Add popup on clicking custom button in product edit page in admin in magento 2.3

Question

I have added a custom button in product edit page using product_form.xml like below :

app/code/Company/Module/view/adminhtml/ui_component/product_form.xml

<?xml version="1.0" encoding="UTF-8"?>

<form xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Ui:etc/ui_configuration.xsd">
    <argument name="data" xsi:type="array">
        <item name="buttons" xsi:type="array">
            <item name="set-to-sold" xsi:type="string">Company\Module\Block\Adminhtml\Product\Edit\Button\SoldButton</item>
        </item>
    </argument>
</form>

app/code/Company/Module/Block/Adminhtml/Product/Edit/Button/SoldButton.php

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
namespace Brainvire\ProductType\Block\Adminhtml\Product\Edit\Button;

use Magento\Catalog\Block\Adminhtml\Product\Edit\Button\Generic;

class SoldButton extends Generic
{

    /**
     * @return array
     */
    public function getButtonData()
    {
    return [
        'label' => __('Diamond is SOLD'),
        'disabled' => true,
        'on_click' => sprintf("location.href = '%s';", $this->getUrl('producttype/product/sold')),                
        'class' => 'save primary',
        'sort_order' => 5,
    ]; 

    }
}

the button is added like below :

This is working perfectly. A button is added, and a confirm box is also displayed on button click. But now i want to add a popup and call custom phtml in that popup on button click.

Any ideas how to proceed. Thanks in advance.