How can I call particular array value of array in php?

As you mentioned that you don't want to call it as $array[12][1][14][0]['service_desc'] you can use extract function which will create variables from your array,

extract($array[12][1][14][0]);
echo $service_desc;

And then you can use your particular key such as service_desc as variable.

You can try this function: (Please optimize as per your requirements)

$arr ="<YOUR ARRAY>";
$val = "service_desc";
echo removekey($arr, $val);

function removekey($arr, $val) {
    $return = array();
    foreach ($arr as $k => $v) {

        if (is_array($v) && $k !== $val) {

            removekey($v, $val);
            continue;
        }
        if ($k == $val) {

            echo ($arr[$k]);               
            die;
         }
        $return[$k] = $v;
    }
    return $return;
}

You can use array_walk_rescursive to frame a single dimensional array of matching keys:

DEMO

<?php
$array[12][1][14][0]['service_desc']  = 'Avaya Implementation Servic';
$array[12][1][14][0]['service']       = 'dsfasf';
$array[12][1][114][0]['service_desc'] = 'Avaya Implementation Servicasdfdsf';

$searchKey = 'service_desc';

$desiredValues = [];
array_walk_recursive($array, function ($v, $k) use ($searchKey, &$desiredValues) {
    if ($k === $searchKey) {
        $desiredValues[] = $v;
    }
});

print_r($desiredValues);

So this will yield:

Array
(
    [0] => Avaya Implementation Servic
    [1] => Avaya Implementation Servicasdfdsf
)

You might use the array_walk_recursive function.

array_walk_recursive($array, function ($val, $key) {
    if ($key == 'service_desc') print_r($val); 
} );

Instead of the print_r statement, you can collect your data into another structure, which you convey using the use statement, or with the $userdata additional parameter (see http://www.php.net/manual/en/function.array-walk-recursive.php ).

$results = array();
array_walk_recursive($array, function ($val, $key) use (&$results) {
    if ($key == 'service_desc') {
        $results []= $val;
    }
} );

Pay extra care to the & in front of the use (&$results) otherwise your array of results will be considered immutable inside the callback (i.e. all changes discarded).

Convert multidimensional array to single array using iterator_to_array

REF: http://php.net/manual/en/function.iterator-to-array.php

$service_desc= iterator_to_array(new RecursiveIteratorIterator(new RecursiveArrayIterator($your_array)), 0);
print_r($service_desc);

Result:

Array
(
    [name] => Avaya Implementation  Services
    [service_id] => 14
    [ser_type_id] => 1
    [service_desc] =>Avaya Implementation Servic
)