When I try this:

$worksheet1->write(0,1,"Modules", $format);
$worksheet1->write(0,2,"Excel");
$worksheet1->write(0,3, "Dumper");
[download]

It gives me this:

Modules    Excel    Dumper
[download]

and when I do this (which is your code)

$worksheet1->write(0,1,"Modules", $format);
$worksheet1->write(1,1,"Excel");
$worksheet1->write(2,1, "Dumper");
[download]

I get this:

Modules
Excel
Dumper
[download]

I think you just need to watch which index is for row and which is for column.

(EDITED because I misread and got backward what was desired vs. what you were getting)

Another EDIT:
and if I do this:

$worksheet1->write(0,0,"A1");
$worksheet1->write(0,1,"B1");
$worksheet1->write(0,2, "C1");

$worksheet1->write(1,0,"A2");
$worksheet1->write(1,1,"B2");
$worksheet1->write(1,2, "C2");

$worksheet1->write(2,0,"A3");
$worksheet1->write(2,1,"B3");
$worksheet1->write(2,2, "C3");
[download]

I get:

A1    B1    C1
A2    B2    C2
A3    B3    C3
[download]

Where each of the contents is also the name of the cell. Normally you'd do something like that with a nested loop