發(fā)布時間：2018-09-12 07:28

【摘要】：作為地殼中儲量最大的半導(dǎo)體材料,硅材料具有良好的半導(dǎo)體特性,廣泛應(yīng)用于電子信息等領(lǐng)域。硅分立器件,作為一種半導(dǎo)體器件領(lǐng)域的重要組成部分,在汽車電子、工業(yè)自動化與3G通信等方面具有重要的應(yīng)用意義,并且目前其工藝技術(shù)成熟、器件可靠性高、生產(chǎn)成本低。而作為硅分立器件家族中的一員,硅恒流二極管的恒流特性好、價格低、使用簡便,可提供穩(wěn)定的電流輸出,是實(shí)現(xiàn)各種電子設(shè)備的恒流源、穩(wěn)壓源及保護(hù)電路的重要器件之一。然而,由于目前的恒流二極管存在起始電壓大、恒流區(qū)域窄、動態(tài)阻抗小等問題,因此其應(yīng)用范圍受到了一定限制。 本文基于恒流二極管的應(yīng)用背景和價值,綜述了國內(nèi)外這一領(lǐng)域的發(fā)展現(xiàn)狀。根據(jù)恒流二極管的工作原理,結(jié)合半導(dǎo)體物理和半導(dǎo)體器件物理基礎(chǔ)知識,結(jié)合器件設(shè)計(jì)要求,初步設(shè)計(jì)了器件的結(jié)構(gòu)參數(shù)。利用數(shù)值模擬方程和器件物理模型,通過數(shù)值模擬方法模擬出該器件的I-V特性曲線,與設(shè)計(jì)要求進(jìn)行對比并分析原因。然后通過對一些器件結(jié)構(gòu)參數(shù),如溝道摻雜濃度、溝道寬度、溝道長度、柵漏間距等進(jìn)行優(yōu)化,改善了初始設(shè)計(jì)的恒流二極管的恒流特性,恒定電流由5.5×10-6A提高到了6.7×10-6A,擊穿電壓由35V提高到了54V。為降低PN結(jié)邊緣的尖峰電場,本文又將場板技術(shù)應(yīng)用于優(yōu)化后的結(jié)構(gòu),結(jié)果發(fā)現(xiàn)恒流二極管的擊穿電壓由54V提高到60V,提高幅度高達(dá)1O%。接著,本文又模擬并分析了加場板結(jié)構(gòu)的電流溫度系數(shù)、動態(tài)阻抗等特性,電流溫度系數(shù)為-0.26%/℃,動態(tài)阻抗為60KΩ。最后,本文給出器件的工藝流程及版圖,并簡要介紹了器件主要工藝。 研究結(jié)果表明,恒流二極管特性參數(shù)理論計(jì)算公式與器件的實(shí)際特性較為符合。恒流二極管的各項(xiàng)參數(shù),如起始電壓、恒定電流和擊穿電壓等,需要折中選取。場板結(jié)構(gòu)的應(yīng)用對恒流二極管的擊穿特性有一定的改善作用。應(yīng)用場板技術(shù)后的結(jié)構(gòu)恒流特性較好且恒流值大,恒流區(qū)域?qū)?起始電壓小,擊穿電壓較同類型產(chǎn)品大,適用于高精度、大電流領(lǐng)域應(yīng)用。
[Abstract]:As the largest semiconductor material in the earth's crust, silicon has good semiconductor properties and is widely used in electronic information and other fields. Silicon discrete devices, as an important part of semiconductor devices, have important application significance in automotive electronics, industrial automation and 3G communication. Low production cost. As a member of the silicon discrete device family, silicon constant-current diode has good constant-current characteristic, low price, easy to use, and can provide stable current output. It is a constant current source for various electronic devices. One of the important devices of voltage regulator and protection circuit. However, the current constant-current diodes have some problems, such as large initial voltage, narrow constant current region and small dynamic impedance, so their application scope is limited. Based on the application background and value of constant-current diodes, this paper summarizes the development of this field at home and abroad. According to the working principle of constant-current diode, combined with the basic knowledge of semiconductor physics and semiconductor device physics, combined with the device design requirements, the structure parameters of the device are preliminarily designed. The I-V characteristic curve of the device is simulated by the numerical simulation equation and the physical model of the device. The results are compared with the design requirements and the reasons are analyzed. Then, by optimizing some device structure parameters, such as channel doping concentration, channel width, channel length, gate leakage distance, etc., the constant current characteristics of the initial design constant current diode are improved. The constant current is increased from 5.5 脳 10 ~ (-6) A to 6.7 脳 10 ~ (-6) A, and the breakdown voltage is increased from 35 V to 54 V. In order to reduce the peak electric field at the edge of the PN junction, the field plate technique is applied to the optimized structure. It is found that the breakdown voltage of the constant current diode is increased from 54 V to 60 V, and the amplitude of the increase is as high as 1 O. Then, the current temperature coefficient and dynamic impedance of the structure are simulated and analyzed. The current temperature coefficient is -0.26 / 鈩，

本文編號：2238323