Solar Frontier K.k.

International Business Machines Corporation

Homare Hiroi

Hiroki Sugimoto

Jeehwan Kim

Oki Gunawan

David Brian Mitzi

Noriyuki Sakai

A photovoltaic device includes an absorber layer having a back contact formed on the absorber layer, the back contact having an exposed surface free from a substrate. It further includes a top contact formed in contact with a transparent conductive layer opposite the back contact and a stressor layer forming a superstrate on the absorber layer opposite the back contact.

Substrate-free thin-film flexible photovoltaic device and fabrication method

A method for thermal exfoliation includes providing a target layer on a substrate to form a structure. A stressor layer is deposited on the target layer. The structure is placed in a temperature controlled environment to induce differential thermal expansion between the target layer and the substrate. The target layer is exfoliated from the substrate when a critical temperature is achieved such that the target layer is separated from the substrate to produce a standalone, thin film device.

A compound-based thin film solar cell which has a high photovoltaic conversion efficiency is obtained. The compound-based thin film solar cell is provided with substrate (), back surface electrode layer () formed on substrate (), p-type light absorption layer () formed on back surface electrode layer (), n-type high resistance buffer layer () formed on p-type light absorption layer (), and ZnO film () formed on n-type high resistance buffer layer (), where n-type high resistance buffer layer () includes a first buffer layer (A) formed on the p-type light absorption layer () and a second buffer layer (B) formed on the first buffer layer (A) and where the second buffer layer (B) is formed by a material which has a lattice constant closer to the lattice constant of the ZnO film () than the first buffer layer (A).

Growing community of inventors

Tokyo, Japan

Homare Hiroi