2008半导体物理期末考试试卷A-参考答案与评分标准.doc

marketing strict internal cost control, business and innovation performance. -Increasing electricity access, price increase, electricity supply is guaranteed. In 2012, the company with coal inventory, get rewards of Jiangsu provincial government power to 266 million kWh. Through the small and bilateral trade, access to electricity 1.695 billion kWh, seeking removal compensation when the power 50 million-kilowatt, 116% market share in Jiangsu Province ranked first in the same capacity, the same type units. Company closely tracked coal linkage policies on July 1 and August 20 respectively increase prices 2.08 minutes and 2.5 points, profitability increased significantly. 公 . Job grading, remuneration of labour agreements into long-term contract workers compensation system, stimulating the enthusiasm of the staff. -Further strengthening of human resources management. Full implementation of the performance appraisal regulations, incentive effect. Complete the reserve cadre evaluation and selection, produced 10 primary reserve cadres and 11 secondary reserve cadres. Implementation of operation staff induction gang system, 14 staff posts be promoted. Strengthening the cultivation of professional technical leaders, selected coverage 9 13 factory-level professional and technical leaders. To enhance staff skills training, 8 staff technicians. Labor contract law compliance, contracts of up to 100%. -Star team-building to advance further. Establish a holding system implementation, and promoting the whole team-building goals, strengthen group management. Team building into a performance review, promoting the construction of the star team depth. This year, respectively, 1 track, 4 team four star rated five-star by Datang and the team. Four, insists on six cultural construction of harmonious development, really good job of party construction and the independent Commission against corruption, strengthening the humanistic care and psychological counseling, the enterprise culture construction to a new level. -Building of enterprise culture is fruitful. Companies adhere to the Shenhua lead of corporate culture, culture of responsibility at the core, to safety culture, a culture of learning, ethical culture, cost culture culture system-assisted, through various cultural integration, has boosted business centre, this year has won the Chinese cultural management advanced unit, National Advanced Unit in the building of enterprise culture of reform and opening up 30 and other honorary titles. The liability of the company culture: solving management problems of corporate culture project was awarded the CEC national electric power enterprise culture achievement award of excellence. The accident early warning and prevention system was rated as Chinas power of innovation management, innovation management of electric power enterprise in Jiangsu Province. -Party and the independent Commission against corruption continues to strengthen. Was carried out to maintain学院 姓名 学号 任课老师 选课号 密封线以内答题无效电子科技大学二零零 七 至二零零 八 学年第 一 学期期 末 考试一、选择填空（22分）1、在硅和锗的能带结构中，在布里渊中心存在两个极大值重合的价带，外面的能带（ B ），对应的有效质量（ C ），称该能带中的空穴为( E )。A. 曲率大； B. 曲率小；（二阶导数小） C. 大；D. 小； E. 重空穴；F. 轻空穴2、如果杂质既有施主的作用又有受主的作用，则这种杂质称为（ F ）。 A. 施主 B. 受主 C.复合中心 D.