Muhammad,

I know of none.

The best answers will depend on your budget, timescale, and familiarity with microcontrollers and electronics.

Answers can be:

* Use a programmable thermal controller (expensive, large)

* Use an Arduino to control a heating plate, reading a thermistor

How soon do you need this?

I'm not sure about hot plates but you could buy double walled glass cell with inlet and outlet in between inner and outer wall so you can flow a liquid withspecific temperature and control the temperature of the reaction. The liquid would be flown and controlled by a bath circulator. Not the cheapest but possibly the most accurate, I think.

James Garry , could you tell me , a specific model of programmable thermal controller. i want to buy it. we want to to use it for single crystal growth with hot plate.

Sajjad,

A great many devices exist.

I have personally used:

https://www.west-cs.com/products/models/9900-single-loop-controller/

and e5CNs

https://az.rsdelivers.com/product/omron/e5cn-q2hbt-ac100-240/omron-e5cn-pid-temperature-controller-48-x-48-1/7949416

Eurotherm, Watlow, and many other firms make near-identical devices. They all will use PID algorithms to drive cooling or warming elements to some set temperature. They (generally) will read thermocouples (J,K,T, etc.), NTCs, platinum thermometers (Pt100, Pt1000), silicon diodes, etc.

If you are brave (!), AliExpress and DHGate have near-identical clones - but they may lack warranties, accuracy, and some features. I have bought chinese clones for non-critical applications, and they have worked as well as 'branded' items.

https://www.dhgate.com/product/digital-led-pid-temperature-controller-thermal/408879526.html