<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style>
</head>
<body dir="ltr">
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Good Morning Everyone,</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
I trust everyone is well. I have been working on defining lithographic features that are lines separated by trenches both of which are 800nm wide.
<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
I am getting adequate resolution, i.e, the lines are very close to spec. But the sidewalls slope significantly as can be seen in the attached picture.</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
My wafer is fabricated as follows:</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<ol>
<li> Bare Silicon Wafer</li><li>HMDS</li><li>Backside Antireflective Coating (XHiRC-16)</li><li>SPR-955 - 6000 rpm spin - PR thickness - 800nm</li><li>Bake 90 Celsius for 90 seconds<br>
</li><li>Exposure - 125 mJ/cm2 in a contact aligner</li><li>Development 1 minute with ultrasonic</li></ol>
<div><br>
</div>
<div><br>
</div>
<div><br>
</div>
<div><img size="175793" contenttype="image/png" style="max-width: 100%; user-select: none;" unselectable="on" tabindex="-1" data-outlook-trace="F:1|T:1" src="cid:f7fd4dca-63e7-4b8e-a0d8-a8e0e7b58cd5"><br>
</div>
<div><br>
</div>
<div><br>
</div>
<div>Does anyone know how I can achieve nice vertical sidewalls? <br>
</div>
<div><br>
</div>
<div><br>
</div>
<div>Cheers,</div>
<div>Sa'ad<br>
</div>
</div>
</body>
</html>