<div dir="ltr">

<span style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:small;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline">I wanted to add that I used RF Sputtering at room temperature from a ZnO target with 99.99% purity and Ar:O2 flow with the ratio of 2:1, if you can provide any suggestions for improving the film quality that would be great. </span><br><div><span style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:small;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline"><br></span></div><div><span style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:small;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline">Thanks again and wish you all a great day!</span></div></div><div class="gmail_extra"><br clear="all"><div><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><a href="https://scholar.google.com/citations?hl=en&user=-5mNcfYAAAAJ&view_op=list_works&sortby=pubdate" target="_blank">Mohamed T. Ghoneim</a>, <div>Postdoctoral Researcher</div><div><span style="font-size:12.8px">MIT </span>Media Lab, Building E-15, Fourth Floor, Room 443g.</div><div><span style="font-size:12.8px"><a href="https://sites.google.com/view/mtghoneim" target="_blank">Website<br></a></span><br></div></div></div></div></div></div></div></div></div></div></div></div>
<br><div class="gmail_quote">On Mon, Jan 29, 2018 at 10:31 AM, Mohamed Ghoneim <span dir="ltr"><<a href="mailto:mohamed.t.ghoneim@gmail.com" target="_blank">mohamed.t.ghoneim@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Dear All,<div><br></div><div>

<div class="m_2150571426652343148gmail-nova-e-text m_2150571426652343148gmail-nova-e-text--size-m m_2150571426652343148gmail-nova-e-text--family-sans-serif m_2150571426652343148gmail-nova-e-text--spacing-s m_2150571426652343148gmail-nova-e-text--color-inherit m_2150571426652343148gmail-redraft-text" style="border:0px;text-transform:none;display:block;margin:0px 0px 15px;padding:0px;color:rgb(17,17,17);font-weight:400;font-family:Roboto,Arial,sans-serif;font-size:0.875rem;line-height:1.3;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;letter-spacing:normal;text-align:left;text-indent:0px;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial"><span style="font-size:0.875rem">I am sputtering ZnO thin films for pH sensing. Getting repeatable and stable results is a challenge that I though first has to do with chemical fouling and other selectivity issues but based on the literature these issues are there for ZnO but usually do not affect the reliability of measurements to a great extent. I am more concerned now about the crystallinity and stoichiometry effects and as well as surface cleaning techniques to make sure I do not have contaminants on the surface that significantly affects the surface chemistry.</span></div><div class="m_2150571426652343148gmail-nova-e-text m_2150571426652343148gmail-nova-e-text--size-m m_2150571426652343148gmail-nova-e-text--family-sans-serif m_2150571426652343148gmail-nova-e-text--spacing-s m_2150571426652343148gmail-nova-e-text--color-inherit m_2150571426652343148gmail-redraft-text" style="border:0px;text-transform:none;display:block;margin:0px 0px 15px;padding:0px;color:rgb(17,17,17);font-weight:400;font-family:Roboto,Arial,sans-serif;font-size:0.875rem;line-height:1.3;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;letter-spacing:normal;text-align:left;text-indent:0px;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial"><span style="font-size:0.875rem">These are the XRD results of the films (x-axis is 2Theta and the blue (XYZ) are for ZnO:</span></div><div class="m_2150571426652343148gmail-nova-e-text m_2150571426652343148gmail-nova-e-text--size-m m_2150571426652343148gmail-nova-e-text--family-sans-serif m_2150571426652343148gmail-nova-e-text--spacing-s m_2150571426652343148gmail-nova-e-text--color-inherit m_2150571426652343148gmail-redraft-text" style="border:0px;text-transform:none;display:block;margin:0px 0px 15px;padding:0px;color:rgb(17,17,17);font-weight:400;font-family:Roboto,Arial,sans-serif;font-size:0.875rem;line-height:1.3;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;letter-spacing:normal;text-align:left;text-indent:0px;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial"><span style="font-size:0.875rem"><img src="cid:ii_16142869a2a06d01" alt="Inline image 1" width="544" height="248" style="margin-right:0px"><br></span></div><div class="m_2150571426652343148gmail-nova-e-text m_2150571426652343148gmail-nova-e-text--size-m m_2150571426652343148gmail-nova-e-text--family-sans-serif m_2150571426652343148gmail-nova-e-text--spacing-s m_2150571426652343148gmail-nova-e-text--color-inherit m_2150571426652343148gmail-redraft-text" style="border:0px;text-transform:none;display:block;margin:0px 0px 15px;padding:0px;color:rgb(17,17,17);font-weight:400;font-family:Roboto,Arial,sans-serif;font-size:0.875rem;line-height:1.3;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;letter-spacing:normal;text-align:left;text-indent:0px;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial"><span style="font-size:0.875rem">

<span style="color:rgb(17,17,17);font-family:Roboto,Arial,sans-serif;font-size:14px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:left;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline"></span></span></div>

