微电子专业英语
上QQ阅读APP看本书，新人免费读10天
设备和账号都新为新人
上一章目录下一章

7.3 Energy Bands for a pn Junction

The electron-energy diagram conveys a great deal of information about a semiconductor device，and it is well worthwhile learning how to construct these diagrams. It is not a good idea to try to memorize the diagram for every device-the simple stages of construction are what must be mastered. 7. It is not a good idea to try to memorize the diagram for every device-the simple stages of construction are what must be mastered. 提示：memorize含有“死记”的意思；what must be mastered是名词从句作表语。

（1）Start by putting the Fermi level on paper for one of the layers of semiconductor-any one will do. 8. Start by putting the Fermi level on paper for one of the layers of semiconductor-any one will do. 提示：any one will do表示任何人都能做。因为对于突变结，同一个区域中费米能级为常数，绘制时只要绘制一条水平线，而且开始时对这条水平线位置没有制约，因此对于只要绘一条水平线的要求“任何人都能做”。

（2）Build the band round this Fermi level. The conduction band is close to the Fermi level for n-type material，but the valence band is close in p-type material. 9. The conduction band is close to the Fermi level for n-type material，but the valence band is close in p-type material. 提示：按照含义，第二个close的后面应该有to the Fermi level，因为前面已经出现过，而且结构相同，因此可以省略。

（3）Draw the other Fermi levels at the right height on the diagram，allowing for applied voltages. The more positive of two layers is nearer the bottom of the page. 10. Draw the other Fermi levels at the right height on the diagram，allowing for applied voltages. The more positive of two layers is nearer the bottom of the page. 提示：at the right height表示“正确的高度”；allowing for applied voltages进一步解释说明要根据外加电压确定正确的高度，因为按照物理含义，两个区域之间费米能级之差就等于外加电压乘以电子电荷；后一句是比较级，进一步说明两个费米能级之间谁的位置更高；page指绘制能带图的页面，翻译时可以直接翻成图的底部。

（4）Complete these bands，keeping the gap between conduction and valence bands constant.

（5）Join up the conduction band from each layer to the next，using S-shaped double curves，and do the same for the valence band. 11. Join up the conduction band from each layer to the next，using S-shaped double curves，and do the same for the valence band. 提示：由图7.3可见，不管是什么偏置状态，p区和n区界面附近能带图的导带底之间呈现S形，句子用using S-shaped double curves一方面点明了S形，而且更加形象地说明S形包括了两个方向转弯，即其中的curve表示转弯，double curves表示“双弯”，不能翻译为双曲线，也不能翻译为两条曲线。

（6）Fill in details such as free carriers，doping ions，and applied voltages. Remember that doping ions are present in depletion layers，but that large numbers of free carriers are not. 12. Remember that doping ions are present in depletion layers，but that large numbers of free carriers are not. 提示：注意本句中Remember与第7句中memorize含义的区别。Remember是记住，memorize带有“死记”的意思；这是祈使句，带有两个宾语从句，这两个宾语从句用but连接，表示转折。

A pn junction and its associated energy band is shown in Fig.7.3.

上一章目录下一章