Impact of scaling base thickness on the performance of heterojunction phototransistors

Optimum dimensions of circular fins of trapezoidal profile with variable thermal conductivity and heat transfer coefficients are obtained. Linear variation of the thermal conductivity is considered of the form k = k0(1 + εT/T0), and the heat transfer coefficient is assumed to vary according to a power law with distance from the bore, expressed as h = K[(r − r0)/(r0 − re)]m. The results for m = 0, 0.8, 2.0, and −0.4 ≤ ε ≤ 0.4, have been expressed by suitable nondimensional parameters which are presented graphically. It is shown that considering the thermal conductivity as constant, the optimum base thickness and volume of the fin are inversely proportional to the thermal conductivity of the material of the fin, while the optimum length and effectiveness are independent of the properties of the material used.

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The Effect of Base Thickness on Photoconversion Efficiency in Textured Silicon-Based Solar Cells

Technical Physics Letters ◽

10.1134/s1063785018100139 ◽

2018 ◽

Vol 44 (10) ◽

pp. 873-876 ◽

Cited By ~ 3

Author(s):

A. V. Sachenko ◽

V. P. Kostylyov ◽

A. V. Bobyl ◽

V. N. Vlasyuk ◽

I. O. Sokolovskyi ◽

...

Keyword(s):

Solar Cells ◽

Photoconversion Efficiency ◽

Base Thickness ◽

Silicon Based

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Application de la méthode photonique à la détermination des paramètres physiques d'une cellule solaire monocristalline

Canadian Journal of Physics ◽

10.1139/p02-002 ◽

2002 ◽

Vol 80 (7) ◽

pp. 733-743 ◽

Cited By ~ 1

Author(s):

M Ben Amar ◽

A Ben Arab

Keyword(s):

Solar Cell ◽

Silicon Solar Cell ◽

Diffusion Length ◽

Optical Absorption Coefficient ◽

Physical Parameters ◽

Base Region ◽

Technological Parameters ◽

Base Thickness ◽

Modulated Light ◽

Minority Carriers

The photonic's method is used in the study of monocristalline silicon solar cell (N+P). The induced photocurrent in the cell is analyzed with respect to the technological parameters such as the optical absorption coefficient of silicon and the emitter and base thickness. The spatial and frequential variations of the photocurrent of the cell, when the latter is illuminated by a sinusoidal modulated light, allow access to the diffusion length and lifetime of the minority carriers generated in a given region of the cell. In this paper, the physical parameters related to the base region are determined. In addition, this access is shown to be possible only when the total photocurrent of the cell is reduced to the base diffusion photocurrent.

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Bipolar SiC-Diodes – Challenges Arising from Physical and Technological Aspects

Materials Science Forum ◽

10.4028/www.scientific.net/msf.556-557.889 ◽

2007 ◽

Vol 556-557 ◽

pp. 889-894 ◽

Cited By ~ 6

Author(s):

Wolfgang Bartsch ◽

Heinz Mitlehner ◽

S. Gediga

Keyword(s):

High Voltage ◽

Basal Plane ◽

Current Level ◽

Experimental Results ◽

Junction Temperature ◽

Base Thickness ◽

Switching Behaviour ◽

A Current

In this contribution we summarize measurements on bipolar high voltage SiC-diodes which were fabricated on 4H-SiC wafers preferentially cut 4° off the [0001] basal plane, whereas the p-emitter thickness was varied in predetermined ratios to the n-base thickness. The switching behaviour of optimized 6.5 kV-Diodes at a current level of 25 A is shown at DC link voltages up to 4 kV and at a junction temperature of 125°C. Experimental results are discussed in terms of snappiness.

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Base thickness determination from the punch-through voltage for vertical n-p-n transistors incorporated into I2L elements

Technical Physics ◽

10.1134/1.1648969 ◽

2004 ◽

Vol 49 (2) ◽

pp. 269-271

Author(s):

S. V. Shutov ◽

A. N. Frolov ◽

V. N. Litvinenko ◽

A. A. Frolov

Keyword(s):

Base Thickness ◽

Thickness Determination

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Morphologic variation in the USDA/ARS rhubarb germplasm collection

Plant Genetic Resources ◽

10.1017/s1479262109990116 ◽

2009 ◽

Vol 8 (1) ◽

pp. 35-41 ◽

Cited By ~ 4

Author(s):

Alberto Pantoja ◽

Joseph C. Kuhl

Keyword(s):

Germplasm Collection ◽

Morphological Characters ◽

Morphological Data ◽

Skin Colour ◽

Base Thickness ◽

Flesh Colour ◽

Combining Data ◽

Wide Range ◽

Morphologic Variation ◽

The Mean

Rhubarb includes approximately 60 species in the genusRheum. It has been utilized for thousands of years for medicinal purposes, but only recently identified for its culinary use. In the mid 1700s, edible petioles were discovered on seedlings from rhubarb species. Hundreds of cultivars have since been identified for a wide range of uses from tarts to wine. Unfortunately, propagation by seed and irregular naming has resulted in a plethora of similarly named cultivars and multitude of phenotypes. Fifteen morphological characters were evaluated to differentiate rhubarb cultivars in the USDA, ARSRheumcollection in Palmer, Alaska. Two years of morphological data, focusing on horticultural characteristics indicated variation between the years. To improve cultivar resolution, the results suggest using 1 year's data instead of combining data from different years. The mean °Brix observed was 3.8, with a range from 2.2 to 6.1. Flesh colour and basal skin colour were poorly correlated (R2 = 0.462); overall skin colour was more red at the base than in the middle of the petiole. Rhubarb character categories, in particular petiole number and petiole base thickness, need to be modified to better anticipate the range of expected values, and thereby contribute improved reproducibility and reliability to separate cultivars based on morphological characters.

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