JavaScript - Create checkbox using JS

I have to generate checkboxes within a table programatically.

This is what I have until now..

//create a row
var row = document.createElement('tr');
 row.className = 'gridrow';

//create td element
td = document.createElement('td');
td.className = 'gridcell';
td.style.fontWeight = 'normal';
td.rowSpan = 1; 
td.style.width = '80px';

//create checkbox in that td element
var chkbox = document.createElement('checkbox');   
chkbox.id = 'chk' + tbodyNewRowNumber;
chkbox.name = 'chk' + tbodyNewRowNumber;  

//add checkbox to td element
td.appendChild(chkbox);

//add td element to row
row.appendChild(td);   

However, no checkbox shows up :(

What am I missing here?

Try this:

//create checkbox in that td element
var chkbox = document.createElement('input');   
chkbox.type = "checkbox";

chkbox.id = 'chk' + tbodyNewRowNumber;
chkbox.name = 'chk' + tbodyNewRowNumber;  

Thx Ron. Your tip worked out perfectly.