1 INTRODUCTION

2 HST/WFC3 OBSERVATIONS  
2.1 Sample Selection  
2.2 Observing Strategy  
2.3 Data Reduction  
2.4 Source Detection and Photometry  
2.5 Artificial Star Tests  

3 DATA ANALYSES OF THE BROWN DWARF PRIMARIES  
3.1 Photometric Properties  
3.2 Primary Masses  

4 DATA ANALYSES FOR MULTIPLICITY  
4.1 Search for Companions  
4.2 Survey Completeness  
4.3 Constraints on Binary Frequency  

5 DISCUSSION

6 CONCLUSIONS