Samsung Electronics Co., the world's top memory chip maker, extended its share of the global semiconductor market to more than 10 percent in the second quarter of the year, a U.S. market researcher said Tuesday.

 According to market information provider iSupply, Samsung accounted for 10.1 percent of the global semiconductor market in the April-June period, or US$7.57 billion, to rank second among the world's major chip makers.

It marks the first time that Samsung's global market share has topped the 10 percent mark.

The second-quarter share is up by 5.8 percent from the same period last year, and up 0.3 percent from the previous quarter, the data showed.

The improvement is attributed to its recent active investment in system semiconductors including application processors, according to experts.

System-on-chip, or system semiconductors, refers to integrating all components of a computer or other electronic system onto a single integrated circuit and is a technology frequently used in the latest smartphones and tablet PCs.

 In the global market share list, Intel Corp. ranked first with a share of 16 percent and sales of $12 billion, the data showed.

Texas Instruments Inc. came in third with a market share of 4.2 percent with $3.1 billion in sales, followed by 3.8 percent for Qualcomm Inc. and 3.2 percent for Japan's Toshiba Corp.

Meanwhile, the South Korean tech giant announced its plan earlier in the day to invest $4 billion to upgrade its production line in Austin, Texas to better cater to growing demand for mobile devices.

 Under the plan, the U.S. plant will exclusively churn out system semiconductors, with the switched lines set to start mass production in the second half of 2013, according to the company.