Can someone help me find a function F(x,y) that looks like this? (Picture attached)

[pale geyser]

[solved] Any estimated or close enough function works for me
I guess you could say, the curves are exponential in z sub x, or z sub y

[idle hemlock]

,tikz[scale=5]
\draw[->] (-.2,0) -- (1.2,0) node[pos=1.1] {$x$};
\draw[->] (0,-.2) -- (0,1.2) node[pos=1.1] {$y$};
\coordinate[label=below left:$0$] (O) at (0,0);
\coordinate[label=below:$1$] (E) at (1,0);
\coordinate[label=left:$1$] (N) at (0,1);
\foreach \s in {.25,.5,...,4}
\draw plot[domain=0:1, samples=51] (\x,\x^\s);

[slow coyote]

vin100

[idle hemlock]

graph of $\vfunc{f_s}{[0,1]}{[0,1]}{x}{x^s}$ for $s \in \qty{.25,.5,\dots,4}$

[slow coyote]

vin100

[idle hemlock]

flip it horizontally

,tikz[scale=5]
\draw[->] (-.2,0) -- (1.2,0) node[pos=1.1] {$x$};
\draw[->] (0,-.2) -- (0,1.2) node[pos=1.1] {$y$};
\coordinate[label=below left:$0$] (O) at (0,0);
\coordinate[label=below:$1$] (E) at (1,0);
\coordinate[label=left:$1$] (N) at (0,1);
\foreach \s in {.25,.5,...,4}
\draw plot[domain=0:1, samples=51] (\x,{(1-\x)^\s});

[slow coyote]

vin100

vin100

[idle hemlock]

turn it into 3d graph

$\vfunc{h_s}{[0,1]^2}{[0,1]}{(x,y)}{(1-x-y)^s}$ for $s \in \qty{.25,.5,\dots,4}$

[slow coyote]

vin100

[pale geyser]

Someone found the answer: