Work function and induced band bending characterization for engineering of selective contact for solar cells

Marshall Wilson1*, Alexandre Savtchouk1, Ziv Hameiri2, Jie Cui3 and Jacek Lagowski1

1Semilab SDI, Tampa, FL 33617, USA

2University of New South Wales (UNSW), Sydney NSW 2052, Australia

3Australian National University (ANU), Canberra ACT 0200, Australia

Adv. Mater. Lett., 2018, 9 (9), pp 629-631

DOI: 10.5185/amlett.2018.2084

Publication Date (Web): Jun 14, 2018



This work demonstrates the effectiveness of non-contact Kelvin-probe and surface photovoltage characterization of the work function (WF) induced barriers formed in silicon (Si) by thin 5nm carrier selective contact films of MoOx, TiO2 and MgF2.  The calibrated Kelvin probe in the dark and under strong illumination where used to determine the dark WF of the deposited films and the band bending in the Si, FBB = WFDark – WFLight.  The ac-surface photo voltage provided an independent measurement of the Si depletion layer width.  Whole wafer mapping of all parameters can be performed.  For n-type Si the high work function oxides MoOx (WF~5.7eV) and TiO2 (WF~5.0eV) are found to induce a depletion barrier with the height increasing with WF as FBB[eV] = 0.23WF – 0.77, i.e. quite similar to the well-known relationship for metal-silicon contacts.  For the low work function MgF2 film, a depletion barrier was induced only in p-type Si.  For this case, full wafer mapping revealed a lower WF pattern coinciding with larger band bending giving the slope, DFBB/DWF ~ -0.52.  The slopes of 0.23 and 0.52 for n- and p-type Si deviates significantly from the ideal slope of 1.  This result implies that the barrier formation at the Film-Si heterojunction is limited by the effect of interfacial layers and interface states in analogy to the well-known effects in Metal-Si contacts. It is believed that this demonstrated very fast, preparation-free, non-contact characterization technique can benefit research and engineering of selective contacts for solar cells. 


Solar cell, work function, band bending, hole selective contacts, electron selective contacts.

Previous issues

Celebrating 10th Years of Diamond Open Access Publishing in Advanced Materials  

Cerebral Oxygenation Studies Through Near Infrared Spectroscopy: A Review

Analysis of Fine Sulfoaluminate Cement by Strength and Thermogravimetric Analysis

Characterization of the Interfacial Surface Energy for Composite Electrical Conduction Measurements using Two Full Range Percolation Threshold Models

Quantitative Detect of Fatigue of Membrane of Erythrocyte in Uniform Shear Field

Ecofriendly-developed Polyacrylic Acid-coated Magnetic Nanoparticles as Catalysts in Photo-fenton Processes

Evaluation of Drug Interactions with Medications Prescribed to Ambulatory Patients with Metabolic Syndrome in Urban Area

Fiber-reinforced Cementitious Composite: Sensitivity Analysis and Parameter Identification 

Evaluation of Drug Utilization Patterns Based on World Health Organization Drug use Indicators at Outpatients Clinics

Are Quantitatively Micro-machined Scaffolds Effective for Cell Technology?

Synthesis and Characterization of Gold Nanoparticles from Lobelia Nicotianifolia Leaf Extract and its Biological Activities

Advanced Oxidations of Tartrazine Azo-dye

Antifungal Activity of Salvia jordanii Against the Oral Thrush Caused by the Cosmopolitan Yeast Candida albicans among Elderly Diabetic Type 2 patients

Upcoming Congress

Knowledge Experience at Sea TM