<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto">In a stepper I would say run a focus expose matrix. In your case start by changing the dose. In the image it looked like you had not reveled the Si. So a higher dose would be a start. But I do not know your resist. <div><br></div><div>In general, it will be hard to make sub micron line space features with your contact aligner. Can you access a stepper? <br><br><div id="AppleMailSignature" dir="ltr">Thanks,<div><br></div><div>Rob </div><div><br></div><div>Sent from my iDidntspellcheckit</div></div><div dir="ltr"><br>On Dec 17, 2020, at 11:07 AM, Sa'ad H <<a href="mailto:saad_m_hassan@hotmail.com">saad_m_hassan@hotmail.com</a>> wrote:<br><br></div><blockquote type="cite"><div dir="ltr">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<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><image.png><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>
</div></blockquote><blockquote type="cite"><div dir="ltr"><span>_______________________________________________</span><br><span>labnetwork mailing list</span><br><span><a href="mailto:labnetwork@mtl.mit.edu">labnetwork@mtl.mit.edu</a></span><br><span><a href="https://mtl.mit.edu/mailman/listinfo.cgi/labnetwork">https://mtl.mit.edu/mailman/listinfo.cgi/labnetwork</a></span><br></div></blockquote></div></body></html>