• Title/Summary/Keyword: Butting contact

Search Result 3, Processing Time 0.015 seconds

A Study on Characteristics of column fails in DDI DRAM (DDI DRAM에서의 Column 불량 특성에 관한 연구)

  • Chang, Sung-Keun;Kim, Youn-Jang
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.9 no.6
    • /
    • pp.1581-1584
    • /
    • 2008
  • In dual-polycide-gate structure with butting contact, net doping concentration of polysilicon was decreased due to overlap between $n^+$ and $p^+$ and lateral dopant diffusion in silicide/polysilicon layers. The generation of parasitic Schottky diode in butting contact region is attributed both to the $CoSi_2$-loss due to $CoSi_2$ agglomeration and to the decrease in net doping concentration of polysilicon layer. Parasitic Schottky diode reduces noise margin of sense amplifier in DDI DRAM, which causes column fail. The column fail could be reduced by physical isolation of $n^+/p^+$ polysilicon junction or suppressing $CoSi_2$ agglomeration by using nitrogen implantation into $p^+$ polysilicon before $CoSi_2$ formation.

Analysis of effect of parasitic schottky diode on sense amplifier in DDI DRAM (DDI DRAM의 감지 증폭기에서 기생 쇼트키 다이오드 영향 분석)

  • Chang, Sung-Keun;Kim, Youn-Jang
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.11 no.2
    • /
    • pp.485-490
    • /
    • 2010
  • We propose the equivalent circuit model including all parasitic components in input gate of sense amplifier of DDI DRAM with butting contact structure. We analysed the effect of parasitic schottky diode by using the proposed model in the operation of sense amplifier. The cause of single side fail and the temperature dependence of fail rate in DDI DRAM are due to creation of the parasitic schottky diode in input gate of sense amplifier. The parasitic schottky diode cause the voltage drop in input gate, and result in decreasing noise margin of sense amplifier. therefore single side fail rate increase.

Mating and Incidental Activities of Ram (Ovis aries) When Exposed to Ewe(s) and Competitor Ram in Pen Mating Condition

  • Patel, M.;Das, N.;Pandey, H.N.;Yadav, M.C.;Girish, P.S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.18 no.4
    • /
    • pp.463-469
    • /
    • 2005
  • An attempt was made to analyze the factors affecting mating performance of rams in pen mating systems. Due to many types of social interactions, mating performance of rams may decrease or increase. Six intact Muzaffarnagari rams were used and divided into three dominant subordinate pairs by food and ewe competition test. For dominant rams subordinate ram became competitor and vice versa. In the first experiment, ram was exposed to ewe but the competitor ram was kept outside the pen with the facility of visibility only. In the second experiment each ram was exposed to ewe along with the competitor ram and in third experiment ram was exposed to ewes (two) along with competitor ram in observation pen. Recordings of different mating and agonistic behaviour were done in all the experiments. It was found that subordinate ram's mating behaviour was inhibited by mere presence of a dominant ram out side without physical contact. However, when ram exposed to oestrus ewe(s) along with competitor ram, both dominant and subordinate rams spent much of their time in guarding activities instead of mating. In addition dominant ram tried to curtail the subordinate ram mating by agonistic interaction like fight and butting. Different guarding activities were observed either as active or passive type depending on level of dominanace. It was concluded that in a limited space the interaction of two or more rams might affect the number of services adversely.