• Title/Summary/Keyword: Preston's law

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Prevention in the United States Affordable Care Act

  • Preston, Charles M.;Alexander, Miriam
    • Journal of Preventive Medicine and Public Health
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    • v.43 no.6
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    • pp.455-458
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    • 2010
  • The Affordable Care Act (ACA) was signed into law on March 23, 2010 and will fundamentally alter health care in the United States for years to come. The US is currently one of the only industrialized countries without universal health insurance. The new law expands existing public insurance for the poor. It also provides financial credits to low income individuals and some small businesses to purchase health insurance. By government estimates, the law will bring insurance to 30 million people. The law also provides for a significant new investment in prevention and wellness. It appropriates an unprecedented $15 billion in a prevention and public health fund, to be disbursed over 10 years, as well as creates a national prevention council to oversee the government's prevention efforts. This paper discusses 3 major prevention provisions in the legislation: 1) the waiving of cost-sharing for clinical preventive services, 2) new funding for community preventive services, and 3) new funding for workplace wellness programs. The paper examines the scientific evidence behind these provisions as well as provides examples of some model programs. Taken together, these provisions represent a significant advancement for prevention in the US health care system, including a shift towards healthier environments. However, in this turbulent economic and political environment, there is a real threat that much of the law, including the prevention provisions, will not receive adequate funding.

Dependence of Nanotopography Impact on Fumed Silica and Ceria Slurry Added with Surfactant for Shallow Trench Isolation Chemical Mechanical Polishing

  • Cho, Kyu-Chul;Jeon, Hyeong-Tag;Park, Jea-Gun
    • Korean Journal of Materials Research
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    • v.16 no.5
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    • pp.308-311
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    • 2006
  • The purpose of this study is to investigate the difference of the wafer nanotopography impact on the oxide-film thickness variation between the STI CMP using ceria slurry and STI CMP using fumed silica slurry. The nanotopography impact on the oxide-film thickness variation after STI CMP using ceria slurry is 2.8 times higher than that after STI CMP using fumed silica slurry. It is attributed that the STI CMP using ceria slurry follows non-Prestonian polishing behavior while that using fumed silica slurry follows Prestonian polishing behavior.

Degradation from Polishing Damage in Ferroelectric Characteristics of BLT Capacitor Fabricated by Chemical Mechanical Polishing Process (화학적기계적연마 공정으로 제조한 BLT Capacitor의 Polishing Damage에 의한 강유전 특성 열화)

  • Na, Han-Yong;Park, Ju-Sun;Jung, Pan-Gum;Ko, Pil-Ju;Kim, Nam-Hoon;Lee, Woo-Sun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.236-236
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    • 2008
  • (Bi,La)$Ti_3O_{12}$(BLT) thin film is one of the most attractive materials for ferroelectric random access memory (FRAM) applications due to its some excellent properties such as high fatigue endurance, low processing temperature, and large remanent polarization [1-2]. The authors firstly investigated and reported the damascene process of chemical mechanical polishing (CMP) for BLT thin film capacitor on behalf of plasma etching process for fabrication of FRAM [3]. CMP process could prepare the BLT capacitors with the superior process efficiency to the plasma etching process without the well-known problems such as plasma damages and sloped sidewall, which was enough to apply to the fabrication of FRAM [2]. BLT-CMP characteristics showed the typical oxide-CMP characteristics which were related in both pressure and velocity according to Preston's equation and Hernandez's power law [2-4]. Good surface roughness was also obtained for the densification of multilevel memory structure by CMP process [3]. The well prepared BLT capacitors fabricated by CMP process should have the sufficient ferroelectric properties for FRAM; therefore, in this study the electrical properties of the BLT capacitor fabricated by CMP process were analyzed with the process parameters. Especially, the effects of CMP pressure, which had mainly affected the removal rate of BLT thin films [2], on the electrical properties were investigated. In order to check the influences of the pressure in eMP process on the ferroelectric properties of BLT thin films, the electrical test of the BLT capacitors was performed. The polarization-voltage (P-V) characteristics show a decreased the remanent polarization (Pr) value when CMP process was performed with the high pressure. The shape of the hysteresis loop is close to typical loop of BLT thin films in case of the specimen after CMP process with the pressures of 4.9 kPa; however, the shape of the hysteresis loop is not saturated due to high leakage current caused by structural and/or chemical damages in case of the specimen after CMP process with the pressures of 29.4 kPa. The leakage current density obtained with positive bias is one order lower than that with negative bias in case of 29.4 kPa, which was one or two order higher than in case of 4.9 kPa. The high pressure condition was not suitable for the damascene process of BLT thin films due to the defects in electrical properties although the better efficiency of process. by higher removal rate of BLT thin films was obtained with the high pressure of 29.4 kPa in the previous study [2].

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