Download Solar Cells by Harold J. Hovel (Eds.) PDF

Posted by

By Harold J. Hovel (Eds.)

Show description

Read or Download Solar Cells PDF

Best construction books

Crossing boundaries, building bridges: comparing the history of women engineers, 1870s-1990s

Ladies engineers were within the public limelight for many years, but we have now unusually little traditionally grounded knowing of the styles of employment and schooling of girls during this box. so much experiences are both coverage papers or restricted to statistical analyses. in addition, the scant ancient learn up to now to be had emphasizes the person, unmarried and certain personality of these ladies operating in engineering, usually utilizing anecdotal proof yet ignoring greater matters just like the styles of the labour industry and academic associations.

The Construction of Cognitive Maps

And approaches that are unique to people of their encoding, storing, interpreting and retrieving spatial wisdom for varied initiatives. The authors current and talk about connectionist types of cognitive maps that are according to neighborhood illustration, as opposed to versions that are in response to disbursed illustration, in addition to connectionist versions touching on language and spatial kinfolk.

Architect's Handbook of Construction Detailing, Second Edition

Considerably up to date with revisions to almost all 200-plus information, this moment variation of Architect's instruction manual of development Detailing presents architects, engineers, inside designers, contractors, and different construction pros with all the universal development info, fabrics info, and detailing thoughts used through the undefined.

Additional resources for Solar Cells

Example text

CONSTANT ELECTRIC FIELDS Losses due t o s u r f a c e and bulk recombination can be reduced by decreasing t h e j u n c t i o n depth and s u r f a c e recombination v e l o c i t y and by i n c r e a s i n g t h e minority carrier d i f f u s i o n l e n g t h , p a r t i c u l a r l y i n t h e base. Another way t h a t l o s s e s can be reduced is t o provide electric f i e l d s i n one o r both regions of t h e c e l l t o aid i n moving photogenerated carriers toward t h e junction. ( I n t h e o r y , d i f f u s i o n processes provide electric f i e l d s a u t o m a t i c a l l y by e s t a b l i s h i n g concent r a t i o n g r a d i e n t s of donors o r a c c e p t o r s .

Device parameters of Table 5 . of t h e junction much more important than i n s i l i c o n , and t h e base of t h e c e l l correspondingly less important. High values of f r o n t s u r f a c e recombination v e l o c i t y and low values of l i f e t i m e and d i f f u s i o n length i n t h e t o p region cause a s t r o n g decrease i n t h e s p e c t r a l response with i n c r e a s i n g photon energy as c a r r i e r s are generated c l o s e r and c l o s e r t o t h e surface. These high s u r f a c e l o s s e s can be p a r t l y overcome by making t h e junction depth small, a s i n S i cells, o r by e s t a b l i s h i n g an a i d i n g electric f i e l d a t t h e surface.

I n t h e t h i r d model, t h e base is divided i n t o two s e c t i o n s w i t h d i s t i n c t l y d i f f e r e n t p r o p e r t i e s . This a p p l i e s , f o r example, t o t h e "back surface f i e l d " c e l l [5] where a p+ region i s d i f fused i n t o t h e back of t h e p-type base t o enhance both t h e s h o r t c i r c u i t current and open c i r c u i t voltage of t h e c e l l . B. PHOTOCURRENT DERIVATION FOR MONOCHROMATIC LIGHT 17 I n t h o s e i n s t a n c e s where a ”dead l a y e r ” i s believed t o e x i s t a d j a c e n t t o t h e s u r f a c e of t h e device due t o stress introduced by t h e junction d i f f u s i o n , t h e n-type d i f f u s e d t o p region of t h e c e l l can a l s o be divided i n t o two s e c t i o n s with d i f f e r e n t l i f e t i m e s and m o b i l i t i e s .

Download PDF sample

Rated 4.62 of 5 – based on 4 votes