The solar panel on the calculator can capture solar energy and convert it into electrical energy, and the LCD of the calculator supplies power. (Because the display on the calculator is small and requires less power, the size, power, voltage and current of the solar panel are generally smaller than those of the solar panel on the market that we have seen.) The material of the solar panel is amorphous silicon. Silicon is a fairly common element on Earth — sand on beaches, for example, is made of silicon compounds. However, it is difficult to purify silicon, which is why it is not cheap, even though it is so abundant in the earth’s crust.
The silicon in the solar panel of the calculator is not pure because it is doped or chemically treated to add specific impurities. Doped silicon with extra electrons is called N-type, while doped silicon without electrons is called P-type. N-type silicon usually contains added antimony, arsenic or phosphorus, while P-type silicon usually contains added boron, aluminum or gallium. When silicon is treated with phosphine gas or PH3, phosphorus can be added to make N-type silicon, while diborane gas or B2H6 can add boron to make P-type silicon. Generally, the main raw materials used are monosilane (SiH4), disilane (Si2H6), silicon tetrafluoride (SiF4), etc. The purity requirements are very high.
It is also because of the environment in which the calculator is used that the type of solar panel it uses is determined. As we all know, crystalline silicon solar panels can generate electricity only in the sun, while calculators are used indoors with insufficient light. Amorphous silicon solar panels just meet this feature, with good weak light, and can even generate electricity when there is light. Of course, there must be some disadvantages. Its power generation efficiency is relatively low, perhaps even only about 10%, and its service life is relatively short. Calculator As mentioned above, the required current is very small, and amorphous silicon is fully able to meet.
If you want to know more about solar panels, please contact us, the solar panel manufacturer – Huanqi Technology (Shenzhen) Co., Ltd.