排序方式: 共有73条查询结果,搜索用时 0 毫秒
71.
简述了地质统计学的理论和方法,并在此基础上应用大型矿业软件Surpac建立了曼家寨锡锌多金属矿床的矿床数学模型,模拟了锌元素的变异函数,建立了矿床的三维实体模型和品位模型,用克立格法进行了储量计算。 相似文献
72.
广西大厂锡矿黑水沟矿体赋矿层位中发现的中基性火山岩主要为玄武岩、安山岩类岩石,大都属于钙碱性-碱性系列。岩石地球化学特征表明该火山岩可能形成于裂谷环境。在大厂矿区,除了存在传统的燕山晚期花岗岩成矿作用外,至少还存在海西早期海底基性火山-沉积成矿作用和海底喷流热水-沉积成矿作用。 相似文献
73.
具有缓冲层和N型埋层的高压兼容Bi-CMOS工艺的超结LDMOS 总被引:1,自引:1,他引:0
A novel buffer super-junction (S J) lateral double-diffused MOSFET (LDMOS) with an N-type buried layer (NB) is proposed. An N- buffer layer is implemented under the SJ region and an N-type layer is buried in the P substrate. Firstly, the new electric field peak introduced by the p-n junction of the P substrate and the N-type buried layer modulates the surface electric field distribution. Secondly, the N-buffer layer suppresses the substrate assisted depletion effect. Both of them improve the breakdown voltage (BV). Finally, because of the shallow depth of the SJ region, the NB buffer SJ-LDMOS is compatible with Bi-CMOS technology. Simulation results indicate that the average value of the surface lateral electric field strength of the NB buffer SJ-LDMOS reaches 23 V/μm at 15/μm drift length which results in a BV of 350 V and a specific on-resistance of 21 mΩ·cm2. 相似文献