Electroluminescent display with space charge removal

US5179316A · kind A · utility

Assignee

• MCNC · US

Inventor

• Mark D. Kellam · Siler City, US

Key dates

• Filing date: Sep 26, 1991
• Grant date: Jan 12, 1993
• Expiry date: Sep 26, 2011

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10H20/81

Abstract

An electroluminescent display device including a semiconductor substrate having a phosphor layer on one face thereof, and a space charge removing means in the semiconductor substrate. The space charge removing means continuously removes carriers, typically electrons, from the space charge barrier region formed during device operation, to thereby reduce space charge barrier related brightness limitations. The space charge removing means may comprise a doped region in the semiconductor substrate adjacent the phosphor layer, which is DC biased to continuously remove electrons from the space charge region. Alternatively, the doped region in the substrate adjacent the phosphor layer may inject electrons into the phosphor layer, with space charge removal being accomplished by a DC biased substrate contact. The space charge region in the substrate is reduced or eliminated thereby increasing the maximum number of electrons which can be injected into the electroluminescent layer and increasing the brightness of the display device.