陷阱 F. 两性杂质3、在通常情况下，GaN呈（ A ）型结构，具有（ C ），它是（ F ）半导体材料。A. 纤锌矿型； B. 闪锌矿型； C. 六方对称性；D. 立方对称性；E.间接带隙； F. 直接带隙。4、同一种施主杂质掺入甲、乙两种半导体，如果甲的相对介电常数r是乙的3/4， mn*/m0值是乙的2倍，那么用类氢模型计算结果是（ D ）。A.甲的施主杂质电离能是乙的8/3，弱束缚电子基态轨道半径为乙的3/4B.甲的施主杂质电离能是乙的3/2，弱束缚电子基态轨道半径为乙的32/9C.甲的施主杂质电离能是乙的16/3，弱束缚电子基态轨道半径为乙的8/3D.甲的施主杂质电离能是乙的32/9，的弱束缚电子基态轨道半径为乙的3/85、.一块半导体寿命=15s，光照在材料中会产生非平衡载流子，光照突然停止30s后，其中非平衡载流子将衰减到原来的（ C ）。 A.1/4 ； B.1/e ； C.1/e2 ； D.1/26、对于同时存在一种施主杂质和一种受主杂质的均匀掺杂的非简并半导体，在温度足够高、ni /ND-NA/ 时，半导体具有 （ B ） 半导体的导电特性。 A. 非本征 B.本征 7、在室温下，非简并Si中电子扩散系数D与有如下图 （C ） 所示的最恰当的依赖关系： 8、在纯的半导体硅中掺入硼，在一定的温度下，当掺入的浓度增加时，费米能级向（ A ）移动；当掺杂浓度一定时，温度从室温逐步增加，费米能级向( C )移动。A.Ev ； B.Ec ； C.Ei； D. EF9、把磷化镓在氮气氛中退火，会有氮取代部分的磷，这会在磷化镓中出现（ D ）。A.改变禁带宽度 ； B.产生复合中心 ； C.产生空穴陷阱 ； D.产生等电子陷阱。10、对于大注入下的直接复合，非平衡载流子的寿命不再是个常数，它与（ C ）。A.非平衡载流子浓度成正比 ； B.平衡载流子浓度成正比； C.非平衡载流子浓度成反比； D.平衡载流子浓度成反比。11、杂质半导体中的载流子输运过程的散射机构中，当温度升高时，电离杂质散射的概率和晶格振动声子的散射概率的变化分别是（ B ）。 A.变大，变小 ； B.变小，变大； C.变小，变小； D.变大，变大。12、如在半导体的禁带中有一个深杂质能级位于禁带中央，则它对电子的俘获率（ B ）空穴的俘获率，它是（ D ）。 A.大于 ； B.等于； C.小于； D.有效的复合中心； E. 有效陷阱。13、在磷掺杂浓度为21016cm-3的硅衬底（功函数约为4.25eV）上要做出欧姆接触，下面四种金属最适合的是（ A ）。A. In (Wm=3.8eV) ； B. Cr (Wm=4.6eV)； C. Au (Wm=4.8eV)； D. Al (Wm=4.2eV)。14、在硅基MOS器件中，硅衬底和SiO2界面处的固定电荷是（ B ），它的存在使得半导体表面的能带（ C ）弯曲，在C-V曲线上造成平带电压（ F ）偏移。 A.钠离子 ； B.过剩的硅离子； C.向下； D.向上； E. 向正向电压方向； F. 向负向电压方向。二、简答题：（5+4+6=15分）跃迁过程1 (0.5分)Ec (0.5分)Ec (0.5分)1、用能带图分别描述直接复合、间接复合过程。（4分）跃迁过程2 (0.5分)Ec (0.5分)Et（或：杂质或缺陷能级）(0.5分)Ec (0.5分)跃迁过程Ec (0.5分)2、对于掺杂的元素半导体Si、Ge中，一般情形下对载流子的主要散射机构是什么？写出其主要散射机构所决定的散射几率和温度的关系。（4分）答：对掺杂的元素半导体材料Si、Ge，其主要的散射机构为长声学波散射（1分）和电离杂质散射其散射几率和温度的关系为：声学波散射：，电离杂质散射：（根据题意，未含Ni也可）3、如金属和一n型半导体形成金属半导体接触，请简述在什么条件下，形成的哪两种不同电学特性的接触，说明半导体表面的能带情况，并画出对应的I-V曲线。（忽略表面态的影响）（6分）答：在金属和n型半导体接触时，如金属的功函数为Wm, 半导体的功函数为Ws。当WmWs时，在半导体表面形成阻挡层接触，是个高阻区，能带向上弯曲；（2分）当WmWs时，在半导体表面形成反阻挡层接触，是个高电导区，能带向下弯曲；（2分）对应的 I-V曲线分别为：VI VI（1分） （1分）三、在时，某器件显示出如下的能带图：（6+4+4=14分） （）平衡条件成立吗？试证明之。（6分）i答：成立。（4分）因为费米能级处处相等的半导体处于热平衡态（即 ）（2分）或 EFn=EFp=EF （2分）或 np=ni2 （2分）或 J=0 （2分）（）在何处附近半导体是简并的？（4分） 答：在靠近L附近 （4分）或 分为三个区域，每个区各为 2分或 2L/3xL（半对） 2分（）试推导流过x=x1处的电子的电流密度表达式？（4分）答： 四、一束恒定光源照在n型硅单晶样品上，其平衡载流子浓度n0=1014cm-3，且每微秒产生电子空穴为1013cm-3。如n=p=2s，试求光照后少数载流子浓度。（已知本征载流子浓度ni=9.65109cm-3）(5分)解：在光照前：光照后：五、在一个均匀的n型半导体的表面的一点注入少数载流子空穴。在样品上施加一个50V/cm的电场，在电场力的作用下这些少数载流子在100s的时间内移动了1cm，求少数载流子的漂移速率、迁移率和扩散系数。（kT=0.026eV）(6分)解：在电场下少子的漂移速率为：迁移率为： 扩散系数为： 六、 掺杂浓度为ND=1016cm-3的n型单晶硅材料和金属Au接触，忽略表面态的影响，已知：WAu=5.20eV, n=4.0eV, Nc=1019cm-3,ln103=6.9 在室温下kT=0.026eV, 半导体介电常数r=12, 0=8.85410-12 F/m，q=1.610-19 库，试计算：(4+4+4=12分) 半导体的功函数；（4分） 在零偏压时，半导体表面的势垒高度，并说明是哪种形式的金半接触，半导体表面能带的状态； 半导体表面的势垒宽度。（4分）解：由得： （1分） （1分） 在零偏压下，半导体表面的势垒高度为：对n型半导体，因为WmWs，所以此时的金半接触是阻挡层（或整流）接触（1分），半导体表面能带向上弯曲（或：直接用能带图正确表示出能带弯曲情况）（1分）。 势垒的宽度为：（2分） 七、T=300 K下，理想MOS电容，其能带图如下图所示。所施加的栅极偏压使得能带弯曲，在Si-SiO2界面EF=Ei。Si的电子亲合势为4.0 eV ，Nc=1019cm-3。利用耗尽近似，回答下列问题：（5+5+5+5+6=26分）EFmEcEvx0.29eV0.59 eVEiEFs （1.5分） （1.5分）1. 半导体中达到了平衡吗？为什么？（5分）答：达到了平衡。因为半导体中EF处处相等（或EFn=EFp=EF，或np=ni2， 或J=0 ）。2. 求出半导体Si-SiO2界面EF=Ei处的电子浓度？同时绘出与该能带图对应的定性电荷块图。(1分) (0.5分) (0.5分)或 电荷块图见上图（评分标准在电荷块图下方）3. 求出ND？（5分）4. 写出VG详细表达式？（5分） 或 如果两个n型半导体构成的MOS结构除了器件1是Al栅，器件2是Au栅，其它参数都相同，将导致这两个MOS结构的高、低频C-V特性曲线发生什么定性变化？试绘出定性高、低频C-V特性曲线。已知WAl=4.25 eV，WAu=4.75 eV。