essential health services. However, Pakistan with one of the most widely spread district health system networks in the region, has not delivered at the expected capacity. A series of health system reform agendas are now stipulated which include the promulgation of an essential health service package, public private partnerships and a people-centred focus. Nevertheless, success of these reforms will hinge on the ability of the three tiers of the government and other stakeholders to work togetherto improve the overall performance of the district health system. This paper provides an overview of thedistrict health system infrastructure and organization of primary health care services in Pakistan, the evolving governance pattern and the operational significance and merit of health system pillars for effective service implementation