一种气(Ga)-固(Al掺杂氧化物)-固(Si)掺杂新工艺

针对制造高压晶闸管p型杂质扩散工艺的不足,进行了开管式受主双质掺杂技术的研究.通过大量试验和工艺论证,研制成一种气(Ga) -固(Al掺杂氧化物) -固(Si)掺杂新工艺.经应用证明,该掺杂技术能明显提高器件的电参数一致性、综合性能和成品率,为电力半导体器件研究和生产开辟了一条可行的受主双质掺杂新工艺     

Ge/Si量子点的生长研究进展

要有效应用SK模式生长的Ge量子点,必须实现Ge量子点的位置可控并且进一步缩小Ge量子点的尺寸.阐释了这方面的研究进展,特别对图形衬底生长Ge量子点,利用Si表面的自组织性在错切割的邻晶面衬底上生长有序Ge岛,表面杂质诱导成岛这三个方面的进展加以介绍分析.     

高温超导YBa2Cu3O7薄膜的颗粒,杂相生长机制研究

ＹＢａ２Ｃｕ３Ｏ７（ＹＢＣＯ）高温超导薄膜是重要的超导电子器件应用的材料，它们的质量对器件的运行性能至关重要。薄膜表面的颗粒使表面微波性能变坏，但有些生长在ＹＢＣＯ薄膜基体内部的小颗粒，会使薄膜的临界电流密度升高。     

30 V UMOS中影响导通电阻平坦度的因素分析

功率MOSFET作为开关器件时,导通电阻的平坦度是衡量其性能的重要参数。研究影响导通电阻平坦度的因素,并对其进行优化,有助于改善器件的性能。低压UMOS中,沟道电阻是导通电阻的主要部分。文章以沟道电阻为分析对象,利用公式分析影响因素,通过Sentaurus TCAD仿真验证了导通电阻平坦度的变化趋势。通过改变P型基区离子注入剂量和栅氧层厚度进行仿真。仿真结果表明,通过减小栅氧层厚度和减少P型基区注入剂量,可获得较好的导通电阻平坦度。     

外延阻挡杂质带探测器的抗反射

传统外延阻挡杂质带探测器由于其材料物性和特殊的结构设计存在很强的反射,这些能量损失非常不利于器件的探测性能.报道了一种类光栅双层超构表面微结构阵列,并将此人工微结构引入到外延阻挡杂质带红外探测器以抑制对入射光的反射.实验结果显示,具有超构表面微结构阵列的器件在波长30μm处反射率低于3％,在25.3～32.2μm波段范...     

Enhanced Electron Mobility Due to Dopant‐Defect Pairing in Conductive ZnMgO

The increase of the band gap in Zn_1‐xMg_xO alloys with added Mg facilitates tunable control of the conduction band alignment and the Fermi‐level position in oxide‐heterostructures. However, the maximal conductivity achievable by doping decreases considerably at higher Mg compositions, which limits practical application as a wide‐gap transparent conductive oxide. In this work, first‐principles calculations and material synthesis and characterization are combined to show that the leading cause of the conductivity decrease is the increased formation of acceptor‐like compensating intrinsic defects, such as zinc vacancies (V_Zn), which reduce the free electron concentration and decrease the mobility through ionized impurity scattering. Following the expectation that non‐equilibrium deposition techniques should create a more random distribution of oppositely charged dopants and defects compared to the thermodynamic limit, the paring between dopant Ga_Zn and intrinsic defects V_Zn is studied as a means to reduce the ionized impurity scattering. Indeed, the post‐deposition annealing of Ga‐doped Zn_0.7Mg_0.3O films grown by pulsed laser deposition increases the mobility by 50% resulting in a conductivity as high as σ = 475 S cm^‐1.     

非掺杂InP的低温光致发光研究

研究了2K低温下非有意掺杂InP单晶的光致发光谱,对近带边的辐射跃迁进行了仔细分析,报道了InP单晶在大功率光激发时束缚于中性施主的激子跃迁发光相对减弱、而束缚于中性受主的激子跃迁发光相对增强的现象,并探讨了其机制,确认了材料中存在Mg、Zn等残余受主杂质,并计算得到Mg受主的离化能为41.5meV.     

Effect of Annealing Ambient on the Self-Formation Mechanism of Diffusion Barrier Layers Used in Cu(Ti) Interconnects

Copper (titanium) [Cu(Ti)] films with low titanium (Ti) concentration were found to form thin Ti-rich barrier layers at the film/substrate interfaces after annealing, which is referred to as self-formation of the barrier layers. This Cu(Ti) alloy was one of the best candidates for interconnect materials used in next-generation ultra-large-scale integrated (ULSI) devices that require both very thin barrier layers and low-resistance interconnects. In the present paper, in order to investigate the influences of annealing ambient on resistivity and microstructure of the Cu alloys, the Cu(7.3at.%Ti) films were prepared on the SiO₂ substrates and annealed at 500°C in ultra-high vacuum (UHV) or argon (Ar) with a small amount of impurity oxygen. After annealing the film at 500°C in UHV, the resistivity was not reduced below 16 μΩ-cm. Intermetallic compounds of Cu₄Ti were observed to form in the films and believed to cause the high resistivity. However, after subsequently annealing in Ar, these compounds were found to decompose to form surface TiO _x and interfacial barrier layers, and the resistivity was reduced to 3.0 μΩ-cm. The present experiment suggested that oxygen reactive to titanium during annealing played an important role for both self-formation of the interfacial barrier layers and reduction of the interconnect resistivity.     

用于远红外探测的Si:P阻挡杂质带红外探测器研制

提出了全外延技术方案制备阻挡杂质带薄膜,避免了离子注入制备背电极层影响外延薄膜质量的技术难点.基于硅器件工艺设计制作了Si:P阻挡杂质带红外探测器.测量了器件的光电流响应谱和暗电流特性曲线,指认了叠加在光电流响应谱上的尖锐杂质峰对应阻挡层中磷原子的杂质跃迁.研究了器件在低温下小偏压范围内的暗电流起源.通过对计算结果分析,排除了该区域暗电流起源于热激发电导和跳跃式电导的可能,指出暗电流来自器件对冷屏的光电响应.器件工作温度5 K,工作偏压1.6 V时,响应波段覆盖2.5~40μm,峰值波长28.8μm,峰值响应率20.1 A/W,峰值探测率3.7×1013cm·Hz1/2/W(背景光子通量低于1013ph/cm2·s).