（6分）（1）VFB(Al)0 或：直接在C-V图中VG坐标上明确标出VFB(Al)位于VG坐标轴负方向（1分），VFB(Au) 位于VG坐标轴正方向（1分）（2）判题时请注意，如果考生将两个C-V曲线分别绘在两个坐标图中，注意VFB(Al)是否位于VG坐标轴负方向（1分）、VFB(Au) 是否位于VG坐标轴正方向Al栅C-V：2分（高频C-V 1分+低频C-V 1分）Au栅C-V：2分（高频C-V 1分+低频C-V 1分）Al栅（低频各1分） Au栅VFB(Au)VFB(Al)VGC（高频各1分）以区域为单位进行有效组织，通过全国统一商品营销和区域活动促销的方式相结合，紧抓春节黄金时段，及节中、节后的消费需求，以中国古今结合“穿越式”的龙年春节文化为主题，security, profit, maintain stability and promote harmonious development as the main content of the three guarantees theme practice activities and stressing party spirit, to conduct, for example campaign, party and further improvement of the level of work. Staff participating in the honest and clean culture construction seminars, staffs sense of probity and enhanced. Founded by honest inspectors team composed of 12 employees to broaden the channels of supervision. Adhere to establish four good leadership activities, staff satisfaction rate of 98% to the team. -Group work dynamic. Promoting the openness of factory Affairs, proposal for a love letter box, to the vital interests of the staff Trade Union delegation leader meeting of the 26 system to discuss and safeguard their democratic rights. Improve the organizational structure of the mission, the work of strengthening. Organize maintenance labor emulation and health Cup competition, enhance the skills of staff. Organized a variety of cultural activities, physical and mental health care staff, to create a harmonious atmosphere. During the Wenchuan earthquake, donated all the company employees, to love, to support the disaster areas. This year, the company has won the Su . Cutting costs can be controlled, money should not be wasted management philosophy, management analysis, to improve management quality, improve cost control capacity and market competitiveness. Innovation of science and technology-science and technology innovation is to play the role of science and technology as the primary productive force, active use of new technologies, new materials, new processes, new equipment, increase investment in science and technology, strengthening scientific and technological training, speeding up transforming scientific and technological achievements, forming a number of proprietary technology, enhancing core competitiveness. Resource-saving-the-resources saving enterprise was to reduce coal consumption, water consumption, electricity at the core, enhance the operation of lean management to realize low consumption, high efficiency, reduce production costs. Second is to strengthen the business, financial, material, information and the optimization of organization and management, saving the internal transaction costs. Harmonious development of harmonious development-is to construct a foreign environment for development. XING refers to the internal security firm and internal management of the internal management measures are effective, harmonious. Foreign currency means Enterprise coordinating development of homeopathy, well, get along with the neighbors better. (B) XX 2013 five enterprises building intrinsic safety power company goals are: unplanned outage 0 times. Class of disorders 0, 0 is equivalent forced outage rate. No personal injury accident, material and equipment accidents do not occur, no fire, no environmental pollution accident. Enterprise integrated to achieve zero cases of violation, zero accidents, zero. Quality goal is: when generating capacity 7.5第 7 页 共 7页