Creating the sub-directories inside the Amazon S3 buckets using script

yes, it should be easy. instead of giving

$s3->putObjectFile($fileTempName, "jurgens-nettuts-tutorial", $fileName, S3::ACL_PUBLIC_READ)

just give

$folderName = 'xyz/abc/filename';  // path on s3 bucket.

$s3->putObjectFile($fileTempName,"jurgens-nettuts-tutorial" ,$folderName ,S3::ACL_PUBLIC_READ );

define the directory in foldername

CodeHunter