<div class="m_2150571426652343148gmail-nova-e-text m_2150571426652343148gmail-nova-e-text--size-m m_2150571426652343148gmail-nova-e-text--family-sans-serif m_2150571426652343148gmail-nova-e-text--spacing-s m_2150571426652343148gmail-nova-e-text--color-inherit m_2150571426652343148gmail-redraft-text" style="font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;text-decoration-style:initial;text-decoration-color:initial;border:0px;display:block;margin:0px 0px 15px;padding:0px;color:rgb(17,17,17);font-family:Roboto,Arial,sans-serif;font-size:0.875rem;line-height:1.3;text-align:left;background-color:rgb(255,255,255)"><span style="font-size:0.875rem">These are the XPS results of the films (the blue one is the as-deposited ZnO and the red one is after some tests in buffer solutions):</span></div><img src="cid:ii_16142889bf09c344" alt="Inline image 2" width="544" height="332"><br class="m_2150571426652343148gmail-Apple-interchange-newline">

<div class="m_2150571426652343148gmail-nova-e-text m_2150571426652343148gmail-nova-e-text--size-m m_2150571426652343148gmail-nova-e-text--family-sans-serif m_2150571426652343148gmail-nova-e-text--spacing-s m_2150571426652343148gmail-nova-e-text--color-inherit m_2150571426652343148gmail-redraft-text" style="border:0px;text-transform:none;display:block;margin:0px 0px 15px;padding:0px;color:rgb(17,17,17);font-weight:400;font-family:Roboto,Arial,sans-serif;font-size:0.875rem;line-height:1.3;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;letter-spacing:normal;text-align:left;text-indent:0px;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial"><span style="font-size:0.875rem"><br></span></div><div class="m_2150571426652343148gmail-nova-e-text m_2150571426652343148gmail-nova-e-text--size-m m_2150571426652343148gmail-nova-e-text--family-sans-serif m_2150571426652343148gmail-nova-e-text--spacing-s m_2150571426652343148gmail-nova-e-text--color-inherit m_2150571426652343148gmail-redraft-text" style="border:0px;text-transform:none;display:block;margin:0px 0px 15px;padding:0px;color:rgb(17,17,17);font-weight:400;font-family:Roboto,Arial,sans-serif;font-size:0.875rem;line-height:1.3;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;letter-spacing:normal;text-align:left;text-indent:0px;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial"><span style="font-size:0.875rem">Can you please share thoughts about the effect of (a) Crystalline Structure and (b) Stoichiometry (or elemental composition) of ZnO thin film on its pH sensing capabilities and how it affects the surface integrity in terms of: </span><span style="font-size:0.875rem">1- Sensitivity </span><span style="font-size:0.875rem">2- Repeatability </span><span style="font-size:0.875rem">3- Stability </span><span style="font-size:0.875rem">of the Measurments.</span></div><div class="m_2150571426652343148gmail-nova-e-text m_2150571426652343148gmail-nova-e-text--size-m m_2150571426652343148gmail-nova-e-text--family-sans-serif m_2150571426652343148gmail-nova-e-text--spacing-s m_2150571426652343148gmail-nova-e-text--color-inherit m_2150571426652343148gmail-redraft-text" style="border:0px;text-transform:none;display:block;margin:0px 0px 15px;padding:0px;color:rgb(17,17,17);font-weight:400;font-family:Roboto,Arial,sans-serif;font-size:0.875rem;line-height:1.3;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;letter-spacing:normal;text-align:left;text-indent:0px;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial">All thoughts, comments are highly appreciated,</div><div class="m_2150571426652343148gmail-nova-e-text m_2150571426652343148gmail-nova-e-text--size-m m_2150571426652343148gmail-nova-e-text--family-sans-serif m_2150571426652343148gmail-nova-e-text--spacing-s m_2150571426652343148gmail-nova-e-text--color-inherit m_2150571426652343148gmail-redraft-text" style="border:0px;text-transform:none;display:block;margin:0px 0px 15px;padding:0px;color:rgb(17,17,17);font-weight:400;font-family:Roboto,Arial,sans-serif;font-size:0.875rem;line-height:1.3;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;letter-spacing:normal;text-align:left;text-indent:0px;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial"></div><div class="m_2150571426652343148gmail-nova-e-text m_2150571426652343148gmail-nova-e-text--size-m m_2150571426652343148gmail-nova-e-text--family-sans-serif m_2150571426652343148gmail-nova-e-text--spacing-s m_2150571426652343148gmail-nova-e-text--color-inherit m_2150571426652343148gmail-redraft-text" style="border:0px;text-transform:none;display:block;margin:0px;padding:0px;color:rgb(17,17,17);font-weight:400;font-family:Roboto,Arial,sans-serif;font-size:0.875rem;line-height:1.3;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;letter-spacing:normal;text-align:left;text-indent:0px;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial">Thanks in advance and wish you a great day!</div>

</div><div><br></div><div><br clear="all"><div><div class="m_2150571426652343148gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><a href="https://scholar.google.com/citations?hl=en&user=-5mNcfYAAAAJ&view_op=list_works&sortby=pubdate" target="_blank">Mohamed T. Ghoneim</a>, <div>Postdoctoral Researcher</div><div><span style="font-size:12.8px">MIT </span>Media Lab, Building E-15, Fourth Floor, Room 443g.</div><div><span style="font-size:12.8px"><a href="https://sites.google.com/view/mtghoneim" target="_blank">Website<br></a></span><br></div></div></div></div></div></div></div></div></div></div></div></div>
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