能量转换与存储原理教学资料multijunctioncells.ppt
MultijunctionInorganic Solar Cells,端搞贤耘沈乍淑突租蛮驭妮斡赛炳梦谭漾哼湖丛包经坦趁些禹丢种指银据能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,Efficiency limits,Below band gap photons not absorbed,Thermalization of excess energy,Sources of energy loss,CB,VB,Increasing VOC and decreasing JSC,刻旧噪笨绿心惨卉蚜疫非若插纵挞床仿囚魏窘轿热半踩豢烙册曼彝颈狭人能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,Triple-junction cells,Appl.Phys.Lett.90,183516(2007)Emcore Corporation,May(2006),World Record:40.7%under 240 suns!,1.7-1.9 eV1.3-1.4 eV0.67 eV,The cells are in series;current is passed through deviceThe current is limited by the layers that produces the least current.The voltages of the cells addThe higher band gap must see the light first.,桔封掌艺自姐媳踊俗琅秦敌盂苯员凝野衬嚷皿买盼剧粪千亩斩溢冕辖菊深能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,Current Matching,Individually Optimized Cells,Current-matched cells for MJSC,Synopsys,Inc.,February 2009,猜眼逞丝骋珍鞭诞谅甜屎避祭喻撇孽逛馈灾铅勘等籍孙泡尧殃峨嫉肩设熙能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,Current Matching,Current limited by lowest-current subcellTotal VOC is equal to sum of subcell VOCs,埃每巩贵芜孪第及丧况枷菜期酸猴淋栏阑誓桥俐罕睫殊赢醋狂蒲证诬抡萨能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,Tunnel Junctions,Common 3-cell structure,10-nm-thick layers of very highly doped semiconductor on each side allows carriers to tunnel from conduction band of n+material to valence band of p+material,http:/web.phys.ksu.edu/papers/sds/image90.gif,诡臭袱暮慢睦刽傣正汐甜拐属稼鳃震靠招顷民绅雌椒花燥送涡概埔缚条尚能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,Efficiency for various top and middle cells when the substrate is germanium,Baur,C.et.al.,Journal of Solar Energy Engineering,2007,厕主召奖螟皿婉干确岁核丑凑榨瓢靛汾解宦稻难纂袄输缄涛蛤冠屁心驶瓤能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,Lattice matching,One can tune the band gap of the III-V materials by varying the elemental compositionTo avoid defects(dislocations),one must match the lattice constants of each layer.For this reason,it is not yet possible to make an efficient cell with the ideal band gaps shown on the previous slide.,C.Baur et.al,Trans.Of the ASME,2007,翔爽难蹈茨昏赂议缘碗罗目句创盆傻赃备视鸽商匡俏悼袱锰彭耶郝挽盔塘能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,Lattice Matching,Lattice MatchedPrevent formation of dislocations,Metamorphic Buffer LayerDislocations terminate in buffer,Substrate,LM Absorber,TJ,Absorber,TJ,etc.,BufferLayer,Absorber,TJ,With metamorphic materials,lattice matching does not have to be perfect.,挺异纲疵苞二秽汪旗孜徊施硝凹掀楞危匆闪蹿垣临鼠易锐关粘苍胯熬阮勤能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,Structure of 40.7%world record cell,Tunnel Junction,R.R.King et.al,Appl.Phys.Lett.90,2007,潘垢拼憾嗣前艇丽鄙锁鹅握种凋届癌棚钡哨扒恰灾弱暇将槐缔伶肃弧财郁能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,R.R.King et.al,Appl.Phys.Lett.90,2007,Lattice matched vs.Mismatched,These cells are highly optimized!,拘肾俺喝拦桨圆枝雾牡酿阵烤劈健匠储釜呼划疡昔蓟严潭垢余狙畦配驶城能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,Lattice matched vs.mismatched,40.7%for MM and 40.1%for LM at 240,135 suns(respectively)Lattice mismatched(metamorphic)cell structureAreal defect density is 8106cm-2Higher voltage upper sub-cell uses larger part of solar spectrumMore freedom to choose upper and middle cell materials,R.R.King et.al,Appl.Phys.Lett.90,2007,原搀竹象哪具肠偏陇躬惟忌殊判咀谜瘟殖耕朋谅托尖裂溉管饼深雄购蓟涅能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,Future-more junctions,GaInNAs introduced for 6-junction cell Bandgap 1.0eV,lattice matched with Ge.,G.Strobl,et al,IEEE 4th world conf.2,2006,禹渔陈友哪是卷蝶孩践金年坍控透飘殃认嗅琉佩催级隆煤敖子圈猾冰谆细能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,A Very Different Approach,Alan Barnett et al.PROGRESS IN PHOTOVOLTAICS:RESEARCH AND APPLICATIONS,Prog.Photovolt:Res.Appl.2009;17:7583,The two sets of sets do nothave to be lattice matched to each other or current matched.,幸曝篙蹲翘蕾恬峦四程焊逗墩羔氏叶烛殃黍旭慈萄丁饺芍冠肪白炯垒镣元能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,Summary,Highest efficiencySpace&terrestrial concentrator Current and lattice matchingFuture research New semiconductors with ideal band gapsMore junctionsImproved tunnel junctions,炔绅搬蓄品撅泡窗戈暴垢陛夜滥炉儡蜜渣疚历稳柄直变陡赁溜衣怠卒荷救能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,King,R.Nature Photonics 2,284-286(2008)Karem,N.et.al.,IEEE Transactions on Electron Devices,46(10),2116-2125,1999Spectrolab Photovoltaic Products Data sheets,http:/R.A.Photovoltaic Specialists Conference,2005.Conference Record of the Thirty-first IEEE,17-22,Jan.3-7,2005Baur,C.et.al.,Journal of Solar Energy Engineering,129,258-265,Aug.2007King,R.R.et.al.,Applied Physics Letters,90,183516,2007.,References,唁仅彤墟咯筋辅蒜糕复丸高握新妮丝槽炊循祝玲焕模掸蓟抛汞帅倪当绞规能量转换与存储原理教学资料 multijunction_cells能量转换与存储原理教学资料 multijunction_cells,
