【作者】 殷允超；

【导师】 黄秋萍；

【作者基本信息】 苏州大学 ， 电子与通信工程， 2011， 硕士

【摘要】 功率MOSFET是将微电子技术和电力电子技术融合起来的新一代功率半导体器件。因其具有输入阻抗高、开关速度快、输出电流大和热稳定性好、安全工作区宽等优点,在电源保护、电源开关、DC/DC变换器和同步整流等电子设备中得到广泛应用。本文给出了一种带有ESD保护栅结构的Trench MOSFET的设计流程。和普通MOSFET相比,其创新之处在于植入了ESD保护结构,使其抗ESD能力相比普通MOSFET显著提高。本文的目的是在达到设计目标的同时尽量减少光刻版的层数,降低单位面积的导通电阻,从而有效控制成本。第一部分是研究背景,包括功率MOSFET和ESD保护型功率MOSFET的发展、应用以及市场前景等。第二部分是理论基础,介绍了Trench MOSFET和ESD的理论知识,提出了在栅极区制造ESD保护结构方法,此方法可以有效控制芯片面积。第三部分是工程实践,首先通过经典理论公式推导出外延片规格;终端结构使用场板、多晶硅场限环和截止环的复合结构;ESD保护二极管先P型掺杂再N型注入的顺序使N注入可以和N+源区同时形成,减少了光刻版的数量;接下来使用Tsuprem4和Medici模拟软件初步定出流程基本条件,通过工程批的流片和封装数据对模拟条件进行校准和调整,最终的结果完全满足了预期的设计目标。更多还原

【Abstract】 Power MOSFETs are an important class of discrete devices for a variety of power conversion applications because of high input impedance, high switching frequency,large output current, good thermal stability and large safe operating area.It is being widely applied in the electronics equipments such as buttery protection , switching-mode power supply, DC-DC converter , synchronous rectifiers and etc.In this paper, a gate ESD protected Trench MOSFET is designed. The innovation is that this kind of Trench MOSFET get better ability on enduring ESD than normal MOSFET. The purpose of this article is to reduce the cost by decreasing the mask quantity and reducing RDSON per unit area.The first part of this article is the research background. It includes the development, application and market prospects of power MOSFET and the ESD protected MOSFET. The second part is the theory including the basic theory of Trench MOSFET and ESD. Making ESD structure at the Gate PAD field is also be presented, this method can reduce die size effectively. The third part is the engineering practice. firstly, the Epi spec is get by a academic expressions; the terminal introduce a special structure with Field-board, poly Guard-ring and Stop-ring together; manufacturing ESD diode on the method of P type doping first and then N type implant so that N type implant can be formed at the same time with N+ source implant, by this way we can reduce one mask layer; Tsuprem4 and Medici software are used to get the basic condition of the process, after analyzing the result of engineering lot CP data, FT data and HBM ESD data, then the best design is selected which achieves expected aim very well.更多还原